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October 29, 2020

The End Product Of Mastodon Ivroy

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Late Pleistocene societies throughout the northern hemisphere used mammoth and mastodon ivory not only for art and adornment, but also for tools, in particular projectile points. A comparative analysis of the mechanical properties of tusk dentine from woolly mammoth (Mammuthus primigenius) and African elephant (Loxodonta africana) reveals similar longitudinal stiffness values that are comparable to those of cervid antler compacta. The longitudinal bending strength and work of fracture of proboscidean ivory are very high owing to its substantial collagen content and specific microstructure. In permafrost, these properties can be fully retained for thousands of years. Owing to the unique combination of stiffness, toughness and size, ivory was obviously the most suitable osseous raw material for massive projectile points used in big game hunting.

Introduction

Organic projectile technology for big game hunting is considered a crucial prerequisite for the human colonization of the northern hemisphere during the Pleistocene^1,2,3,4,5.

In connection with the appearance of anatomically modern humans, there is an emphasis on the use of hard osseous tissues like cervid antler, large mammal bone and proboscidean ivory for the production of spear and lance heads⁶. Antlers from reindeer (Rangifer tarandus) and red deer (Cervus elaphus), which were easily accessible, easy to work and very tough^7,8,9, were clearly the dominant raw material, especially during the Late Upper Palaeolithic in Europe^{8,10,11,12,13,14,15}. However, ivory from woolly mammoth (Mammuthus primigenius) and from North American mastodon (Mammut americanum) also played an important role in various Late Pleistocene archaeological traditions throughout Europe^10,16,17,18, Siberia^19,20 and North America^21,22.

But why was ivory used for projectiles? The procurement of mammoth tusks was associated with considerable effort or even risk^23,24,25, the material is challenging to work with lithic tools^8,26,27, and other suitable raw materials like antler and large mammal bone were always abundant. But even as woolly mammoths became increasingly rare and finally disappeared from Europe towards the end of the Late Glacial period^28,29, their ivory which could be extracted from natural permafrost deposits, continued to be used by the societies of the Late Upper Palaeolithic for projectile points whenever it was available in sufficient size and quality (Fig. 1)^10,11,24,30. Of course, the optical and haptic attractiveness of ivory is unsurpassed: No other biological raw material has such sublime colours and patterns and takes on such a smooth polish⁷. This is why mammoth ivory was preferred in humankind’s oldest portable artworks²³. In a projectile point, however, favourable mechanical properties like hardness and stiffness for efficient energy transfer into the prey as well as toughness for fracture resistance are crucial^7,8,13,31.

The widespread use of proboscidean ivory in prehistoric tools indicates that it was a suitable raw material for mechanical applications^18,23. But while there are numerous studies addressing the mechanical properties of antler and bone from different taxa (see Supplementary Table S2), corresponding information for ivory is very limited in the case of elephant and missing in the case of mammoth. In 1976³¹, the archaeologist Gerd Albrecht carried out a small series of mechanical tests on the material to investigate its usability for projectile points. He found that extant African elephant (Loxodonta africana) dentine, although very hard and stiff, was more fragile than antler and mammal long bone. These results, however, although widespread owing to a lack of recent studies^7,12,18, are not in accordance with several ivory working experiments, which attest to both mammoth and elephant dentine having a considerable fracture toughness^23,32,33. To counter this paradox and to explore how permafrost ivory compares to fresh material, new data on the chemical composition, microstructure and mechanical properties of tusk dentine from woolly mammoth (M. primigenius) and from African elephant (L. africana) (Fig. 2) were collected and subsequently compared with published information on antler and bone.

Woolly mammoths and the biology of tusks

The genus Mammuthus Brookes, 1828 is assigned to the subfamily of modern elephants, Elephantinae Gray, 1821, along with the extant Asian and African elephants of the genera Elephas Linnaeus, 1758 and Loxodonta [Vigors], 1827 respectively. The woolly mammoth, M. primigenius Blumenbach, 1799, originated in NE Asia roughly 400 ka BP^34,35. In Europe corresponding representatives of the mammoth evolutionary line first occurred much later, during the late Marine Isotope Stage (MIS) 7 or at the beginning of MIS 6, 200–160 ka BP^36,37. Via Beringia M. primigenius reached northern North America during the Late Pleistocene³⁸, where un-glaciated areas were occupied already during the Last Interglacial (MIS 5e, c. 123–110 ka)³⁹. The Holarctic maximum distribution of fully developed woolly mammoths occurred during the last glacial period spanning MIS 5d-2, i.e., approximately the interval between 110 and 14 ka. The verifiable area of the Late Pleistocene range of M. primigenius at that time comprised some 33.301.000 square kilometers³⁷.

Modern elephants have a pair of deciduous and permanent tusks which represent second upper incisors. In woolly mammoth, as in all members of the mammoth evolutionary line both sexes grow tusks. New-born calves have 4–7 cm long deciduous tusks, crowned with a thin layer of enamel. During the first year of the animals’ life, non-enameled tusks replace these milk incisors⁴⁰. The rootless permanent mammoth tusks grow throughout life. They are strictly structured by a succession of dentine cones. Each of these several millimetres to some centimetres thick and up to 35 cm long cones represents the growth progress of one single year. The dentine layers are built up in the tusk pulp cavity, i.e., the most proximal dentine cone is the youngest one. The nutrient- and mineral-rich spring and especially summer months lead to a significant increase of dentine and thereby of the tusks’ length and proximal circumference. During the fall, the growth rate is reduced to come to an end towards the end of the winter. A new growth period begins next spring. The resulting winter / spring discontinuity forms a sharp interface between the dentin cones. Oxygen isotope profiles confirm the annual nature of these cycles⁴¹. The growth history of tusks provides important information about the individual life history of mammoths⁴².

Tusks of M. primigenius, especially those of the relatively small Late Pleistocene forms, are mostly larger in relation to the animals’ body size compared to that of extant Asian and African elephants. Corresponding mechanical features of the ivory (see below) enable such an impressive growth. A stable fixation of the heavy mammoth tusks in the skull is achieved by a strong torsion of the former. The appearance of the teeth is determined by size and shape of the alveolar cavities which contain about one third of the tusks. Changes in alveolar morphology during individual growth of the skull are reflected in the resulting torsion patterns of the tusk.

Male tusks are mostly larger than those of same-age females. The growth pattern of the thinner and less curved female teeth slowed down from their first maternity onwards⁴⁰. As male mammoths, similarly to male extant Asian and African elephants, probably segregated themselves from females over long periods of the year, there was little selective pressure for the latter to increase the size of their tusks⁴³. The tusks of old mammoth bulls can reach lengths of up to 3.5 m and more (measured along the largest radius of the curvature), and weights up to 90–100 kg^40,43. Garutt⁴⁴ refers one isolated case of a couple of fossil tusks from the Indigirka River (Yakutia), each weighing some 150 kg. Observations on African elephant populations show that there is no linear correlation between tusk size and individual age; animals of the same age and sex can develop very different tusk dimensions^45,46.

The original purpose for the evolution of elephantine tusks was presumably intra-specific contest. The size of the teeth signalises the individual status within a group⁴⁷. Well-developed tusks achieve dominance during feeding and drinking competition⁴³ and also act as a threat and weapon in inter-specific conflicts. Observations on extant Asian and African elephants prove, that these animals also use their incisors to gather food by pushing trees down, lifting up rootage or by stripping bark⁴³. The leverage put into action on such occasions can lead to breakage or even to complete loss of tusks, as the existence of recent and fossil “Ganesha” elephants, especially in species with less twisted tusks, testifies⁴⁸. Splintering of the tusk tips occurs also when the animals dig to loosen mineral-rich subsoil⁴³. Elephants have a high individual need especially for calcium and sodium. Rough estimations for requirements of Asian elephants assume up to 60 g Ca and up to 100 g Na per day⁴⁹. Such quantities might have been exceeded by M. primigenius owing to the growth of their larger sized tusks.

The curved incisors of mammoths were less suitable as levers than the tusks of forest or savannah elephants. However, not uncommon sharply deepened scratches and/or extended flat wear facets especially at the outer curvature of the tusks (Fig. 3)^45,50 indicate regular and vigorous ground or ice contact of many mammoth tusks. Probably the animals occasionally moved frozen sediment and wind-hardened or refrozen snow, to prepare and facilitate the taking in of available vegetation of herbs and bushes. The heavy teeth were certainly also used to smash up the ice of frozen-over watering places⁵¹. It seems likely that during all these actions the strongest load was applied to the curved under (respectively outer) side of the teeth.

Results

Chemical composition and structure

Demineralization and deproteinization of tusk samples reveal that both woolly mammoth and African elephant dentine contain mineral and organic phases in similar proportions. According to our experiments the mineral phase is 59.3 ± 0.4 mass-{98880d97af0555a3a517c8aae666eeb64e7bd6d49cbbe05617dcb138f6e48200} for mammoth and 59.4 ± 0.8 mass-{98880d97af0555a3a517c8aae666eeb64e7bd6d49cbbe05617dcb138f6e48200} for elephant. The protein content reaches 33.6 ± 0.7 mass-{98880d97af0555a3a517c8aae666eeb64e7bd6d49cbbe05617dcb138f6e48200} and 33.4 ± 0.8 mass-{98880d97af0555a3a517c8aae666eeb64e7bd6d49cbbe05617dcb138f6e48200}, respectively. The missing proportion of approx. 7 mass-{98880d97af0555a3a517c8aae666eeb64e7bd6d49cbbe05617dcb138f6e48200} can be assigned to the water that evaporated during the drying process. XRD results show that the main crystalline component of proboscidean dentine is hydroxyapatite (see Supplementary Figs S4 and S5). Crystalline domain sizes in the c-direction of apatite were calculated from the (002) peak broadening at 26° using equation (1), and are 21.4 ± 0.4 nm for M. primigenius and 23.0 ± 1.4 nm for L. africana. The intensity ratio I(002)/I(211) of 0.8 for transversal sections of both mammoth and elephant specimens indicates a slight c-axis orientation of the apatite crystals along the tusk axis. The ICP-OES results show that the apatite crystals in both kind of tusks are calcium deficient when compared to stoichiometric apatite (Ca₁₀(PO₄)₆(OH)₂: Ca/P = 1.67) and are substituted by magnesium and sodium ions in a considerable amount (Table 1).

Table 1 ICP-OES results.

Full size table

Mechanical properties

Figures 4 and 5 and Table 2 show the results of the 3-point bending tests. Again, woolly mammoth and African elephant exhibit very similar properties. In the longitudinal direction Young’s Modulus of Elasticity, a measure for the stiffness of a material, is 10.1 ± 0.6 GPa for mammoth and 10.7 ± 0.6 GPa for elephant dentine. The bending strengths are 357.3 ± 26.1 MPa and 369.0 ± 21.8 MPa, respectively. The work of fracture, a measure of the damage tolerance and toughness of a material, is 22.3 ± 10.0 kJ/m² for mammoth and 23.8 ± 6.9 kJ/m² for elephant. In the transversal direction, the mechanical properties are significantly reduced and the Young’s modulus and work of fracture are different for mammoth and elephant. The Young’s modulus is 6.2 ± 0.3 GPa and 5.0 ± 0.5 GPa, and the work of fracture is 0.4 ± 0.2 kJ/m² and 1.1 ± 0.5 kJ/m², respectively. The bending strengths are similar and amount to 94.9 ± 10.7 MPa for mammoth and 97.0 ± 6.4 MPa for elephant (Figs 4a,b and 5a,b).

Table 2 Mechanical properties of Mammuthus primigenius and Loxodonta africana tusk dentine.

Full size table

Additionally, the spatial distribution of both bending strength and Young’s modulus was determined for both orientations as shown in Figs 4c,d and 5c,d. For the longitudinal samples both properties appear to form a gradient with a slight decrease towards the central pulp cavity. Because of the smaller sample size, it is more difficult to see a trend in the distribution for the transversal samples, but there also appears to be a gradient, this time with decreasing values from the inside of the tusk to the outside.

Compression tests of longitudinal sections show that the compression moduli of mammoth and elephant are very similar at 4.7 ± 0.3 GPa and 4.4 ± 0.5 GPa, respectively. The results of the Vickers hardness tests indicate a significant difference in the hardness of the two types of tusks. The mean Vickers hardness (H_V0.1) for mammoth dentine is 35.2 ± 1.2 MPa while elephant dentine has a hardness of 41.2 ± 1.0 MPa.

Discussion

Figure 6 and online Supplementary Table S2 show the mechanical properties of selected vertebrate skeletal and dental elements known from the literature. It is striking that the values themselves are very heterogeneous, even within the same species. In the case of reindeer antler compacta with a relatively coherent modulus of elasticity between 5 and 8 GPa, for example, the bending strength varies by over 300{98880d97af0555a3a517c8aae666eeb64e7bd6d49cbbe05617dcb138f6e48200}. Reasons for this can be the moisture content of the tested samples (fresh, soaked or dry), differing experimental set-ups and inherent variations in a biological material. In any case, there is a clear trend: antler is not as stiff as terrestrial mammal and bird bone, but it is harder to break. This is owing to antler’s lower mineralization⁵². The examined proboscidean dentine, both from permafrost and extant, displays longitudinal stiffness values which are quite high at 10 GPa considering its organic content of 34 mass-{98880d97af0555a3a517c8aae666eeb64e7bd6d49cbbe05617dcb138f6e48200}. For example, the compacta of undomesticated barren-ground caribou (R. tarandus groenlandicus) was previously tested to 5 GPa applying exactly the same test protocol (see Supplementary References S3). At the same time, ivory corresponds to the highest values for bending strength and work of fracture of reindeer and red deer (C. elaphus) antler which is known for its great toughness. Soaked dentine from narwhale (Monodon monoceros) tusk has the same stiffness as dry proboscidean dentine, but is only about 1/3 as strong.

The paradoxical combination of high stiffness, strength and toughness in mammoth and elephant dentine can be explained in particular by its hierarchically oriented microstructure in combination with its high organic content, which essentially consists of the protein collagen⁵³. It is well known that biominerals with a hierarchical organization of their nanoscale microstructure have outstanding mechanical properties in terms of strength and toughness^54,55,56. In the event of a damaging impact, a crack propagates at the interface between the inorganic and organic phase where the specific nano-architecture of the biomineral leads to a significant reduction of crack tip energy owing to energy-dissipating processes such as crack deflection, tilting and twisting⁵⁷. Prominent examples of such biominerals are nacre⁵⁸, conch shell⁵⁹, tooth of marine mollusks⁶⁰, and dermal armour⁶¹.

As with other osseous tissues, proboscidean ivory shows a hierarchical organization on the nanoscale resulting from the specific alignment of apatite crystals along collagen fibrils⁶². Beyond that, the tusks display some unique micro-structural features such as concentric cones that occur during specific growth periods (see above) and a Schreger pattern⁶³ formed by a network of microtubuli that perforate the ivory matrix. In contrast to the parallel alignment of the dentine tubuli in mammalian tooth, the microtubuli in proboscidean tusks are aligned sinusoidal⁶⁴. They form a cross-hatched, helical network of intersecting Schreger lines that is visible to the naked eye. The resulting Schreger angles characterize different evolutionary lines of proboscideans, and can thus help to distinguish between recent and fossil ivory⁶⁵: Schreger angles considerably above 90° are reported for African elephant while for woolly mammoth, they are slightly below 90° (Fig. 2b,d)⁶⁶. This specific orientation also explains differences in the orientation of the apatite crystals in long mammalian bones compared to proboscidean tusk. While the I(002)/I(211) ratio of a hydroxyapatite powder sample is 0.5, it amounts up to 3.4 in long bone⁶⁷. This high ratio indicates a preferred growth orientation of the apatite crystals, whose c-axis is aligned parallel to the collagen fibres in the longitudinal direction of the bone. On the other hand, the intensity ratio of proboscidean tusks is only 0.8, indicating that neither the collagen fibrils nor the apatite crystals are preferentially aligned in the tusk axis, but in a more complex manner following the sinusoidal orientation of the microtubuli. This specific orientation of the microtubuli in proboscidean ivory leads to the observed differences of the mechanical properties in longitudinal and transversal direction, since the majority of elongated helical pores are aligned in the radial direction⁶⁴ and thus facilitate crack propagation. Whereas in longitudinal samples, no significant differences between woolly mammoth and African elephant can be found, in transversal samples, a significantly reduced stiffness but higher work of fracture and hardness for African elephant compared to woolly mammoth are revealed. This indicates that differences in the Schreger angles resulting from a different orientation of the microtubuli (Fig. 2) only have a negligible effect on the mechanical properties when force is applied perpendicular to growth direction but quite a significant one when it is applied parallel to it.

The slightly higher values for longitudinal bending strength and modulus of elasticity in the outer areas of the tusks from both mammoth and elephant might reflect the pattern of mechanical stress caused by their natural use during the animal’s life time (see above).

Conclusion

Proboscidean ivory was an excellent raw material for Late Pleistocene osseous projectile points. Concerning bending strength and work of fracture, mammoth and elephant dentine are comparable to the tough compacta of cervid antler. Thus, corresponding ivory specimens shared their high resilience and durability. In terms of stiffness, proboscidean dentine is superior to reindeer antler, but in some cases can be surpassed by red deer antler. Thanks to its structure, however, it allows the production of completely compact workpieces (Fig. 1a), while antler projectiles of similar size must always consist of a substantial proportion of spongy tissue (Fig. 1b)¹³. Since strength and stiffness are functions of density, the solid ivory projectile is therefore more robust and stiffer than its partially porous antler counterpart. Moreover, with their large dimensions, proboscidean tusks are predestinated for the manufacture of very large projectiles, especially in conditions where suitable timber is scarce or absent^25,68. These unique properties suggest that ivory was the best available osseous raw material for making massive spear and lance heads that could be used to hunt reindeer/caribou (R. tarandus), horse (Equus), bison (Bison priscus), brown and cave bear (Ursus arctos, U. spelaeus) and, of course, woolly mammoth^{10,25,69,70,71,72}. After the regional disappearance of mammoths towards the end of the Pleistocene, their ivory could still be transported from other areas or collected from natural deposits and processed into projectile points of striking appearance and lethal efficiency. Permafrost ivory can not only have the same mechanical properties as fresh material, but was also worked more easily owing to its lower hardness, especially with the groove-and-splinter technique that is typical of Late Upper Palaeolithic projectile production⁷³.

Methods

The experiments used tusks from woolly mammoth from permafrost and extant African elephant (Fig. 2). Both were purchased from the professional ivory carver and authorized dealer Jürgen Schott (Erbach, Germany). The elephant samples come from the left tusk of Loxodonta africana (Cites certification number: DE-122/14 + 2,650 kg). The mammoth samples were taken from a well-preserved Siberian tusk of M. primigenius. Both tusk sections represent seven growth cycles.

To determine the differences in chemical composition and microstructure of mammoth and elephant ivory XRD, ICP-OES, SEM, deproteinization and experimental demineralisation were performed. For XRD, CuKα radiation (λ = 1.5406 Å) and measurement time of one hour per sample were used (2 Theta range 15–72°, step size 0,005°, scan rate c. 1°/min). For each kind of tusk, five samples taken from similar relative positions were measured in the tusk growth direction (Fig. 2a,c). The crystal domain size τ in direction of the crystallographic c-axis was calculated using the Scherrer equation (1)

τ = K λ β c o s θ

(1)

with the shape factor K which was assumed as 0.9, the wavelength λ, the FHWM and the Bragg angle θ of the (002) peak at 2θ = 26°. For each tusk, the mean value, standard deviation and variance were determined (Supplementary Table S6).

ICP-OES samples were prepared by dissolving 50 mg ivory powder in 2 ml of concentrated nitric acid (65 mass-{98880d97af0555a3a517c8aae666eeb64e7bd6d49cbbe05617dcb138f6e48200}) for two hours. After dissolving, 8 ml of pure water were added.

For demineralization, samples with a volume of approx. 300 mm³ were stored in 0.6 M hydrochloric acid. The acid solution was replaced every 24 hours. After seven days, the samples were washed with de-ionized water and freeze-dried for another 24 hours. For deproteinization, samples with a volume of approx. 300 mm³ were kept in a 2.17 wt{98880d97af0555a3a517c8aae666eeb64e7bd6d49cbbe05617dcb138f6e48200} sodium hypochlorite solution for 14 days, which was replaced every 24 hours. The samples were then washed with de-ionized water and dried for 24 hours.

Specimens for 3-point bending tests and compression tests had dimensions of 3 mm*4 mm*25 mm and 5 mm*5 mm*10 mm, respectively. The moisture content was 7 mass-{98880d97af0555a3a517c8aae666eeb64e7bd6d49cbbe05617dcb138f6e48200}. Samples were taken in two different orientations, longitudinal (in growth direction of the tusk) and transversal (perpendicular to the growth direction). To ensure exact orientations, the samples were extracted from 30 mm thick slices cut perpendicular to the pulp cavity (Figs 2, 4c,d and 5c,d).

For 3-point bending tests, 30 longitudinal and 12 transversal samples were used. The samples were cut with a carbide saw blade from the dentine part of the tusks. The samples were then polished before the mechanical test using 1200 grit coated abrasives. Both sawing and polishing were carried out at low speed to avoid dehydration and collagen degradation. The tests were conducted at room temperature on a Zwick/Roell Z020 machine. The distance between the sample carriers was 16 mm. The pre-load was 0.5 N and loading speed 2 mm/min. The breaking point was determined by the total failure of the samples defined by a 20{98880d97af0555a3a517c8aae666eeb64e7bd6d49cbbe05617dcb138f6e48200} decrease in the test load.

To determine the hardness of the ivory, Vickers hardness tests were conducted on polished samples parallel to growth direction with a Vickers pyramid and a Shimadzu HMV-2000 machine. The load was 100 g and load duration was 10 seconds. Twenty measurements were carried out in each case.

Data Availability

All data generated or analysed during this study are included in this published article (and its online Supplementary Information files). The samples on which the 3-point bending tests and compression tests were carried out are archived at the Senckenberg Research Station of Quaternary Palaeontology in Weimar, Germany. Mammuthus primigenius: IQW 2018/45 415 (Sibirien 50 724), IQW 2018/45 416 (Sibirien 50 725), IQW 2018/45 417 (Sibirien 50 726). Loxodonta africana: IQW 2018/45 418 (Afrika 50 727), IQW 2018/45 419 (Afrika 50 728), IQW 2018/45 420 (Afrika 50 729).

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Acknowledgements

The authors thank doc. Dr. Zdeňka Nerudová and doc. Dr. Petr Neruda for granting access to the osseous projectile points from Pekárna cave in the Moravské Zemské Muzeum collections (Brno, Czech Republic). We also thank Fedor Shidlovskiy and Dr. Irina Kirillova for the photographs of the mammoth tusk in the National Alliance of Shidlovskiy “Ice Age” collection (Moscow, Russia). The research was funded by the Deutsche Forschungsgemeinschaft (Grant number PF 841/2-1).

October 29, 2020

Distinction Between Elephant and MastodonIvroy

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Distinguishing elephant from ancient ivory is challenging and becoming more and more important for the owners of knives with handles of ancient ivory. However, there are two reliable keys to make the determination easier.

Polished cross sections of elephant and mastodon/mammoth ivories display stacked chevrons of cross-hatched lines called Schreger lines or Lines of Retzius—incremental lines of rhythmic deposition of successive layers of enamel/dentine matrix during development. The Schreger lines closest to the outer bark of the tusks are the most visible—and the ones to measure—though there are also inner Schreger lines that are less discernible around the nerve cavity. The intersection of Schreger lines form angles, and this is the key—if the average angle is greater than 115 degrees, then it’s elephant ivory; if the average angle is less than 90 degrees, it’s mastodon or mammoth. Variations in the angles can occur in individual tusks, particularly as the patterns tighten more toward the center. Plus, the visible cross section must be cut square to the axis of the tusk—otherwise the chevrons’ angles will be distorted.

Specimens from both extinct and existing animals can show angles between 90 and 115 degrees in the outer Schreger lines, so the differentiation should never be based solely on a single angle measurement when the angles fall in this range. When averages are used, a clear separation between the ivory of existing elephants and extinct mammoths/mastodons exists. Elephant ivory averages above 100 degrees and mammoth/mastodon ivory averages below 100 degrees.

Another I.D. key, though more involved, can also distinguish mammoth or mastodon ivory from elephant. These ancient ivories can often have blue-green or brownish blemishes on the surface produced by an oxidized iron phosphate called vivianite. Even if the discoloration is barely visible, ultra-violet light will make it stand out with a dramatic velvety-purple appearance. Even if elephant ivory were similarly discolored—though in its natural state, elephant ivory will not display the same discoloration—it would not exhibit the characteristic fluoresence of vivianite.

October 29, 2020

About Mastodon Tusks

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Until recently, I did not fully appreciate fossil teeth. Their significance for identifying species and narrowing down the general diet of extinct animals was obvious, but I didn’t understand that teeth also hold intricate records of an individual animal’s life. Tiny pits and scratches on enamel can reveal what a creature was eating around the time it died; oxygen isotopes preserved inside teeth can be used to make inferences about climate, body temperature, and habitat; and the way teeth respond to stress and strain can allow paleontologists to identify the feeding habits of long-dead species.

Prehistoric teeth can also be confusing. Like modern elephants, American mastodon had large tusks that were actually modified upper incisor teeth. The tusks of these recently-extinct behemoths – known as Mammut americanum to paleontologists – are ivory records of their lives, but isolated tusks have presented scientists with a persistent problem.

American mastodon tusks were obviously quite different from the incisors in our own mouths. For one thing, they kept growing throughout the life of the individual animal, changing shape and size as they did so. Tusks of Mammut were also sexually dimorphic, meaning that the tusks in the adult animals were significantly and consistently different in males and females. Two sexes, two adult forms.

The trouble is that the tusks of young male mastodons look like those of adult females. Even though there were only two adult tusk forms, the tusks of juvenile males passed through a stage in which they looked like tusks from mature females. This has frustrated attempts to determine what an isolated tusk means for the life history of an individual animal. In order to correctly identify the sex of an animal from a tusk, you also have to know its age, without which the details of the animal’s life history are confounded.

In previous studies, for example, University of Michigan paleontologist Dan Fisher has found that signs of pregnancy in female mastodons can be detected by studying the details of the dentin that makes up the majority of their tusks. So too can details of musth – a spike in testosterone associated with mating and aggressive behavior – be seen in the tusks of male mastodons. But these patterns can only be properly interpreted when the sex of the animal the tusk belonged to is known. If the tusk of a young male is confused for that of an older female, the evidence embedded within the tusk will be misinterpreted. In turn, confused findings about misattributed tusks can affect hypotheses about why the American mastodon disappeared, as Fisher has used deep-tusk records from North American proboscideans to argue that they show similar birth intervals to elephants under hunting pressure and were therefore being turned into mammoth steaks by prehistoric humans.

Paleontologist Kathlyn Smith recently worked with Fisher to find a way around the problem of ambiguous mastodon tusks, and a detailed account of their attempt has just been published in Paleobiology. What they were looking for was some kind of distinguishable pattern in tusks of both male and female mastodons that could be used to separate the sexes without any other information from the rest of the skeleton. Twenty one mastodon tusks collected in the Great Lakes region of the United States were investigated in the effort to detect these trends.

The twenty one tusks used in the study already had male or female sex assignments based upon skeletal evidence, dental evidence, or the correlation between tusk circumference and the depth of the pulp cavity. Rather than accept these at face value, however, Smith and Fisher wanted to see if these assignments held true by looking at the details of the tusks themselves using principal components analysis. The purpose of this technique was to cut through variation within the sample to see if certain aspects of the tusks were truly related to one another. The data included the circumference of the tusk at several points, in addition to the depth of the pulp cavity and other features. Since the tip of the tusk was the oldest, and the tusk portion closest to the skull was the youngest, measurements from different portions of the tooth could be used as indicators of tusk anatomy at different points in the a

Smith and Fisher found that the depth of the pulp cavity could be a useful indicator for investigating the sex of some mastodons. Even though tusks grew longer and added to their circumference throughout life, the pulp cavity inside the tusk only changed at a few key times – the pulp cavity grew deeper in young animals, stayed at that depth for some time, and then became shallower in old adults. A tusk with a large circumference relative to the depth of the pulp cavity, for example, came from an older mastodon, while a tusk with a larger pulp cavity compared to tusk circumference represents a young individual. This means that pulp cavity depth can be used as a rough estimate for age, and, compared to the length and circumference of the tusks, may help distinguish between tusks belonging to males or females. Still, this variable would mainly distinguish between the tusks of adults and would not have enough resolution to tell the difference between a young male and an adult female.

Measurements from the circumference of the tusk at various points provided a more refined look at age. Paired with pulp cavity depth, the measurements of tusk circumference allowed the approximate ages of the mastodons to be plotted. These were in accord with what had previously been suggested on the basis of other bones from the same animals. This means that paleontologists can estimate age of a mastodon on the basis of tusk anatomy alone and, in turn, these findings can be used to more accurately determine if a relatively short and thin tusk comes from a young male or an adult female.

Paleontologists can’t simply take the measurements and throw them into the computer, though. Detailed knowledge of each tusk is needed to weed out factors that could trip up age assignments. Smith and Fisher mention a pair of tusks from two different female mastodons informally called North Java and Powers. Both tusks came from females of similar age and generally corresponded in overall shape, but the North Java mastodon had worn down about 50 centimeters from the tip of her tusk, obliterating about six years worth of growth. This would make the North Java female seem younger than she actually was in the analysis, and so Smith and Fisher had to correct for the damage the tusk suffered in order to accurately approximate the animal’s age.

Despite such potential confounding factors, though, the results obtained by Smith and Fisher were consistent with the sex assignments that had been proposed on the basis of other teeth and bones found with many of the mastodon specimens in the study. When analyzed carefully, tusks alone can be used to distinguish between males and females across a range of ages. This might prove to be very useful for paleontologists studying the last days of the mastodons and mammoths. If paleontologists are studying a bonebed with several isolated or disassociated tusks, Smith and Fisher suggest, the scientists can still identify the ages and sexes of the animals those teeth belonged to and determine whether the assemblage is consistent with a herd or instead represents a group of bodies that accumulated in one place over a long period of time. The same techniques may also allow paleontologists to distinguish between male and female mammoths belonging to dwarfed island populations, as well, in which the change in size masks the differences between the sexes. Mammoths and mastodons have been extinct for thousands of years, but they have left us wonderful records of their Pleistocene lives inside their tusks.

October 29, 2020

Are Woolly Mammoths Still In Existence??

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As a substitute for coveted elephant ivory, mammoth tusks can sell for hundreds of thousands of dollars. A rush is underway to dig them out of the frozen earth in Siberia and sell them, mostly to China. The hunt is making millionaires of some men living in this impoverished region — but it’s also illegal.

Photographer Amos Chapple followed a group of tusk hunters in Siberia on assignment for Radio Free Europe/Radio Liberty. He recalled his three-week journey with NPR’s Ailsa Chang.

This interview has been edited for length and clarity.

Interview Highlights

On seeing his first tusk

I saw just one beautiful example of a tusk that came out of the ground right in front of me — it was still, like, cold to the touch when it came out. It weighed about [135 pounds] and it was curled. You know, mammoth tusks are very distinctive, because they’re very curly. … They corkscrew a little bit. And you can still smell the animal in them as well.

World

As Arctic Ice Melts, It’s A Free-For-All For Oil … And Tusks

On how these tusks are excavated

The reason that Siberia is such a mecca for mammoth tusk hunting is because of the permafrost. So there were mammoths everywhere, and they died and their bones sank into the earth, but in most places they rotted because the soil is warm. But once they lock into the permafrost they can just be there almost indefinitely — the bones just don’t decay inside that permafrost.

So you need to carve away that permafrost. And the method that they’ve developed is to get firefighting pumps, and they pull water out of a nearby river, and then they blast away. …

Once they see the end of a tusk, they’ll just give it a little wiggle, and then blast it some more, give it another wiggle, and eventually it’ll come out. It’s like extracting a tooth.

Tusk hunting causes erosion along the edges of the hill.

Amos Chapple/RFE/RL

On what the excavation does to the environment

They would pull water out from the rivers, they’d blast it into the hillside, and those hillsides would effectively melt back into the river. And so the rivers were completely full of silt. It should be one of the most pristine places on Earth, and these guys didn’t even bother taking fishing rods, because the fish were gone.

The Two-Way

Good News For Elephants: China’s Price Of Ivory Has Plummeted

On the “pretty miserable” hunting conditions

The mosquitoes: that was what made life really, really horrible. … I remember one day I was trying to cross one of these streams when I fell in, and I sat on the bank and I took off one of my gumboots and tried to squeegee out my sock. And the moment I did that, all these black mosquitoes descended on my white, white feet and the contrast was just so superb. …

I took a couple of pictures and then I put my socks back on, and then I limped and whimpered my way towards the river — and I remember thinking I would pay hundreds of dollars right now to be able to plunge my feet into icy, cold water.

October 29, 2020

Everything to Know About Woolly Mammoth Tusk

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During the Ice Age, woolly mammoths roamed across vast territories, covering Europe, northern Asia and North America. Two pieces of tusk in our collection show that some woolly mammoths made their home in Scotland, while another provides early evidence of mammoths in North America. And can you help us solve the mystery of the disappearing tusk?

Wolly Mammoth tusks in our collections

This piece of tusk shown below was found on 1 July 1820 by workmen digging the Union Canal on the Cliftonhall Estate to the west of Edinburgh. Originally it weighed almost 12 kg and was almost a metre long. Against the wishes of the estate owner, Sir Alexander Maitland Gibson, the workmen sold it in Edinburgh for £2 for carving. By the time Gibson had discovered what had happened, the tusk had been cut into three pieces, two of which were recovered. It was donated to the Free Church College by 1822.

In 1966 the Free Church College Museum was closed and many important specimens came to National Museums Scotland. However, the mammoth tusk had disappeared. It was discovered in 1998 by Hilary Kirkland of the City of Edinburgh Education Department and donated to National Museums Scotland. The tusk had been cut in half, but we don’t know where the missing piece is. If anybody knows, please can you contact Dr Andrew Kitchener, 0131 247 4240, a.kitchener@nms.ac.uk

We took a sample form the tusk and had it radiocarbon dated. This revealed that this woolly mammoth died on what is now Cliftonhall Estate about 29,000 years ago.

Woolly mammoth tusk from Cliftonhall, West Lothian.

In Ayrshire

The piece of tusk below was discovered in January 1817 by Robert Brown at Greenhill Quarry, Kilmaurs, Ayrshire under 17 and a half feet (5.25 metres) of clay. It was cut in two by the Earl of Eglinton; one part was kept at Eglinton Castle and the other half was donated to the College Museum of the University of Edinburgh. In 1915 the Eglinton Castle piece shown here was donated in 1915 by the Earl of Eglinton to the Royal Scottish Museum, the forerunner of National Museums Scotland. Several other pieces of mammoth tusk were discovered in quarries at Kilmaurs during the early 19th century. Radiocarbon dating has revealed that the tusk is around 27,000 years old.

Woolly mammoth tusk from Greenhill Quarry, Kilmaurs, Ayrshire.

HMS Blossom in Alaska

The two large woolly mammoth tusks pictured below were discovered by Captain Frederick William Beechey, who led a polar expedition from 1825 to 1828 on HMS Blossom to explore the Bering Strait between Asia and North America. The tusks were found in September 1826 in a cliff of frozen mud at Elephant Point in Eschscholtz Bay, Alaska. They are among the first remains of woolly mammoth recorded from North America. One of the tusks was recently radiocarbon dated and found to be 46,600 years old.

October 29, 2020

Mammoth Tusk Can Talk,Is it True??

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One day, about 11,000 years ago, a lone bull mastodon plodded through the shallows of a lake in what today is Michigan. Some time later, three females and a gamboling calf passed the same way. Luckily for paleontologists, clay-rich mud filled the animals’ footprints, preserving the tracks and giving scientists insights into the mastodons’ social structure. The long-extinct creatures likely lived in matriarchal herds, while mature males roamed singly, much like their modern-day relatives: elephants.

Today, elephant numbers have dwindled, as has their range. They’re now considered vulnerable in Africa and endangered in Asia. But during the Pleistocene epoch, between 2.6 million and 11,700 years ago, elephants and their diverse relatives stomped across an impressive swath of the globe, from the Arctic to South America. Even back then, elephants were the most plentiful, diverse and widely distributed of this group, the Proboscidea. It also included mammoths, mastodons, and less well-known members such as stegodons and gomphotheres. Their trunks and tusks make them all recognizable cousins.

Thanks to fossils, preserved tracks, recent finds of proboscideans frozen in permafrost, and new technologies used to probe these ancient lineages, researchers are learning more about the lives and deaths of proboscideans, says Daniel Fisher, a paleontologist at the University of Michigan in Ann Arbor.

Dick Mol and colleagues’ find of the bones of the Yukagir Mammoth in Siberia inspired the creation of this replica of the extinct animal, tusks, hair and all. (Credit: Remie Bakker, Manimal Works, Rotterdam)

Fisher studies fossil tusks because they grew throughout the animal’s life, preserving a record of nutrient intake and habits. “They essentially carry diaries of their lives around with them,” says Fisher. His team finely analyzes the layers of dentin in fossilized tusks. These layers provide data on individual months, or even weeks or days, in a proboscidean’s lifetime.

Fisher expects his analyses will answer the ultimate question: What happened to these creatures? At the end of the Pleistocene, most proboscideans, along with many other large mammals, disappeared from the Earth. It wasn’t a sudden event, notes Dimila Mothé, a postdoctoral fellow in the mammalogy lab at the Federal University of the State of Rio de Janeiro; new fossil finds show that species in some parts of the world held on for several thousand years, or in some cases tens of thousands of years, longer. Still, by modern times, the once-diverse proboscideans — which numbered a dozen or so during the Pleistocene — had dwindled down to just two or three species, depending on how you count.

Two main explanations for the massive creatures’ departure have long been debated. One is that changes to the climate resulted in an environment — warmer, perhaps drier, or with more seasonal changes — that most proboscideans could not tolerate. The other is that humans hunted the animals to extinction.

It’s a question with resonance for the future as well as the past. The current decline in elephant numbers may not be a new extinction event, but simply the tail end of the ongoing extinction of all proboscideans, suggests Mothé. Understanding the plight of the Pleistocene proboscideans could help scientists predict or avert the fate of their modern descendants.

Here are some of the latest insights into daily lives and eventual disappearance of the prehistoric proboscidean:

1. Mammoth Diets Included Some, Well, Interesting Things

In 2007, reindeer herders in Siberia discovered the frozen carcass of a female mammoth calf. Named Lyuba, for the wife of the herder who reported the find, the calf had suffocated in a pool of mud about 40,000 years ago. The mud preserved not only her body, but the contents of her gut, too.

She had consumed milk, no surprise for a one-month-old calf (her age was apparent from the layers of dentin in her teeth.) Her stomach also contained chewed-up plant remains — yet she wasn’t mature enough to have done the chewing herself.

And there was something else in the intestine: fungi that typically grow in poop. For Fisher and the other paleontologists, the conclusion was clear: Lyuba had noshed on mammoth feces that included both fungi and undigested plant matter.

Discovered in 2007 in Russia’s Arctic Yamal Peninsula, Lyuba died roughly 40,000 years ago, only a month old. Her skin and organs were well preserved, and studies of the contents of her stomach and intestine have led to new understandings of mammoth diets. (Credit: Matt Howry/Wikimedia Commons)

Modern elephants do this too. Babies obtain the microbes they need for digestion from Mom’s waste. Adults also eat feces, a practice scientists call coprophagy. Because of the way their digestive systems are set up, coprophagy helps the animals extract additional nutrients from their food.

The scientists found other oddities in Lyuba’s digestive tract: mammal hair and a vole bone. What were those items doing in the gut of an herbivore? Perhaps, as the springtime weather melted snow and revealed the vole’s stored hay, the hungry mammoth mother gobbled up the animal along with the hay by accident, Fisher speculates. But eating rodents could also have been a way for mammoths to gain extra nutrients at the end of the winter.

2. Woolly Mammoths Roamed a Land That Was Cold but Not So Snowy.

Of course, the main dish for a proboscidean was vegetables, and the kinds of plants they ate can tell scientists something about where the animals lived. Clues can be found in the carbon in the animals’ fossilized tusks and teeth. Different kinds of plants contain different ratios of carbon isotopes, which are reflected in tooth fossils and allow scientists like Fisher to glean information on diets. From those same ratios, he can even infer when the animals were living off their own fat stores during wintertime.

Another piece of evidence comes from tooth wear. Grasses contain mineral particles called phytoliths, which leave scratches on the teeth. Bushes and trees, containing fewer phytoliths, create a different pattern. The scratches in fossilized teeth reflect the diet of a creature in its final weeks or days.

“We call it the ‘last supper’ effect,” says Gina Semprebon, a paleoecologist at Bay Path University in Longmeadow, Massachusetts.

Ancient mammoths and mastodons incorporated records of their entire lives in their teeth and tusks. In a tooth, layers of dentin are laid down over the animal’s lifetime. Carbon isotope ratios in the dentin layers can tell researchers about the kinds of plants and amounts eaten. Scratch patterns on the enamel also yield information about what the animals ate.

“What really impresses me about the proboscideans is the flexibility in their diet,” she adds. They could eat grasses or shrubs at different locales and times in their lives; at least one lineage switched its preference as it evolved. Or two species in the same area could split the options, with one focusing on bushes and one on grasslands. “That’s how you survive, long-term, in evolution,” says Semprebon.

The findings can get more specific than just grasses versus shrubs, though. Dick Mol, a mammoth researcher at the Rotterdam Museum of Natural History in the Netherlands, once obtained the frozen intestine of what is called the Yukagir mammoth, discovered in Siberia’s Yakutia region in 2002. He took it back to the Netherlands, thawed it, and to his surprise, found it was full of undigested food and dung.

Mol immediately phoned Bas van Geel, a paleoecologist at the University of Amsterdam. Van Geel arrived at Mol’s home half an hour later; subsequently, he analyzed the gut contents by microscopy, chemistry and DNA sequencing.

The researchers found dung-inhabiting fungi, supporting the coprophagy theory. They also found plant remains and pollen from grasses and sedges, as well as herbs, mosses and dwarf willow twigs. The plants were of types adapted to frigid, dry conditions and open spaces — an environment that researchers envision as the “mammoth steppe.”

“The woolly mammoth was living on a cold and dry, almost treeless, mammoth steppe environment,” says Mol. With little snow, the mammoths would have been able to dine on freeze-dried plants throughout the winter, suggests van Geel.

University of Michigan’s Dan Fisher and his team oversaw the excavation of a mammoth skull and tusks found on a soybean farm near Chelsea, Michigan in 2015. Nicknamed the Bristle mammoth, after farmer James Bristle, the fossils were from an adult male that died more than 10,000 years ago. (Credit: Daryl Marshke/Univ. of Michigan Photography)

University of Michigan’s Dan Fisher and his team oversaw the excavation of a mammoth skull and tusks found on a soybean farm near Chelsea, Michigan in 2015. Nicknamed the Bristle mammoth, after farmer James Bristle, the fossils were from an adult male that died more than 10,000 years ago. (Credit: Daryl Marshke/Univ. of Michigan Photography)

3. Woolly Mammoths had Cold in Their DNA.

Elephants live in warm climes such as desert or savannah. How did their ancient relatives, the woolly mammoths, survive that chilly steppe? In 2015, scientists reported the genome sequences of three Asian elephants and two woolly mammoths. Comparing the DNA of the ancient and modern creatures, a team led by Stephan Schuster, a genomicist at Nanyang Technological University in Singapore, identified differences in hundreds of genes.

These genetic differences, Schuster and his colleagues reason, gave mammoths adaptations like thick fur and smaller ears, the better to conserve body warmth. Other distinctive mammoth genes likely played a role in the animals’ fat storage, temperature sensitivity, blood sugar regulation and weight. The scientists think that these adaptations would also have helped the animals thrive in cold. Even genes associated with circadian rhythms differed, which might reflect an adaptation to cope with the midnight sun of arctic summers and the dark days of northern winters.

A woolly mammoth trunk found in Siberia in 2010 also suggests adaptation to the cold. The trunk skin contains a hoodlike expansion, which might have served as a sort of “fur mitten” that the mammoth could tuck its frost-nipped trunk tip into.

4. You Do Not Want to Mess With the Musth

Modern-day male elephants, about once a year, enter a phase called “musth” when their thoughts turn to mating and their testosterone levels skyrocket to as much as 60 times normal. For weeks or even months, they become aggressive, and testosterone-rich liquid dribbles from glands next to their eyes.

Did Pleistocene proboscideans do the same? While paleontologists can’t be sure, the evidence indicates that they did. Using CT scans and other techniques to examine the dentin layers from tusks, Fisher has shown that mature male proboscideans regularly fasted, as modern elephants do during musth.

By slicing and finely analyzing fossil tusks, researchers can learn what ancient mammoths, mastodons and other proboscideans ate or where they lived during each year of their lives. Finer layers can allow scientists to parse weeks or even days at a time.

Researchers have also observed evidence of a gland like the one in modern elephants in several frozen specimens from Siberia. And some fossils have preserved evidence of the male-on-male violence that typically happens during musth. For example, the Crawford mammoths found in Nebraska are two adult males who locked their tusks around each other’s heads and died, likely of dehydration and starvation, while still hooked together.

The likelihood of musth is another piece of evidence, along with the Michigan footprints, suggesting that early proboscideans maintained a social structure similar to elephants today, with matriarchal herds and solitary adult males.

Fisher sees records of female reproductive status in tusks, too. This, presumably, reflects the slower or faster growth rate of the tusk in times of poor or rich food supply. But in adult females, Fisher sees a regular, multiyear pattern. The thickness of annual layers drops for about 2.5 years, then rises for 1.5, making a four-year cycle. He thinks this reflects a nearly two-year pregnancy, similar to the gestation period of modern elephants, when calcium and phosphorus are diverted from teeth and tusks to the growing fetus. That, he suspects, would be followed by the time the mother spent nursing her calf, which could also divert minerals from teeth and tusks.

5. New Evidence From Mammoth and Mastodon Fossils Hints at Humans as Prime Suspects in the Animals’ Disappearance. But the Jury is Still Out

In those calving cycles and other tusk patterns, Fisher seeks the explanation for the extinction of most mastodons, mammoths and their relatives. Based on his new analyses of dentin layers and radioactive isotopes in tusks, never done before at so fine a resolution, he’s concluded that human hunters are to blame. Here’s his reasoning, with respect to calving rates:

If climate change made it hard for mammoths to find food and survive, then they would have had fewer calves, with longer intervals between births. Studies of their tusks should reflect nutritional deficiencies.

But what Fisher sees in the tusks is mammoths enjoying solid nutrition, fast growth and regular, frequent reproduction, particularly as the Pleistocene drew to a close. That’s the pattern he’d predict if hunters were picking off herd members, because there would have been more food around for those still living.

In Dan Fisher’s lab, a fossilized tusk is painstakingly put together from hundreds of fragments. (Credit: Daryl Marshke/Univ. of Michigan Photography)

In Dan Fisher’s lab, a fossilized tusk is painstakingly put together from hundreds of fragments. (Credit: Daryl Marshke/Univ. of Michigan Photography)

“It doesn’t matter whether you look at growth rates, you look at age of maturation, first calving or calving intervals, they all change in the direction predicted by the hunting hypothesis,” says Fisher. However, he cautions that he’s looked at only several dozen tusks so far, and he would like to have ten times as many data points to build his case.

Most other scientists think climate change played a more important role. “The demise of the mammoth steppe was dramatic,” says Mol. Analysis of pollen in lake sediments reflects a major climate change about 13,000 years ago, with the dry steppe and grasslands turning to wet tundra and forests, says van Geel. Plus, he adds, the wet winters would have meant more snow, and the animals might have struggled to find food under accumulated drifts.

Schuster also supports the idea that climate was the major factor. It would have been hard for large proboscideans to move on the soggy ground, he says. Plus, his DNA analyses indicate that one group of mammoths died out before people ever entered its range. “We are totally off the hook for that extinction,” he says.

Schuster also thinks that going after an animal as large as a mammoth would be a risky proposition for a band of early humans. Mol, too, doesn’t dispute that people may have killed mammoths, but doubts we killed them all.

Of course, the answer needn’t be black or white. Both Mol and Van Geel suspect that multiple factors were at play, including not only climate and hunting, but also illness, inbreeding and isolation as populations dwindled.

Certainly, it’s likely that more than one factor doomed the Pleistocene proboscideans, agrees Fisher, but he still argues that the hunting was a stronger factor than climate change.

What does that mean for the elephants — the only remaining proboscideans?

Poaching and Habitat Loss: Clear Threats to Elephants

According to the organizers of World Elephant Day, elephant populations have dropped by 62 percent in the last ten years. There are about 400,000 African elephants left, and fewer than 40,000 Asian elephants. In this case, it’s clear what is killing the elephants: poaching driven by humankind’s desire for ivory. Habitat loss due to human activity is also a factor.

But this time, humans are paying attention. Thanks to the Convention on International Trade in Endangered Species of Wild Fauna and Flora, ivory trade has been banned officially since 1990. Elephant lovers are using trackers and other technology to find elephants and protect them from poachers. Bay Path’s Semprebon, for one, hopes that as people become aware of the remarkable history of proboscideans, they’ll be more eager to save the last ones.

October 29, 2020

Why we need to protect the extinct woolly mammoth

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An audacious world-first proposal to protect an extinct species was debated on the global stage last week.

The plan to regulate the trade of woolly mammoth ivory was proposed, but ultimately withdrawn from an international conference on the trade of endangered species.

Instead, delegates agreed to consider the question again in three years, after a study of the effect of the mammoth ivory trade on global ivory markets.

Why protect an extinct species?

The Convention on the International Trade in Endangered Species of Wild Fauna and Flora (CITES) is an international agreement regulating trade in endangered wildlife, signed by 183 countries. Every three years the signatories meet to discuss levels of protection for trade in various animals and their body parts.

The most audacious proposal at this year’s conference, which concluded yesterday in Geneva, was Israel’s suggestion to list the Woolly mammoth (Mammuthus primigenius) as a protected species.

Specifically, it aimed to list the woolly mammoth in accordance with the Convention’s “lookalike” provision. Once woolly mammoth ivory is carved into small pieces, it is indistinguishable from elephant ivory without a microscope. The proposal is designed to protect living elephants, by preventing “laundering” or mislabelling of illegal elephant ivory.

Once carved into small pieces, elephant and mammoth ivory are indistinguishable without a microscope. Thomas Quine/Flickr, CC BY

Had it passed, it would have been the first time an extinct species has been listed to save its modern-day cousins. Most populations of woolly mammoths went extinct after the last ice age, 10,000-40,000 years ago.

Wait, you can trade mammoth ivory?

The trade in woolly mammoth tusks lies at the convergence of Earth’s environmental crises.

As the climate crisis melts permafrost in the Siberian tundra, preserved mammoths bearing tusks as large as 4.2m long (weighing as much as 84kg) have been unearthed for the first time in millennia.

International trade in mammoth ivory is not illegal (except for import to India under domestic legislation), and the domestic trade of Woolly mammoth ivory is not banned by most countries.

While poorly documented, the main trade route for tusks is thought to be from Russia to Hong Kong and then mainland China for processing.

Imports to Hong Kong have increased dramatically from fewer than 9 tonnes per year from 2000 to 2003 to an average of 31 tonnes per year from 2007 to 2013. Similarly, one survey found a fourfold increase in mammoth ivory sales in Macau between 2004 and 2015.

It’s not all mammoth

While some of this mammoth trade is legitimate, plenty of traders are passing elephant ivory off as mammoth. Research has found that, while it’s very hard to tell how much of the legal mammoth trade is actually (illegal) elephant ivory, tighter regulation may reduce opportunities for the laundering of elephant ivory.

The proposal would not ban trade altogether, but would require an exporting country to prove that specimens are mammoth ivory to get a permit.

Ivory laundering goes the other way as well. Grade A mammoth ivory can be carved and passed off as elephant ivory trinkets and enter the illegal wildlife trade.

The illegal wildlife trade claims the lives of 20,000-50,000 elephants annually and is the second greatest direct threat to species survival.

Selling elephant ivory is largely illegal around the world, but the mammoth trade creates a huge loophole. Paul Williams/Flickr, CC BY-SA

Is it woolly thinking?

The new proposal was not without its detractors. Some “ice ivory” sellers and carvers argue mammoth ivory should be promoted as an alternative to elephant ivory to meet market demand without poaching. Others maintain extinct species should be regulated by the laws and codes observed by the global antiquities trade.

While Israel has not taken positions on these points, the move would be in line with other global efforts to stem the tide of organised crime syndicates profiting from the illegal wildlife trade.

My own research, along with government inquiries around the world, has found legal markets in ivory, regardless of origin, can and will be exploited as conduits for illegal trade.

Further, a recent analysis of the global online antiquities market found dealers and buyers have resoundingly poor legal literacy. Ethical dealer behaviour is highly inconsistent.

A solution put on ice

If it had passed, this proposal would have been a landmark achievement in the protection of elephants. Instead, Israel’s delegates ultimately withdrew the motion, in the face of vehement opposition from Russia, which is the primary exporter of mammoth ivory.

Delegates from Canada, the United States of America and the European Union said there was insufficient evidence to support the change. The various parties agreed to support a study into the mammoth ivory trade as a compromise, and Israeli delegates are hopeful the findings will reopen discussion at the next conference, three years from now.

October 29, 2020

Causes of Woolly Mammoth Disappearance

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lancing into the 50-metre-deep hole the two tusk hunters smiled. Together, they heaved out a caramel-coloured mammoth tusk from the soil where it had been frozen for at least 10,000 years. Their dog, too, seemed to be interested in the find. “Because it’s been locked in the ice for that long it still smelled of the meat, it still smelled of the animal,” says Amos Chapple, who spent three weeks photographing mammoth tusk hunters at work in the Siberian region of Yakutia.

The tusk hunters cleaned their find with dry grass and quickly wrapped it in cling film to keep it moist and preserve valuable weight that would push up its price when it came to selling it. Then the precious cargo, along with two other tusks, went on a winding five hour speedboat journey down a river in northeastern Siberia. The 65kg relic was later sold for $34,000 (£26,800) to a Chinese dealer waiting in the tusk hunters’ village, earning them a total of around $100,000 (£77,000) in just eight days. Everything they left behind – mammoth skulls and bones – was consumed by the elements.

The frozen land of Siberia is rapidly thawing. Parts of it are warming twice as fast as the rest of the planet. The permafrost – soil that remains frozen year-round – is protected by a surface layer of dirt and sediment that thaws in summer and refreezes in winter. But in 2018, some parts of this layer did not freeze at all, leaving the permafrost exposed to even warmer temperatures than usual. For decades, residents of this frozen land, where temperatures regularly dip below minus 30 degrees Celsius, would often stumble upon the remnants of woolly mammoths that died out 10,000 years ago. But as the ground thaws, Siberia is revealing its ancient treasure hoard faster than ever. Now, fuelled by Chinese demand for ivory, tusk hunters are racing to retrieve so-called “ice ivory” from the Siberian permafrost.

An estimated 80 per cent of Siberian mammoth tusks end up in mainland China, via Hong Kong, where they are carved and turned into elaborate sculptures and trinkets. Russia exported 72 tonnes of mammoth tusk in 2017 but exports have dropped off as a growing underground trade in tusks appears to be eating into the official trade. While collectors can obtain licences, they increasingly complain of pressure from the authorities who confiscate their finds and demand high tariffs. To avoid losing business, many are sidestepping existing regulations and selling their tusks quickly but for less money to Chinese dealers who come to buy them directly. Some see the legal mammoth trade as a relief valve that gives consumers an alternative to elephant ivory. But is the shadowy trade in the extinct species putting even more pressure on one of the world’s most endangered animals?

Tusk hunters use fire hoses to blast away the mud surrounding mammoth skeletons

Mammoth hunting is an enticing profession for the daring or desperate residents of Yakutia. All of the tusk hunters Chapple encountered in the isolated camp were local to the area, but each one had a different motivation that brought them to search beneath the permafrost. One was a self-made millionaire through the mammoth tusk trade, some had full-time jobs during the rest of the year, and others broke into the business more recently after watching viral videos that made the excavations look like a quick win. Everybody knows the drill: pick a spot and blast away. “A lot of these guys are in quite desperate situations,” says Chapple. Many take out bank loans to finance the petrol needed for the pumps. “If they can just get one of these tusks, it can change their lives.”

Some use powerful firefighter pumps to melt away the ice and bore deep underground. Others burrow labyrinthine caverns under the ground and navigate below the dripping mud with huge chunks of ice hanging over them. “All it takes is a roof collapse and they’re entombed forever,” says Chapple, who photographed the “mammoth hunt” for Radio Free Europe, a US government-funded broadcaster in Eastern Europe. It’s dangerous but lucrative work where a lucky few could strike it rich. For most collectors in this impoverished region, though, an entire season of backbreaking labour in the mud will end up losing them money.

Along this 120km stretch of river, the only movement interrupting the excavations are occasional patrol boats with environmental protection officers accompanied by police looking for hunters who don’t have a licence to sell their finds legally. If word gets out that a boat is approaching, “they throw camouflage netting over the equipment and melt away far into the forest like Chechen guerrillas,” says Chapple.

Although the trade is still not fully regulated, searching for and selling mammoth tusks is completely legal in Russia as long as collectors obtain a licence. Alexei – a licensed dealer who asked to be identified by a pseudonym – has been exporting mammoth tusks for seven years. In the past two years, his business has been struggling as the black market really started taking off. With Russian authorities slowing down the legal trade, his Chinese customers are starting to turn to smugglers for their supply of mammoth ivory instead. “We suffer big losses,” he says. “Almost two tonnes of legally mined material were taken from me for inspection. A year-and-a-half has passed and the tusks are still being examined.”

Confiscating ivory from licensed collectors and dragging out checks for years may be an attempt to better control the trade, says Alexei, but it risks achieving quite the opposite. “It kills the legal market in Yakutia and pushes people to do illegal business.” Due to the nature of the business, it is difficult to estimate how many tusks are exported illegally, but Alexei believes it could be as much as 50 per cent today, compared with 20 per cent in 2016. These underhand deals not only make it impossible for authorities to keep the trade in check, there is one other beneficiary that misses out on the ancient treasures: science.

Since the 1990s, the Academy of Sciences of the Sakha (Yakutia) Republic (ASSR) has received many rare specimens from licensed ivory collectors that it could not otherwise afford, including carcasses of woolly mammoth, woolly rhino and cave lion cubs. Where collectors might have left the skulls and bones of prehistoric megafauna scattered around excavation sites in the past, they now know their value and hand them over to scientists for free. “We have an agreement with these guys,” says Valerii Plotnikov, a senior researcher at the ASSR. A collector remains the owner and receives a cut of the profits when the specimens are exhibited abroad.

Last year, a Yakutia resident unearthed a severed wolf head estimated to be around 40,000 years old. With a full head of hair, fangs, tongue and even brain tissue largely intact, Plotnikov’s team could use DNA analysis and CT scanners – a tool that uses x-rays to create a 360-degree image of internal organs and tissues – to study this ancient predator and compare the genetic information to that of modern wolves.

As an adviser to the Russian Ministry of Culture, Plotnikov takes photos and measurements of the mammoth tusks the collectors bring into Yakutsk in order to estimate their age, size and weight – and determine their cultural value. This allows collectors and dealers to request a licence to export the tusks from Moscow to China. It’s a months-long process that has now become even more complex. Three months ago airport police in Yakutsk confiscated several tonnes of tusks from a licensed collector and are still holding them. The slow checks end up losing collectors money. As a result, many start selling their goods on the black market, and the long-established trading companies that used to buy tusks in bulk and sell them on to China are now being undercut by illegal traffickers. “If the whole business becomes illegal, scientists will not have a chance to take measurements of these tusks,” says Plotnikov. “It’s terrible, but what can we do?”

A single tusk can sell for tens of thousands of pounds

Lucy Vigne is a very different kind of ivory hunter. Determined to combat ivory smuggling and elephant poaching, Vigne has spent years investigating the global ivory trade with her late colleague Esmond Martin. When the pair last visited the southern Chinese city of Guangzhou, they primarily came across mammoth ivory in specialty shops. In 2011, the independent researchers counted and photographed 6,541 items in 30 outlets – some of them with posters in the windows advertising their mammoth wares. Because of the brown outer layer, large cracks and stains, the mammoth ivory available for purchase was mostly carved into sculptures and figures, some priced at £7,800, rather than mass produced into jewellery and chopsticks as was the case with elephant tusks.

Mammoth ivory has steadily gained popularity since the early 2000s but, when China banned the import and sales of elephant ivory in 2017 to solve the poaching crisis, ivory carvers and vendors started switching to the ancient material en masse. “The carvers in China are some of the best in the world and have great expertise in carving all sorts of materials, so they are willingly adapting to it,” says Vigne.

Vigne, who was raised in England and now lives in Kenya, returned to the port city in late 2018 to find the number of mammoth ivory items for sale had soared. Guangzhou is just two hours away from Hong Kong so bringing in mammoth tusks in bulk is simple and profitable. With a wealthier population interested in luxury goods, buyers in Guangzhou – a city famous for both its ivory carving factories and shops – seem to have accepted the elephants’ long-extinct ancestors as an authentic substitute. While Russian “ice ivory” was sold as an exclusive collector’s good in the past, smaller items such as pendants, bangles and beaded bracelets have become affordable substitutes for the mass market. A small pendant, for instance, can sell for as little as 250 yuan (£27) in the market areas for jade stones, jewellery and antiques. Retailers in the new shopping centres and airport gift shops charge several times that price.

When elephant ivory was legally and widely available in mainland China, some vendors struggled to persuade consumers into buying mammoth items and ended up closing their outlets due to low sales. Those specialising in mammoth ivory and catering to a wealthier clientele were already doing better when Vigne and Martin visited in 2011. With lower imports and rising prices, these specialist vendors believed, the limited commodity would eventually become a profitable investment.

For the average buyer, Vigne says, the fact that their ivory trinket started life attached to a woolly mammoth doesn’t make it any less attractive. With an estimated ten million mammoths still buried in Siberia’s permafrost, the ancient animal outnumbers the 350,000 African elephants by far. Chinese consumers will happily buy mammoth ivory as long as it resembles the white ivory they are used to. Traditional ivory carving goes back to the 14th century and, historically, was the preserve of emperors, scholars and the upper-class. Today, ivory is still a status symbol for the new middle class, often cherished for its aesthetic. “Although people aspire to own ‘ivory’, in reality, many would be unable to distinguish between elephant and mammoth ivory or even ivory substitutes,” says a spokesperson from TRAFFIC, a wildlife trade monitoring group working in the region.

But the strong similarities between the two makes telling the difference between legal mammoth ivory and illegal elephant ivory difficult. When mammoth tusks are traded in their entirety, they are relatively easy to identify because, unlike those of elephants, they have a brown, outer peel and tend to be larger and twisted. To identify the origin of a piece of tusk or carved sculpture, dealers and vendors have to resort to a photocopier or scanner and take a photo of the stacked chevron-like pattern visible in a cross-section of ivory. Closest to the root of the tusk, which is essentially an elongated tooth, it’s easy to discern these intersecting lines. If the angle these lines meet at is less than 90 degrees, the tusk belongs to a mammoth. If it is over 90 degrees, it is that of an elephant. It is not a fool-proof system, though, especially if the pieces are small, painted and carved upon.

“It’s easier to mix smaller items of elephant and mammoth ivory. That does happen, either accidentally or because a vendor is not experienced since they used to be sold in the same shops,” says Vigne. When scouring the market areas and shops of southern China before the ban, she would ask to see both mammoth and elephant ivory in shops. “If one is looking at several on a counter, it’s very difficult for the shopkeeper to remember which pendant came from where because they can look identical,” says Vigne.

While elephant ivory was banned from mainland China in 2017, it will be available in Hong Kong until 2021. This left a four year window to potentially smuggle ivory purchased legally in Hong Kong into southern China. It is not clear how much mammoth ivory ends up in mainland China every year, but customs data shows that on average 36 tonnes of raw tusks and unworked tusk pieces are brought into Hong Kong every year as there is no import tax. Of that, 29 tonnes of mammoth tusks are re-exported to mainland China.

Recent investigations by TRAFFIC suggest that a few shops in China, Hong Kong and even the US have labelled elephant ivory as “mammoth” or “bone”. Since law enforcement officials are unable to check every single item sold in a store, vendors might sell elephant ivory illegally, under the guise of it being mammoth ivory. The state of New York prohibits the domestic sale of elephant ivory since 2014 and mammoth ivory since 2016 and convicted a Manhattan-based antiques vendor in 2017 of intentionally mislabelling elephant as mammoth ivory during the transition period. Mammoth ivory is also banned in India. There is no comprehensive assessment that demonstrates how widespread the practice is in China and where on the trade route the laundering may be happening, because mammoth comes from Russia and elephant from Africa. “What we’ve got to remember is that raw [elephant] tusks are being smuggled off the African continent hidden in large shipments by criminal networks,” says Vigne. “They’re not laundering elephant ivory. It would look rather odd if tusks came out of Africa and are labelled as mammoth ivory.” Those wanting to crack down on the illegal elephant ivory trade and potential mammoth laundering will have to map out the marketplace first.

The density of animal remains in this region suggest that it was once a swamp or bog that trapped animals

Mammoth ivory has been touted as an “ethical” alternative for the continuing illegal ivory trade that is threatening an entire living species with extinction, but at what cost? Earlier this year, economists from Texas A&M University and the University of Calgary investigated how the supply of unearthed mammoth ivory affected the poaching of wild elephants between 2010 and 2012. They estimated that the 80 tonnes of mammoth ivory that were exported from Russia in an average year reduced poaching from 55,000 elephants per year to 34,000.

Conservationists and campaigners, on the other hand, see the mammoth ivory trade as a way of sustaining a criminal industry and fear it could provide a loophole for intentional mislabelling and laundering. In August, delegates taking part in CITES, the world’s biggest conference on wildlife trade, debated whether woolly mammoths should become the first extinct species to be listed as endangered in an attempt to regulate the trade and clamp down on ivory smuggling. As the trade in mammoth ivory is almost unregulated and undocumented today, the rationale behind the proposal put forward by Israel was to remove any loopholes that could facilitate mislabelling and laundering of illegal elephant ivory. With all the complexities trade regulations entail, would a total ban on mammoth ivory stop the trade altogether?

Douglas MacMillan, a University of Kent professor focusing on the economics of conservation, isn’t convinced. “A mammoth ivory ban would drive prices for elephant ivory higher and therefore increase the incentive to poach them,” he says, adding that demand and prices for elephant ivory have been falling rapidly in China in the last five years – as a result, many ivory carving factories had shut down by the time the ban on elephant ivory came into force in 2017.

And it appears that demand for ivory might be dwindling anyway. In September, a WWF-funded survey of 2,000 people in China found that 73 per cent of respondents would not buy ivory, compared to 57 per cent in 2017 before the domestic ban on elephant ivory went into effect. Respondents cited concerns about the extinction of elephants and the cruelty related to ivory trade. Most consumers are aware that elephant ivory is illegal, which seems to have rubbed off onto mammoth ivory. “Most ordinary people do not understand the difference between a mammoth and an elephant, and since the ban on elephant ivory, they simply are afraid to buy anything,” says Russian dealer Alexei.

Israel ended up withdrawing its motion to regulate the trade in long-extinct woolly mammoths, pending further research into the extent of laundering and mislabelling. But there are still major question marks around what stockpiles exist, where manufacturing and sales takes place and how laundering of elephant ivory could be prevented. With a supply chain stretching out across three continents, if not more, the true scale of the mammoth ivory trade will remain in the dark unless traders and governments are willing to publicly release their export and import figures. Until then, any possible solutions will have to be put on ice.

October 29, 2020

Mammoths and Men

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For five months Karl Gorokhov has tracked his ancient prey across a desolate island in the East Siberian Sea, slogging 18 hours a day over the icy tundra. He is cold and exhausted, with a hunger so primal that he has been reduced to eating seagulls. Even the two polar bears that attacked his camp were famished; their stomachs, slit open after they were shot dead, were empty. Gorokhov, a 46-year-old with wind-chapped cheeks and a scraggly, reddish beard, heads out every day past the nine graves near his camp—the final resting places, he presumes, for unlucky souls who came to the island to escape the Soviet gulag.

Gorokhov is running out of time. Late summer blizzards are howling across Kotelnyy Island, 600 miles north of the Arctic Circle, and the deep freeze of another northern winter looms. His fingers and palms start to itch. It’s “a lucky sign,” Gorokhov said later. The itching usually strikes when he’s on the verge of finding what he’s looking for: the ivory tusks of a mammoth.

The shaggy giants that roamed northern Siberia during the late Pleistocene epoch died off about 10,000 years ago, though isolated populations lingered on islands to the north and east, the last dying out some 3,700 years ago. The mammoths’ tusks, which could spiral to more than 13 feet, are reemerging from the permafrost—and fueling a trade that benefits the people of Arctic Siberia, including the native Yakuts, an Asiatic ethnic group that speaks a language of Turkic origin. For nearly a decade Gorokhov has been a tusk-hunting pioneer, exploring one of the world’s most inhospitable expanses. Now, trusting his itchy fingers, he scours the tundra until he almost trips over the tip of a tusk. “Sometimes the tusk just appears in front of you,” he says, “as if it were guiding you all along.”

It takes Gorokhov almost 24 hours of continuous digging to extract the tusk from the pebbly ice below. The specimen that emerges is as thick as a tree trunk—150 pounds—and in near-pristine condition. Before hauling the tusk away, Gorokhov tosses a silver earring into the hole he has dug, as an offering to the local spirits. If he gets the ancient relic safely home, it could fetch more than $60,000.

The trade in mammoth ivory barely existed when Gorokhov was born in northern Siberia in 1966, on the same day, May 5, as his namesake, Karl Marx. He remembers as a child seeing rotting tusks on the banks of the Yana River, near his fishing village of Ust-Yansk. Free enterprise was banned in the Soviet Union, and many locals considered it bad luck to disturb the tusks, which some believed came from giant molelike creatures that lived deep under the permafrost.

The journey from permafrost to market—nearly 90 percent of Siberia’s tusks end up in China—begins by small boat.

Still, the ancient tusks held Gorokhov in their spell. Growing up in Yakutiya, a resource-rich region nearly the size of India that’s inhabited today by fewer than a million people and is officially called the Republic of Sakha, he was told that the Earth’s creator got so cold flying over this region that he dropped a wealth of treasures: gold, silver, diamonds, oil. But it was his schoolteachers’ real-life stories about 17th-century pioneers trading in mammoth tusks that captivated Gorokhov. Years later he would find library books with photographs of early 20th-century explorers: bearded men standing on Kotelnyy Island, dwarfed by mammoth tusks, their boats groaning with stacks of ivory. “I always wondered if more tusks were out there,” Gorokhov says.

Nobody, not even Gorokhov, imagined that mammoth tusks would become an economic lifeline for a region that had been largely abandoned after the shuttering of Soviet-era mines and factories. (The population of Yakutiya’s Ust-Yanskiy District, which covers a swath of tundra three times the size of Switzerland, has dropped from 80,000 to just 8,000 in the past five decades.) Now hundreds, if not thousands, of Yakutiyan men have become tusk hunters, following their ancestors’ routes, enduring the same brutal conditions—and chasing the same Paleolithic beasts.

Nothing, however, has fueled the mammoth tusk trade more than the rise of China, which has an ivory-carving tradition going back thousands of years. Nearly 90 percent of all mammoth tusks hauled out of Siberia—estimated at more than 60 tons a year, though the actual figure may be higher—end up in China, where legions of the newly rich are entranced by ivory. The spike in demand has worried some scientists, who lament the loss of valuable data; like the trunk of a tree, a tusk contains clues about diet, climate, and the environment. Even Yakutiyans wonder how quickly this nonrenewable resource will be depleted. Millions of mammoth tusks, perhaps more, are still locked in Siberia’s permafrost, but already they’re becoming harder to find.

October 29, 2020

Characteristics Of Elk Tusk

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Elk are the second largest members of the deer family. Adult male elk, referred to as bulls, attain their largest size at 7 years old. Once fully grown, a bull elk averages 5 feet tall at the shoulders and can weigh between 700 and 1100 pounds. Female elk, known as cows, weigh between 500 and 600 pounds, and stand an average of 4.5 feet at shoulder height. Only bulls have antlers.

Antlers
Antlers play a very important role in mate selection. Antlers, unlike the horns of bison, are shed every spring and a new set is grown. Antler growth is in preparation for the mating season, which primarily occurs in September and October. Large antlers advertise dominance and the ability to defend against predators and other bulls. Therefore, female elk will generally select a dominant bull with large antlers. Antlers can weigh up to 40 pounds per set. Velvet, which covers antlers during the growth phase, carries blood to the growing bone tissue. During the summer months, antlers can grow up to one inch per day, making it the fastest growing bone known.

The blood flow to the antlers stops in August, when the antlers have reached their full size. At this point, the velvet covering dries and falls off or is rubbed off on trees or shrubs.

Teeth
Teeth in elk are similar to other deer except for the presence of upper canine teeth. An elk’s canine teeth, made of ivory, are unique and were highly prized by both Native Americans and European settlers. The “ivories” (also called tusks, whistlers, or buglers) were primarily used as decorative beads, pendants, and necklaces, and were very valuable due to their rarity. The elk’s molars and incisors provide the best indication of the animal’s age.

Mating
The gestation period of elk is approximately 8.5 months, with calves born from late May through early July. Cows separate from the herd and go into hiding during calving. Calves are hidden during the first few weeks following birth until they are able to run from predators. A cow usually gives birth to a single calf, but on rare occasions there will be twins. At birth a calf weighs about 35 pounds.

Elk form herds which offer protection against predators. Cows and calves live in groups, but are generally only accompanied by bull elk during the mating season, or “rut.” The rut occurs in autumn.

Elk begin “bugling”—their signature mating call—in early autumn. This is typically a good time to see and hear elk. (A recording of a bugling elk) The rut is characterized by harems, which are groups of cows and calves, controlled by a dominant bull. During other seasons, males can be found alone or in small bachelor groups.

elk herd

Habitat
Elk can live in a variety of habitats, including forests, meadows, and mountains. Their diet includes grasses, tree leaves, twigs, and shrubs. Bark, pine needles, and tree lichens are also eaten in smaller quantities. Elk eat an average of 3 pounds of food per day for every 100 pounds of body weight; therefore, a bull elk weighing 800 pounds would eat about 24 pounds of forage each day. Elk thrived in North America until the first Europeans began settling the area. Prior to their arrival, an estimated 10 million elk ranged across the United States. European settlers hunted elk to provide food for their families and because they feared the elk would compete with livestock. Also, market demands for elk products such as hides, antlers, and “ivories” encourage the harvest of elk.

Elk habitat was lost as thousands of acres were cleared for farms and developing towns. As a result of over-harvest and habitat destruction, elk populations began to decline, reaching a low of
90,000 by 1900.

By the 20th century, two of the six subspecies, including the Eastern elk which lived throughout the eastern United States, were extinct. Fortunately, Americans concerned with the survival of the elk called for regulated hunting seasons and initiated elk recovery programs.

For Your Safety
Elk appear relatively docile, but they can be unpredictable and dangerous. Do not approach or attempt to provoke them. Large animals should be respected at all times, especially bulls and cows with calves. Also, for your safety and for the elk’s safety, DO NOT FEED the animals.

Offering human food to elk (or any wild animal) is harmful in two ways:

It conditions the animals to view people as a food source, leading to the possibility of property damage and human injury; and
Human food is not healthy for the animals.

Cart

Introduction

Woolly mammoths and the biology of tusks

Results

Chemical composition and structure

Mechanical properties

Discussion

Conclusion

Methods

Data Availability

References

Acknowledgements

Interview Highlights

World

As Arctic Ice Melts, It’s A Free-For-All For Oil … And Tusks

The Two-Way

Good News For Elephants: China’s Price Of Ivory Has Plummeted

Wolly Mammoth tusks in our collections

In Ayrshire

HMS Blossom in Alaska

1. Mammoth Diets Included Some, Well, Interesting Things

2. Woolly Mammoths Roamed a Land That Was Cold but Not So Snowy.

3. Woolly Mammoths had Cold in Their DNA.

4. You Do Not Want to Mess With the Musth

5. New Evidence From Mammoth and Mastodon Fossils Hints at Humans as Prime Suspects in the Animals’ Disappearance. But the Jury is Still Out

Poaching and Habitat Loss: Clear Threats to Elephants

Why protect an extinct species?

Wait, you can trade mammoth ivory?

It’s not all mammoth

Is it woolly thinking?

A solution put on ice