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Home , Captive elephants, Choerolophodon, Deinotheriidae, Elephantida, Elephantidae, Moeritherium

The World of - International Congress, Rome 2001

Elephants and other Proboscideans: a summary of recent findings and new taxonomic suggestions

J. Shoshani1, W.J. Sanders2, P. Tassy3 1 Department of Biology, University of Asmara, Asmara, Eritrea (Horn of ); Research Foundation, Bloomfield Hills, Michigan, USA - [email protected], [email protected] 2 Museum of Paleontology, University of Michigan, Michigan, USA [email protected] 3 Museum National d’Histoire Naturelle, Laboratoire de Paleontologie, Paris, [email protected]

SUMMARY: Today we recognize 165 and subspecies of proboscideans, classified in 42 genera and 8 families. Of these, three species are extant: the forest (Loxodonta cyclotis), bush African elephant (L. africana), and the ( maximus, with three subspecies). In 2000, the esti- mated world population of elephants was just over one half million; most are African elephants. New taxa include Mammutida and , and one proposed here: Plesielephantiformes, as a sister taxon to Elephantiformes. Neontological research is currently under way on these areas of investigation: anatomy and physiology on eye, trunk, hyoid apparatus, , hearing, reproduction, ecology, behavior, and conservation. Topics for future research include: phylogenetic positions of Anthracobunids, , tetralophodont , and , and intra-familial relationships among Loxodonta, Elephas and Mammuthus, and also continuing studies on brain, reproductive biology, and conservation, emphasizing educational approaches.

1. INTRODUCTION rocco, Stegodon sondaari (by Van den Bergh 1997) from named in honor of Paul Y. Henry Fairfield Osborn published his monu- Sondaar [Note: Van den Bergh placed Stegodon mental two-volume in 1936 and in the family , contra other investi- 1942 (Osborn 1936, 1942). In 1996 the first and gators who place Stegodon in the family Ste- third authors of this contribution edited another godontidae (more below)], and volume by the same name that reviewed ad- aegyptensis (by Sanders and Miller, in press) vances in our knowledge since Osborn (Shoshani from Egypt. In addition, Loxodonta cyclotis & Tassy 1996). In this presentation, we build on (Matschie 1900), was elevated from subspecies the 1996 volume to summarize recent findings to species level (Grubb et al. 2000). Results on living and extinct proboscideans and propose from Molecular findings (cytochrome b), how- some taxonomic revisions and additions. ever, indicate that of the one dozen of sequences In 1942, following Osborn, 352 species and of L. cyclotis not all samples clustered to form a subspecies of proboscideans were recognized; clade (there were two exceptions: two savanna they were classified in 40 genera, and 8 families. elephants had forest haplotype!) (Debruyne in In 1996, corresponding numbers were 162, 40, preparation). Based on the work of Inuzuka and 8 (not the same genera and families). Most (1977a, b) and our morphological observations, recently a new and three new species have as well as studies of skeletons of P. naumanni, been described: escuilliei (by we suggest that is a bona fide Gheerbrant, Sudre & Cappetta 1996) from Mo- genus, instead of a subgenus of Elephas. 676 Elephants and other proboscideans: a summary of recent findings and new taxonomic suggestions

These descriptions and a revision bring the to- numidotheres. Other hypotheses to be tested tal of living and extinct proboscideans to 165 include whether is a/the com- species (classified in 42 genera, and 8 families). mon ancestor of Mammutida (or a sister-taxon Of these three species, two are monotypic and to it), and also whether is a/the com- one is with three subspecies are alive today: the mon ancestor of Elephantida (or a sister-taxon forest African elephant (L. cyclotis), the bush to it). Presentations during this ITC-8 meeting African elephant (L. africana), and the Asian (Sun City South Africa) and those to be pre- elephant (E. maximus). The Asian elephant is sented in Rome (Italy) will include these top- believed to include three subspecies (Shoshani ics: new finding of proboscidean remains in & Eisenberg 1982): the Sumatran Asian elephant Ethiopia, Eritrea; Schreger pattern on tusks; (E. m. sumatranus), the mainland Asian elephant frozen (finding of the Jarkov mam- (E. m. indicus), and the Sri Lankan Asian elephant moth); relationships within the family Ele- (E. m. maximus) [sequence of listing represents phantidae, and subjects on anatomy, physiolo- an evolutionary trend, Shoshani 2000]. gy, ecology, and conservation. As of the 2000, the average estimated population of elephants in the world was just 3. over half a million (minimum 329,663, maxi- mum 706,090). Of these, there are 278,205 – 3.1 Topics investigated 637,599 African elephants of both species in the wild (Marchant et al. 2000) and 748-808 in cap- Current investigations are being carried out tivity (Shoshani, S.L. 2000), and 36,450-50,250 on the eye (do elephants see colors?); on trunk Asian elephants in the wild (Sukumar & Santi- anatomy and physiology (ongoing research; apillai 2000) and 14,260-17,433 in recently a team of investigators from Kansas (Shoshani, S.L. 2000). State University has been investigating the proboscis from a respiratory perspective); on 2. PALEONTOLOGY, INCLUDING the hyoid apparatus (anatomy and physiology; two papers are published in this volume, i.e. The classification of the 165 proboscidean Shoshani et al. 2001; Shoshani & Marchant taxa into 42 genera and 8 families is slightly 2001), summarizing its functions as tongue different from the 1996 publication. Subfami- support, resonating chamber, and for water lies and tribes and higher categories were storage); and on the brain (gross anatomy and added to elucidate cladistic findings. In addi- histological investigations one paper has been tion, we now include (sub- presented at the 8th Theriological Congress, family Choerolophodontinae) in the family Sun City, South Africa, and one again is in this Gomphotheriidae (contra Tassy 1985). New volume, i.e. Kupsky et al. 2001). In addition, taxa include Mammutida and Elephantida research is being conducted on reproduction (Shoshani et al. 1998), and one we propose in the wild and in captivity (immunological here, Plesielephantiformes as a sister taxon to techniques to prevent pregnancy, and artificial Elephantiformes [Plesielephantiformes in- insemination), on behavior (infrasonic com- cludes: Numidotheriidae, Barytheriidae, and munication aspects investigated in the field ; Elephantiformes includes: and laboratory observations, e.g. Meng et al. Palaeomastodontidae Phiomiidae, Mammuti- 1997). Other topics include Thailand elephants dae, Gomphotheriidae, tetralophodont gom- “play music” in an orchestra, and adult ele- photheres, , and Elephantidae]. phants “mentor” young unrelated elephants. The suggested synapomorphy for Plesiele- phantiformes is bilophodonty. Problem may 3.2 Conservation arise since it is possible that the lophodonty of deinotheres, for example, may not be homolo- After the 2000 CITES (Convention on Inter- gous with lophodonty of Phosphatherium and national Trade in Endangered Species of Wild 677 The World of Elephants - International Congress, Rome 2001

Fauna and Flora) meeting in Nairobi, South dence for early hominid dispersal east of Africa’s elephant population was transferred to Wallace’s Line. PhD Dissertation, Utrecht Appendix II but no further permission was grant- University, 364 p.. ed to any party to export for commercial Debruyne, M.R. In preparation. Molecular Phy- purposes. All other African populations are list- logeny of the Elephantidae: how far do the ed in Appendix I CITES. Elephas maximus is mitochondrial studies conflict. placed in Appendix I of CITES. Gheerbrant, E., Sudre, J. & Cappetta, H. 1996. A Palaeocene proboscidean from Morocco. Nature 383(6595): 68-70. 4. FUTURE RESEARCH Grubb, P., Groves, C.P., Dudley, J.P. & Shoshani, J. 2000. Living African elephants Future research topics might include whether belong to two species: Loxodonta africana anthracobunids should be included in the Pro- (Blumenbach, 1797) and Loxodonta cyclo- boscidea or as a sister group in the , tis (Matschie, 1900). Elephant 2(4): 1-4. whether Moeritherium should be placed in Ple- Inuzuka, N. 1977a. On a skull of Palae- sielephantiformes (a new taxon proposed here), oloxodon naumanni from saruyama, Shi- or as an earlier offshoot of Proboscidea, what is mosa-machi, Chiba Prefecture, central the taxonomic position tetralophodont gom- . Journal of the Geological Society photheres (i.e. those with four ridges on 4th pre- Japan 83: 523-536. molars, the 1st and 2nd molars), should Ste- Inuzuka, N. 1977b. On the origin of Palaeolox- golophodon and Stegodon be placed in the fam- odon naumanni - A comparative osteology ily Stegodontidae or in the family Elephantidae, of the cranium. Journal of the Geological and what are the intra-familial relationships Society Japan 83: 639-655. among Loxodonta, Elephas and Mammuthus — Kupsky, W.J., Marchant, G.H., Cook, K. & is it (Loxodonta (Mammuthus + Elephas)) as Shoshani, J. 2001 Morphologic analysis of suggested by the classical morphological data the hippocampal formation in Elephas max- (e.g. Maglio 1973), or (Elephas (Mammuthus + imus and Loxodonta africana with compar- Loxodonta)) based on some molecular data (De- ison to that of human. This volume. bruyne, in preparation)? In addition, it is sug- Maglio, V.J. 1973. Origin and evolution of the gested that studies should be continued on the Elephantidae. Transactions of The American form and function of the brain, and to find ef- Philosophical Society of Philadelphia, New fective method for birth control in the wild, and Series 63(3): 1-149. on ways to reduce operations. In the Marchant, G.H., Marsac, E.C. & Shoshani, J. field of conservation, we suggest that educa- 2000. African elephant population estimates tional approaches to co-existence of humans and and distribution: 1995/1999 update. Ele- wildlife should be emphasized, especially as the phant 2(4): 11. larger are ecological keystone, or super- Meng, J., Shoshani, J. & Ketten, D. 1997. Evo- keystone species. Some of these ideas were dis- lutionary evidence for infrasonic sound and cussed in Shoshani and Tassy (1996), and other hearing in proboscideans. Journal of Verte- in Shoshani (2000). brate Paleontology, 17: 64A. Osborn, H.F. 1936. Proboscidea: a monograph on the discovery, evolution, migration and 5. REFERENCES of the mastodonts and elephants of the world. Vol. I: Moeritherioidea, Bergh,van den, G.D. 1997. The late Neogene Deinotherioidea, Mastodontoidea. New elephantoid-bearing faunas of Indonesia York: The American Museum Press. and their paleozoogeographic implications: Osborn, H.F. 1942. Proboscidea: a monograph a study of the terrestrial faunal successions of the discovery, evolution, migration and of , and Java, including evi- extinction of the mastodonts and elephants 678 Elephants and other proboscideans: a summary of recent findings and new taxonomic suggestions

of the world. Vol. II: Stegodontoidea, Ele- Shoshani, J. Goren- Inbar N. & Rabinovitch, R. phantoidea. New York: The American Mu- 2001 A Stylohyoideum of Palaeoloxdon an- seum Press. tiquus from Gesher Benot Ya’aqov, Israel: Sanders, W.J. & Miller, E.R. In press. A new morphology and functional inferences. This proboscidean fauna from the early volume. site of Wadi Moghara, Egypt. Journal of Ver- Shoshani, J. & Marchant, G.H. 2001 The hyoid tebrate Paleontology. apparatus: a little known complex of bones Shoshani, S.L. (compiler). 2000. Captive elephant and its ‘contribution’ to proboscidean evolu- population of : 1988-1999, and tion. This volume. notes on other captive elephants elsewhere in Shoshani, J. & Tassy, P. (eds). 1996. The Pro- the world. Elephant 2(4): 63-71. boscidea: evolution and palaeoecology of Shoshani, J. (consultant ed.). 2000. Elephants: elephants and their relatives. Oxford: Ox- majestic creatures of the wild (Revised edi- ford University Press. tion). New York: Checkmark Books. Sukumar, R. & Santiapillai, C. 2000. Asian ele- Shoshani, J. & Eisenberg, J.F. 1982. Elephas phant population estimates and distribution: maximus. Mammalian Species, 182: 1-8. 1999 update. Elephant 2(4): 12. Shoshani, J., Golenberg, E.M. & Yang, H. 1998. Tassy, P. 1985. La place des mastodontes Elephantidae phylogeny: morphological ver- miocènes de l’ancien monde dans la phy- sus molecular results. Acta Theriologica 5: logénie des Proboscidea (Mammalia): hy- 89-122. [Erratum: on page 99, subfamily pothèses et conjectures. Thèse de Doctorat Elephantinae should include as en Sciences Naturelles, Université Pierre et shown in Table 1, page 93]. Marie Curie, Paris. Unpublished.

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