Island Evolution and What's More: August 2008

Wednesday, August 6, 2008

'Hobbit' skull found in Indonesia is not human indeed

Since its first description in 2004, Homo floresiensis, or the Hobbit of Flores, has been attributed to a species of its own, a descendant of Homo erectus, Homo ergaster or another early hominid, such as Australopithecus. Non-believers however hold the new species for a pathological form of modern humans, Homo sapiens, or just a dwarf human like the Neolithic inhabitants of the very same island. Karen Baab and colleagues applied landmarks on the skull, and concluded Homo floresiensis is a species on its own, and related to hominins of 1.5 million years ago. We did the same, half a year earlier, and reached similar conclusion but dare to put one step further. We applied geometric morphometric analysis to the type skull of Homo floresiensis (LB1) and compared it with skulls of normal Homo sapiens, insular Homo sapiens (Minatogawa Man and Neolithic skulls from Flores), pathological Homo sapiens (microcephalics), Asian Homo erectus (Sangiran 17), African Homo habilis (KNM ER 1813), and Australopithecus africanus (Sts 5). Our analysis includes specimens that were highlighted by other authors to prove their conclusions. The geometric morphometric analysis separates the 'hobbit' from all modern humans, thus including both the pathological and the insular forms. It is further impossible to separate the 'hobbit' skull from Homo erectus. The very early hominin Australopithecus falls separately from all skulls.

Visual inspection of the skulls learned that the cranial shape of Homo floresiensis is most close to that of Homo erectus and not to that of any modern human. Apart from cranial shape, some features of Homo floresiensis are not unique but are shared with other insular taxa, such as the relatively large teeth (shared with Early Neolithic humans of Sardinia), and changed limb proportions (shared with Minatogawa Man).

We thus conclude that Homo floresiensis is a direct descendant of Asian Homo erectus and has no relation neither to primitive australopithecines nor to modern Neolithic pygmy people of Flores.

By G.A. LYRAS, M.D. DERMITZAKIS, A.A.E. Van der GEER, S.B. Van der GEER, J. De VOS. 2008. The origin of Homo floresiensis and its relation to evolutionary processes under isolation.© 2008 The Anthropological Society of Nippon

For free pdf, click here http://users.uoa.gr/~glyras/projects/Homo-floresiensis.pdf

Or go to the publisher http://www.jstage.jst.go.jp/browse/ase

The effect of insularity on the five-horned deer Hoplitomeryx (Late Miocene, Italy)

Island studies increase our understanding of the effects of habitat fragmentation. The study of the Tertiary paleo-island Gargano is an important contribution, because of the long-term isolation under less fluctuating climatic conditions, free from anthropogenic influences; such a situation does not exist in the Quaternary period nor in the Holocene period. This makes the Gargano a unique case to study the effects of insularity in isolation. Here, a highly endemic, unbalanced vertebrate fauna evolved including the five-horned deer Hoplitomeryx. Its post-cranial material contains four size groups, based on the metapodals. In this study, the humerus and radius are described. The question whether the morphotypes are chronomorphs or ecomorphs is addressed. Sexual dimorphism is ruled out as the underlying principle of size separation in this case, based upon body mass estimations and data from living deer. Chronomorphs is the best explanation for the Megaloceros cazioti lineage (Pleistocene, Sardinia) and the Myotragus balearicus lineage (Pliocene–Holocene, Mallorca). Ecomorphs are a better explanation for the size groups of Candiacervus (Late Pleistocene, Crete) and Cervus astylodon (Late Pleistocene, Ryukyu Islands, Japan). An adaptive radiation into several trophic types took place, promoted by the ecological meltdown of the ancestral niche. The drive behind this speciation is increased interspecific competition. For Hoplitomeryx, although the hypothesis of chronomorphs cannot be discarded, that of ecomorphs seems most likely, based upon the coexistence of two or more size groups per fissure, and upon the presence of a huge morphotype, larger than mainland species, in the younger fissures.

Read more in VAN DER GEER A.A.E. (2008). The effect of insularity on the Eastern Mediterranean early cervoid Hoplitomeryx: the study of the forelimb. Quaternary International 182, 1: 145-159. See http://dx.doi.org/10.1016/j.quaint.2007.09.021 or ask me a pdf (geeraae@geol.uoa.gr).

For more general information of this enigmatic Late Miocene 'deer', see my Wikipedia page at http://en.wikipedia.org/wiki/Hoplitomeryx

Animals in Stone

The art history of South Asia covers a time span of roughly four and a half thousand years. During this period, a vast number of animal stone sculptures has been produced, ranging from the pre-historic period till today and covering a great variety of motifs and imagery in different regions and religious traditions. Even so, the number of studies devoted to these animal sculptures has remained extremely limited. The present book aims at filling this knowledge gap. With this richly illustrated book, the first of its kind, Van der Geer offers a comparative study of the ways in which various animals have been depicted and a lucid analysis of the sculptors’ treatment of their “models”: living animals. The art history of sculptured animals is contextualized with a description of the use of animals as can be read from ancient texts, archaeological evidence and contemporaneous culture. In doing so, parallels as well as differences in style or iconography are highlighted, elucidating the variety of animal depictions across regions, religious contexts and through time. The corpus of discussed material ranges from Indus seals, stupa panels and railings, monumental temples from North and South India, non-religious palace and fort architecture to loose sculptures in museum collections.

My publications (a selection, in chronological order)

2014 Van der Geer A.A.E. Parallel patterns and trends in functional structures in island mammals. Integrative Zoology. Accepted article. doi:10.1111/1749-4877.12066
2013 Van der Geer A.A.E. et al. Body size evolution of palaeo-insular mammals: temporal variations and interspecific interactions. Journal of Biogeography 40, 1440–1450.
2010 Van der Geer A.A.E. et al. Evolution of Island Mammals: Adaptation and Extinction of Placental Mammals on Islands. Blackwell Publishing, c. 384 pp.
2008 Van der Geer, A.A.E. The effect of insularity on the Eastern Mediterranean early cervoid Hoplitomeryx: the study of the forelimb. Quaternary International 182, 1: 145-159.
2008 Van der Geer, A.A.E. Animals in Stone. Indian mammals sculptured through time. Handbook of Oriental Studies, Section 2 South Asia (ed. J. Bronkhorst). Leiden: Brill. lxxii, 814 pp, c. 700 ill, index. Hardback. ISBN 978 90 04 16819 0.
2008 Van der Geer A.A.E., Dermitzakis D.M. Dental eruption sequence in the Pliocene Papionini Paradolichopithecus arvernensis (Mammalia: Primates) from Greece. Journal of Vertebrate Paleontology 28 (4): 1238-1244.
2008 Van der Geer A.A.E. et al. Hoe dieren op eilanden evolueren. Majorca, Ibiza, Kreta, Sardinie, Sicilie, Japan, Madagaskar, Malta. Utrecht: Veen Magazines; ISBN 978 908571 169 8.
2006 Van der Geer, A.A.E., Dermitzakis, M. Relative growth of the metapodals in a juvenile island deer: Candiacervus (Mammalia, Cervidae) from the Pleistocene of Crete. Hellenic Journal of Geosciences 41, 1: 119-125.
2006 Van der Geer, A.A.E., De Vos, J., Lyras, G., Dermitzakis, M. New data on the Pleistocene Cretan deer Candiacervus sp. II (Mammalia, Cervinae). Courier Forschungsinstitut Senckenberg 256: 131-137. Frankfurt am Main.
2006 Van der Geer, A.A.E. et al. Crete before the Cretans: the reign of dwarfs. Pharos 13: 121-132. Athens: Netherlands Institute.
2006 Van der Geer, A., Dermitzakis, M., De Vos, J. Fossils and myths in North India: is there a connection between the Siwalik Hills and the Mahābhārata? The 19th European Conference on Modern South Asian Studies, 27-30 June 2006, Leiden the Netherlands. Abstracts: p 124. Leiden: International Institute for Asian Studies.
2006 Sondaar, P.Y., Van der Geer, A.A.E., Dermitzakis, M. The unique postcranial of the Old World monkey Paradolichopithecus: more similar to Australopithecus than to baboons. Hellenic Journal of Geosciences 41, 1: 19-28.
2006 Lyras, G.A., Van der Geer, A.A.E., Dermitzakis, M.D., De Vos, J. Cynotherium sardous, an insular canid (Mammalia: Carnivora) from the Pleistocene of Sardinia (Italy), and its origin. Journal of Vertebrate Paleontology 26 (3): 735-745.
2006 Lyras, G. Van der Geer, A. Adaptations of the Pleistocene island canid Cynotherium sardous (Sardinia, Italy) for hunting small prey. Cranium 23, 1: 51-60.
2006 Dermitzakis, M., Van der Geer, A.A.E., Lyras, G. Palaeopathological observations on a population of fossil deer from the Late Pleistocene of Crete. In: Kalofourtis, A., Papadopoulos, N., Spiliopoulou, C., Marabellas, K., Chatzioannou, A.. Volume in Honor of Prof. A.S. Koutselinis, pp. 43-51. [in Greek with English summary].
2006 Dermitzakis, M., Roussiakis, S., Van der Geer, A.A.E. Sto Mouseio – Mosasaurus. With English summary. National and Kapodistrian University of Athens, Museum of Palaeontology and Geology, Athens; 55 pp.
2005 Van der Geer, A.A.E. The postcranial of the deer Hoplitomeryx (Mio-Pliocene; Italy): another example of adaptive radiation on Eastern Mediterranean Islands. Monografies de la Societat d'Història Natural de les Balears 12: 325-336. Palma.
2005 Van der Geer, A.A.E. Island ruminants and the evolution of parallel functional structures. In: Cregut, E. (Ed.): Les ongulés holarctiques du Pliocène et du Pléistocène. Actes Colloque international Avignon, 19-22 septembre. Quaternair, 2005 hors-série 2: 231-240. Paris.
2005 Sondaar, P.Y., Van der Geer, A.A.E. Evolution and Extinction of Plio-Pleistocene Island Ungulates. In: Cregut, E. (Ed.): Les ongulés holarctiques du Pliocène et du Pléistocène. Actes Colloque international Avignon, 19-22 septembre. Quaternair, 2005 hors-série 2: 241-256. Paris.
2003 Lyras, G.A., Van der Geer, A.A.E. External brain anatomy of the Canidae. Zoological Journal of the Linnean Society 138: 505-522. London. doi: 10.1046/j.1096-3642.2003.00067.x.
2002 Van der Geer, A.A.E., Sondaar, P.Y. The postcranial elements of Paradolichopithecus arvernensis (Primates, Cercopithecidae, Papionini) from Lesvos, Greece. Annales Géologiques des Pays Helléniques 1e Série 39, A: 71-86.
2000 Sondaar, P.Y., Van der Geer, S. Mesolithic environment and animal exploitation on Cyprus and Sardinia/Corsica. In: Mashkour, M., A. Choyke & M. Buitenhuis (eds). Proceedings of the IVth ASWA Symposium, IVA: 67-73. Paris.
1999 Van der Geer, A.A.E. On the astragalus of the Miocene endemic deer Hoplitomeryx from the Gargano (Italy). Deinsea 7: 325-336. Rotterdam: Natuurmuseum.
1998 Van der Geer, A.A.E. The Bhāsa Problem. A statistical research into its solution. Ph.D. Thesis Rijksuniversiteit Leiden; 243 pp.
1996 Van der Geer, A.A.E. Samskrtabhāsa B2, Sanskrit voor gevorderden; 233 pp.
1996 Van der Geer, A.A.E. Samskrtabhāsa B1, cursus Sanskrit voor beginners; 366 pp.
1995 Van der Geer, A.A.E. Woordenboek Nederlands-Sardijns. Leiden; 240 pp.
1995 Van der Geer, A.A.E. Isco sa limba mea. Sardijns in 10 lessen. Leiden; 229 pp.