Alexandra van der Geer

Sandra van der Geer

I am a palaeontologist, specialised in aspects of evolution and biogeography of mammals on islands worldwide with emphasis on the Mediterranean and Southeast Asia. My Ph.D. is on adaptive radiation in extinct insular deer. Veterinary Medicine is my original background, hence my special interest in diet, ecology and morphology. I have ongoing collaborations with biogeographers and palaeontologists in international institutions, including the State University of New York, the American Museum of Natural History, Brown University of Rhode Island, the Field Museum of Natural History, the University of Wollongong and the University of Rome. Currently, I am shifting focus to developmental aspects of vertebrate evolution in isolation.


Evolution, biogeography, mammals, neogene, palaeontology, pleistocene, vertebrate palaeontology; island biogeography; extinctions; comparative morphology; mammalian system, insularity, à converis biodiversity, island mammals, palaeoecology, taxonomy

A.A.E. (Alexandra) van der Geer

Postdoctoral fellow
Endless forms

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My present research focuses at the evolution and extinciton of insular mammals worldwide, past and present.

An important aspect of the evolution of insular mammals is body size evolution, which roughly means that large mammals become small (dwarfism) whereas small mammals become large (gigantism). Many exceptions are known, and the factors that dictate the direction of body size evolution depend not only on the ancestral taxon but also on the island, the climate and the rest of the fauna, in other words, on the context. The extinction of insular mammals is perhaps an even more interesting phenomenon and sadly enough, an ongoing problem we face today on islands worldwide. The drivers behind these extinctions, however, are not always clear or known. A third research interest forms the role that animals play in human culture and folklore. The fauna surrounding human settlements always has an impact on human culture, and varies from use as food or utensils (meat, bone, sinew, antlers etc.) to art objects (decoration) and auspicious and religious symbols (zoomorphic divinities).

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A selection of the topics I am working on currently.

Changing invaders

How introduced rats have changed during their colonization of Pacific islands. Humans have been transporting vertebrates to islands worldwide since prehistory, often with dramatic impact on native fauna. These introduced species appear to change very…
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Of Mice and Mammoth

Of mice and mammoth: toward a general theory of body size across space and time. Body size is one of the major factors dictating physiological and anatomical processes. The direction of body size evolution in a species depends on many factors, internal as…
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Vatera two million years ago

The Early Pleistocene fauna of Lesvos (Greece) is known mainly from findings at Vatera near Polichnitos. The fossils are exhibited in a local natural history collection at the village of Vrissa, open to the public and under scientific curation by the…
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Animals in stone

Animals in stone- Indian fauna sculptured through time. 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…
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  • Evolutie van het paard. Graduate students, veterinary medicine (Utrecht University). Expo Naturalis Leiden, 2016 June 24 & 2014 June 27 & 2013 June 28, 2012 Septembre 6.
  • Sanskrit for beginners (part-time), 1996-1997, India Institute, Amsterdam.
  • Unggul Wibowo (Universitas Negeri, Yogyakarta). Insular Stegodons. Ongoing. Co-supervisor.
  • Jesse Hennekam (research intern, NBC Naturalis). Dental characteristics of Hoplitomeryx. 2014. Advisor.
  • Miranda Kouvari (University of Athens, Greece). The biogeography of extinction. 2016. Co-supervisor.
  • Aggeliki Zerri (University of Athens, Greece). The body size of cretan deer and its ecological significance. 2016. Co-supervisor.