We are interested in the different ways animal morphology and natural history becomes adapted to their biotic and abiotic environment. Some traits are extremely labile within species even across very restricted spatial scales (such as a group of islands) and temporal scales. Significant morphological changes can sometimes be detected over the course of a century or less, and presumably, they are evolutionary and adaptive. We study natural history, life history and morphological variation within and between species at different spatial and temporal scales, and then compare the patterns of variation shown in whole clades or regions, to search for common evolutionary mechanisms that drive them.
Our interests thus lay at an intersection of Evolutionary Biology, Biogeography, Macroecology and Zoology (mainly Herpetology, also Mammalogy and Ornithology, but we had and have projects on fish, arthropods, and even plants)
We use three main approaches to study the phenomena we are interested in: Macroecology, Museology and field-biology, with a bit of molecular and experimental biology thrown in from time to time for good measure.
The advantage of macroecology is that phenomena are studied at very large spatial, temporal and phylogenetic scales, enabling generalizations to be valid. A macroecological approach also allows us not to leave the air-conditioned lab during the Israeli summer. Or macroecological work mainly focuses on the diversity, life history and reproduction, ecology and island biogeography of reptiles. This often neglected group of terrestrial vertebrates is species rich (we anticipate that it will emerge as the largest tetrapod class, overtaking birds, within about a decade) and highly variable. Reptiles are beautiful and fascinating animals as everyone who has seen our two resident leopard geckos can attest. We are trying to erect a global dataset of the geographic ranges, ecological, morphological and natural history traits, as well as the phylogenetic relationships of reptiles that will allow us to seek patterns and test hypotheses regarding their evolution. We now also focus much attention on conservation and conservation planning, species assessments (Shai is the redlisting authority for the skink specialist group). This is done in collaboration with many scientists, especially Uri Roll, Reid Tingley, and Dave Chapple
With the help David Orme, Rich Grenyerand the members of ourGlobal Assessment of reptile distributions working-group, we examine factors that affect the distribution and evolution of lizards. We are trying mapping reptile distribution globally (With Anat in charge of snakes, Yuval of tortoises, crocs and the tuatara, Maria taking care of small-island reptiles, Gali in charge of improving maps in general, especially in trying to make Extent Of Occurrence Maps into Extent of Suitable Habitat maps. Our wonderful collaborator, Uri Roll is making the calls that require a responsible-adult. We study richness patterns, as well as other macroecological phenomena (relationships of features such as body size, range size, range position, etc.). Within this project Amir digitized the distribution of all of sub-Saharan Africa's lizards and amphisbaenians, to examine their congruence with other reptiles and other vertebrate classes. Enav studied the distribution of Palearctic lizards as well as their functional diversity, comparing them to the nested subset of Israeli lizards to examine the effect of scale on these metrics, as part of her PhD project (co-supervised by Yoni Belmaker).
We also play a lot with global datasets of vertebrate body size, and ask questions that mainly relate to size evolution on islands. Whenever we can we do this with Ally Phillimore (don’t call him Bede!), Pasquale Raia(e.g., Amy's project on the relationship between island area and the body sizes of mammals and reptiles and Maria's work on the relationship between insularity and life history) and Daniel Pincheira-Donoso. Maria also studies the macroecology of population density, in collaboration with Gordon Rodda. Gavin is looking at the factors (environmental and life-history) that are related to extrinsic and intrinsic mortality rates, which shape the variation in animal longevity and life history axes. Lior is studying the life history of snakes, its determinants and relevance for conservation. Anna meanwhile is studying the correlates of extinction risk in reptiles.
With Gopal Murali, a joint postdoc at ours and Uri Roll's the lab, we study diversification rates of squamates, and of vertebrates in general. We aim to simultaneously test multiple hypotheses related to causes of variation in diversification rates - see here for details.
"No statistical procedure can substitute for serious thinking about alternative evolutionary scenarios and their credibility" Westoby, Leishman and Lord, 1995. On misinterpreting 'phylogenetic correction. Journal of Ecology 83: 531-534.
Biodiversity, Phylogeny & Taxonomy of reptiles
We aim to help resolve the phylogeny, taxonomy and distribution of reptiles worldwide, and especially in Israel (where we also study fishes in Miachaela's project, insects in Guy's, Mammals in Adva's project and amphibians in David's). Thus, for example, we established the number, identity, phylogeography and distribution of Israeli "thin" racers of the Platyceps rhodorachis/saharicus/tesselata/ladacensis complex (Guy's MSc. project, in collaboration with Roi Dor, there is only one: P. saharicus), and Karin is working on the phylogeny and taxonomy of multiple reptile taxa(project in collaboration with Salvador Carranza) - with a focus on the Israeli species. We hope to get er to work on the greatest mess of all: Trapelus agamas. Marco is likewise studying the taxonomy of Israeli Pseudopus (with Daniel Jablonski), Tropiocolotes geckos and hopefully other taxa as well.
We examine and measure museum specimens of birds, mammals, amphibians and reptiles in museums across the world in order to study both current patterns of diversity and body size evolution – and temporal changes in both these axes that may have important conservation implications as well as teach us important lessons regarding the tempo and mode of evolution. Thus, for example, we study, body size changes in recent time in relation to cliamte change and other anthropogenic influences with Inon Scharf - this is part of the MSc project of Yuval (Baar).
We likewise acquired a large dataset of carnivore skull and teeth measurements (currently > 24600 measured specimens belonging to 248 – nearly all carnivore species) and a slightly smaller dataset (~1000 specimens) of treeshrew measurements. We use these data mainly to examine the forces that affect body size evolution (often in collaboration withTamar Dayan and Dan Simberloff), especially in relation to insularity, climate, resources, and community composition.
“...What is needed in a collection of natural history is, that it should be made as accessible and as useful as possible on the one hand to the general public, and on the other to scientific workers... What the public want is easy and unhindered access to such a collection as they can understand and appreciate ; and what the men of science want is similar access to the materials of science. To this end the vast mass of objects of natural history should be divided into two parts, -one open to the public, the other to men of science, every day, and all day long." Tomas Henry Huxley 1877. On the study of biology. American Naturalist, 11: 210-221.
We don’t participate in nearly as many field studies as we would like (but we’re working on remedying this). We are trying to survey the Israeli Herpetofauna and soricofauna (now here’s a term we assume no one has ever used before! shrew fauna) in the field. We also have a fascinating collaborative study (with Panayiotis Pafilis in the University of Athens) where we study the life history of the lizards Podarcis erhardii and Podarcis gaigeae, and the geckos Mediodactylus kotschyi and Hemidactylus turcicus, as well as other lizards and snakes, on various islands in the Aegean Sea, Greece. These small lizards (the lacertids similar to Israeli Phoenicolacerta laevis) often become larger on small islets, but sometimes grow smaller. Podarcis gaigeae get especially large on a speck of rock that different cartographers argue should be called either Mesa Diavates or Exo Diavates – a giant Diavates male can attain a mass of 20 grams, 3 times heavier than a mainland male. We do field work on Skyros and its adjacent islands, and especially, in the Cyclades Archipelago, and sometimes on other Greek islands trying to quantify morphological, life history, physiological endocrinological and behavioural differences between population inhabiting different islands (genetic differences were found to be minimal, but we are looking further into that as well, with Nikos Poulakakis). We also look hard for possible drivers for the observed differences, especially those related to arthropod abundance, vegetation structure, goat and sheep grazing, sea bird nesting and the usual suspects of island biogeography theory (area and isolation). We compare various traits and their variances between islands and to mainland populations. Rachel is studying these lizards in Greece - and the tree gecko (M. kotschyi, interestingly it is not a tree gecko in Greece, but is mostly saxicolous there) in Israel as well. Rachel is managing more PIs than anyone else, being formally co-supervised by Dave Chapple, but collaborating with Panayiotis Pafilis, Eran Gefen, Eran Levinand potentially others I forgot. Simon's project looking at the natural history of little-known Israeli snakes and lizards: Eirenis decemlineata, Ophiomorus latastii, and Micrelaps muelleri) across the Mediterranean biome in Israel. Rachel is studying microhabitat and its effects on Israeli reptiles along a climatic gradient, and Liat studies the biological rhythms in three species of Ptyodactylus geckos which differ in their activity times (with Noga Kronfeld-Schor). David David studies husbandry and conservation of the spadefoot toad Pelobates syriacus (with Sarig Gafni).
"It (ecological equilibrium) has the disadvantage of being untrue. The 'balance of nature' does not exist" C.S. Elton 1930 Animal ecology and evolution" P. 17