last edit: October 2024
Our interests thus lay at an intersection of Evolutionary Biology, Biogeography, conservation, Macroecology and Zoology (mainly of reptiles, also of mammals, birds and amphibians, but we had and have projects on fish, frogs, and even, though we wil not always admit it, on arthropods)
We are interested in the different ways animal morphology and natural history adapt them 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. Presumably, many of these differences they are evolutionary and adaptive - others however, may be random with respect to selection.
We study natural history, life history, physiology 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.
We mainly study reptiles, and often we expand to cover land vertebrates as a whole, both as models for biodiversity in general and because, well, they are fascinating in their own right!!
We use four main approaches to study the phenomena we are interested in: Macroecological (i.e., large scale and empirical), Museum specimen based, lab based and field-based. We use published data, data we generate in the field, molecular data we obtain from specimens, and natural history, behavioural observations, life history data, and physiological data obtained in the field and in the lab
Macroecology, Macroevolution and Macro-Conservation
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, distribution, life history and reproduction, ecology and island biogeography of reptiles (especially squamates). This often neglected group of terrestrial vertebrates is species rich (it is the largest tetrapod class in terms of species numbers) and highly variable.
Reptiles are beautiful and fascinating animals as everyone who has studied them closely (in the field that is, see below) 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 assessment 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 and Dave Chapple, and the members of our
Global Assessment of Reptile Distributions working-group (GARD),
we examine the distribution of all (terrestrial) reptiles and the factors that affect the distribution and evolution of reptiles. We are trying mapping reptile distribution globally (a work that many of the lab's best alumni, especially Anat Feldman in charge of snakes, Yuval Itescu of tortoises, crocs and the tuatara, and Maria Novosolov taking care of small-island reptiles led successfuly). Our wonderful collaborator, Uri Roll is making the calls that require a responsible-adult. We study diversity patterns and how our knowledge of them may be biased (e.g., Tal Raz's work), as well as other macroecological phenomena (relationships of features such as body size, range size, range position, macropgysiology, taxonomic trends, and trait geography etc.). Nowadays Anna and Yan are assembling datasets that aim to map the morphospace of all squamates and see how these are related to a suit of ecological and life history traits.
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. With anotehr former postdoc, Gabriel Caetano, we looks at new ways to classify and assess extintion risk and threat status of reptiles, both using supervised machine learning methods to assign species with IUCN-like evaluations, and unsupervised methods to acheive a more nuanced view that more readily incorporates future threats, such as those of land-use change and climate change (which Gopal and Reut also study intensively). Nowadays Tao Liang studies multiple dimentions of reptile diversity such as Beta diversity, sexual dimorphism etc.
We are now working on producing better reptile maps (also looking into the best ways of constructing species distribution models - especially for poorly known taxa, together with Nico Dubos and Pasquale Raia), better assessments, and better trait data, to ask multiple questions regarding trait evolution and conservation status, among other things (and there is always room for the prospective student).
We also teamed with Assaf Levy (BioDB), our (formerly) very own Alex Slavenko, and both Uri Roll and Yaron Ziv (Ben Gurion University) to create The Nature Conservation Index (NCI). The NCI is a tool that shows how well countries are protecting their natural environments. Covering 180 countries, The NCI looks at various factors like the number of plants and animals at risk, the size of protected areas, the health of habitats, and the effectiveness of conservation programs.
The Nature Conservation Index uses four key pillars and a framework of 25 performance indicators to provide a detailed, quantitative analysis of biodiversity and sustainability, and helps us to identify what’s working and where improvements are needed. This knowledge helps inform better decisions to protect our planet's biodiversity and natural resources.
Biodiversity, Phylogeny & Taxonomy of reptiles
We aim to help resolve the phylogeny, taxonomy and distribution of reptiles worldwide, and especially in Israel. As Shai curates the National Natural History Collections of terrestrial vertebrates at the Steinhardt Museum of Natural History we are, in a way, responsible for producing and maintaining the list of these animals, that are automatically protected by law, in order to conserve them.
We started, as usual, eith targeted studies (e.g., Guy Sinaiko's MSc. project, which was done in collaboration with Roi Dor, on Platiceps saharicus, Simon Jamison's project on Micrelaps muelleri, and of course Karin Tamar's multiple works on Acanthodactylus, Phoenicolacerta, Rhynchocalamus etc.). Some of the lab's postdocs and former postdocs are actively working on deciphering the diversity of Israeli reptiles using molecular and morphological taxonomy methods. For example Tali and Marco are working on Chalcides sepsoides (and the Amazoniangenus Plica), and Marco studies the taxonomy of multiple reptile taxa including Elaphe and Pseudopus (with Daniel Jablonski), Tropiocolotes geckos, Telescopus snakes and other taxa.
We are taking a different approach to identify taxonomic issues with Roberta Graboski Mendes (in collaboration with Aaron Bauer). Basically we conduct a broad phylogenetic survey of all known Israeli reptile species from across their distribution ranges within the country and couple this with populations ranging from the Sahara and the Sahel to southern Europe and the deserts of Central Asia and the Arabian Peninsula.
The region as a whole, from Algeria, Chad and Lybia in the west, Sudan and S. Sudan, and even further in the south, Lebanon and Syria in the north, and Jordan and Iraq in the east, as well as Israel itself, has a rich reptilian fauna that went mostly unstudied in terms of taxonomy and molecular phylogenetics. We hope to take steps to amend this (and are always happy to collaborate, and train new students in relevant methods). Roberta is already identifying multiple potentially cryptic species across many local lineages, including her favorites: blindsnakes (Letheobia, Myriopholis) but also in other snake (e.g., Eirenis) and lizard (e.g., Ablepharus and with Molly, Phoenicolacerta) taxa
Archaeozoology
We aim to expand our studies into additional taxa, and go deeper in time, to study patterns and processes in archaeozology - and their relevance for current day diversity and conservation issues. For example, Adva studies an extinct tetrapod, a mammal, the water vole - and assesses its Pleistocene and Holocene populations (with Nimrod Marom) as well as the feasibility of its reintroductions. We aim to expand our probing into the biodiversity of Israel's Pleistocene and Holocene mammal fauna, collaborating with Nimrod, Meirav Meiri, and Guy Bar-Oz. With Meirav we also try to extract and sequence DNA from historical museum specimens.
Museology
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 climate change and other anthropogenic influences with Inon Scharf - and as part of the PhD project of Shahar.
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 with Tamar Dayan and Dan Simberloff), especially in relation to insularity, climate, resources, and community composition.
And of course we use museum specimens from the collections of the Steinhardt Museum of Natural History and other institutions, for mapping species distributions and using these for conservation planning (e.g., with Uri Roll and Enav Vidan), studying taxonomy and phylogeny (see above) as well as morphological evolution.
“...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.
Field studies
We are trying to survey the Israeli Herpetofauna in the field. We had for years a fascinating collaborative study (with Panayiotis Pafilis in the University of Athens) where we study the life history, natural history, morphology and ecology 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. We looked 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). Rachel and Yuval led the field studies, worked extremely hard in the field, produced lots of papers, and I am a little embarrassed to write, we found almost no support for either the common theories found in the literature and ecological/evolutionary theory, or for the new theories we tried to develop as we went along. Yuval still has projects in the Greek islands and we hope to join him soon.
Nowadays we mostly go to the field to collect reptiles to bring to the lab - these can either be 1. snakes for Tao's experiments (with Shay Rotics) - Tao studies reptile movement using dataloggers. 2. Obtaining DNA samples for taxonomic studies (Roberta, Marco, Karin, Molly). or 3. Collecting specimens for physiological experiments - with Shahar and Eran Levin (see below).
Reptile physiology
With Eran Levin we study reptile physiology (metabolism, feeding, water loss, organ size, breathing rates, thermal biology etc) - especially under all types of stress (brummation, pregnancy, extreme climate, and unfortunately - even war). Shahar is taking a comparative approach, both macroecological and field and lab based, to study the effects that the diel cycle, thermal behaviour, season (brummating vs. active individuals), and geography, have on reptile metabolism, thermal traits, water loss rates, fatty acid utiization, and organ size (all in the lab of Eran Levin). We capture reptiles in the field in Israel, bring them back to the lab to conduct the experiments, then release them, completely unharmed, back to nature where we found them.
We also started collaborating with Juan Pablo Muñoz Pérez, Gregory Lewbart, and others, in studying the metabolism of Galapagos marine iguanas (Amblyrhinchus cristatus) during El Niño years, to see whether they reduce their metabolism to allow them to survie these events.
"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
Richness of 12,138 reptile species (raw data, polygons and points, non-modelled ranges), August 2024
