Evolutionary Morphology and Palaeobiology of Vertebrates

Research

Our research covers topics in paleobiology, systematics, evolutionary morphology, and comparative developmental biology . We aim at reconstructing the evolution of complex morphological structures such as the vertebrate skeleton and other organ systems.

We are mostly interested in organismal evolutionary change at the phenotypic level, but sometimes also become involved in genetic studies, as when we study molecular markers of early bone development. Most of our work deals with diverse mammalian, reptile and amphibian groups, although occasionally we were involved in studying other animals (for example, when we found interesting fossils in the field).

The methods we use include comparative anatomy, histology and phylogenetic systematics. In our studies we make use of whatever techniques are relevant to document and compare anatomical traits, including dissections, computed tomography, bone histology, enzymatic clearing and double staining of skeletal tissues, immunochemistry, and molecular labelling of gene expression domains. We run a histology lab for comparative developmental studies and collaborate with other labs in projects involving molecular work. In our palaeohistology lab, we investigate the microstructure of skeletal tissues. We also have sophisticated equipment for morphometric studies of embryos and other small objects, such as fossil teeth.

Sánchez and Scheyer

Developmental palaeontology (Sánchez; Scheyer). Evolutionary change of organisms is fundamentally based on modifications to their developmental mechanisms. Research in our lab focuses on the relationship between evolutionary morphological changes in vertebrates and the developmental patterns associated with those changes. We concentrate on the skeleton because this is a fundamental aspect of the anatomy of all vertebrates and is what is most commonly preserved in the fossil record. Bone is a dynamic and living tissue that functions to support and protect our soft tissue as well as to store essential minerals. The structure of bone is linked to physiology and also reveals the past evolutionary history. We study for example: the development of bone microstructure and the timing of bone development.

Neotropical palaeontology (Sánchez; Scheyer). Our work in the northern Neotropics aims at addressing issues on systematics, palaeobiology and biogeography of different groups of organisms (including giant crocodylians, turtles and mammals) based on new discoveries and subsequent descriptions in poorly known areas in which basic geological work is also conducted.

Domestication in vertebrates (Sánchez). Domestication is an experiment in evolution, as selective breeding has produced increased phenotypic disparity not observed in the wild forebears and otherwise generated in geological time. We aim at investigating the developmental bases of domestication, by investigated at the organismal level changes in growth and life history patterns.

Triassic vertebrates (Scheyer, Sánchez). The Palaeontological Institute and Museum houses perhaps the most important collection of reptiles and fishes of the Middle Triassic Unesco World Heritage site of Monte San Giorgio in Ticino. As such this collection serves as a reference for other localities worldwide, and the museum is visited by numerous international scientists each year. We propagate the continued work on the important specimens from Monte San Giorgio by describing the anatomy of the animals, including for example fish-like ichthyosaurs, crushing-toothed placodonts, or the predatory fish Saurichthys. We further focus on the palaeohistological (microstructural) description of bones and teeth to elucidate the palaeobiology and life history of these extinct animals. By studying their skulls with non-invasive CT scans and geometric morphometric tools, we further learn about their sensory capabilities, which show adaptations to the marine environment.

Evolutionary Theory and Human Affairs (Sánchez / Scheyer). This project aims at creating new symposia, museum exhibits, overview publications and original research on subjects pertaining to methods and concepts in evolutionary biology and its relevance in human affairs. This includes the use of phylogenetic methods in the study of historical changes in material culture (e.g. musical instruments), the creation of venues that facilitate interactions across disciplines, and the communication of research results on evolution that connect the discoveries and concepts to the relevance of our understanding of human biological and cultural evolution.

More ongoing projects in the sites of the two PIs:

Sánchez' research

Scheyer's research

Marcelo Sánchez holds a 33 million years old turtle carapace.