highlights

publications

The anatomical placode in reptile scale morphogenesis indicates shared ancestry among skin appendages in amniotes.

Most mammals, birds, and reptiles are readily recognized by their hairs, feathers, and scales, respectively. However, the lack of fossil intermediate forms between scales and hairs and substantial differences in their morphogenesis and protein composition have fueled the controversy pertaining to their potential common ancestry for decades. Central to this debate is the apparent lack of an "anatomical placode" (that is, a local epidermal thickening characteristic of feathers' and hairs' early morphogenesis) in reptile scale development. Hence, scenarios have been proposed for the independent development of the anatomical placode in birds and mammals and parallel co-option of similar signaling pathways for their morphogenesis. Using histological and molecular techniques on developmental series of crocodiles and snakes, as well as of unique wild-type and EDA (ectodysplasin A)-deficient scaleless mutant lizards, we show for the first time that reptiles, including crocodiles and squamates, develop all the characteristics of an anatomical placode: columnar cells with reduced proliferation rate, as well as canonical spatial expression of placode and underlying dermal molecular markers. These results reveal a new evolutionary scenario where hairs, feathers, and scales of extant species are homologous structures inherited, with modification, from their shared reptilian ancestor's skin appendages already characterized by an anatomical placode and associated signaling molecules.

news

How to color a lizard: from biology to mathematics

Researchers at the University of Geneva (UNIGE), Switzerland, and SIB Swiss Institute of Bioinformatics report in the journal Nature that a southwestern European lizard slowly acquires its intricate adult skin colour by changing the colour of individual skin scales using an esoteric computational system invented in 1948 by another mathematician: John von Neumann.

events

Drugs and Liver Disease: Modulation of Transport Activity of Canalicular ABC Transporters

02.05.2017 12:00, 352 (Sciences II)

Bruno Stieger (University Hospital Zurich).
hosted by: Howard Riezman.

Research

Our department hosts 12 research laboratories gathering close to 200 scientists, engineers and technical staff. Research topics cover a large variety of topics, such as developmental genetics and neurogenetics, regeneration, evo-devo, physics of biology, phylogenetics or anthropology.

more

Education

Teaching life sciences at the University of Geneva is an important duty for all staff scientists. In addition to the bachelor programme, we also propose specific masters and PhD specialisations through various programmes.

more

contact

Department of Genetics and Evolution
4, Boulevard d'Yvoy
1205 Geneva
Switzerland

office: 4002A
T: +41 22 379 67 85

more