GSM Technical talk (in collaboration with the Geology Department, UM and Institute Geology Malaysia): “The Early Evolution and Diversity of the Chondrichthyes (Cartilaginous Fishes - Sharks, Rays, etc)

Event Code : GSMTT 07-26-2017 Venue Name : Geology Department, University of Malaya Host Name : Coordinator Name : Date From : 2017-07-26

Title: "The Early Evolution and Diversity of the Chondrichthyes (Cartilaginous Fishes - Sharks, Rays, etc)"

Speaker: Dr. Gilles Cuny (Professor in Vertebrate Palaeontology, University Claude Bernard Lyon 1, France)

Time : 3:30 pm~ (Tea 3:00 pm~ )

Dr. Cuny is a renowned researcher in the palaeontology of fossil sharks. He is one of the chief organizing members for the 7th International Meeting on Mesozoic fishes to be held in Mahasarakham University, Thailand, in early August ( ).
"It is often said that sharks are “living fossils”, that is, they have not changed much since their emergence in the early Silurian (ca. 430 million years ago). This short review of Palaeozoic chondrichthyans aims at demonstrating that this is not the case and that modern chimaeras, sharks, skates and rays show a disparity and a diversity, which is much more reduced than the one of their Palaeozoic ancestors.
The phylogenetic relationships of the Chondrichthyes with the rest of the jawed vertebrates (Gnathostomata), which accounts for more than 90% of all living vertebrates, is currently in a state of flux, and the relationships of the fossil forms remain sometimes difficult to decipher. This is mostly due to a poor fossil record of articulated specimens, although a consensus phylogeny seems now to emerge.
Finally, the cartilaginous skeleton of the chondrichthyans is not a plesiomorphic(primitive) feature, and sharks do not represent a proxy for plesiomorphic conditions among gnathostomes."