IGPP Seminar Series

Gogo formation and its significant fauna

by John A. Long
Natural History Museum of Los Angeles

Abstract

380 MILLION YEAR OLD FISHES FROM GOGO what they teach us about evolution of the human body plan Spectacular, well-preserved Devonian fish fossils from the Gogo sites in northern Western Australia provide a rare window into understanding the early evolution of fishes and the major transformation of fishes to the first land animals (tetrapods). The fossils are preserved in perfect 3-dimensional form as they are able to be acid etched from limestones. In some cases the fish contain mineralized soft tissues such as muscle cells, nerve cells, and even umbilical feeding structures. Recent discoveries published as series of 4 papers in the journal Nature (see Long & Trinajstic 2010 for references) indicated the origins of complex sexual reproduction in vertebrates (see Long 2011 for general overview), pushed back the evidence for live birth (viviparity) in vertebrates by some200 million years and demonstrated the first evidence for accessory air-breathing in ancient marine fishes. Other recent Gogo fish discoveries have elucidated the origins and radiations of the first jawed fishes and how teeth first evolved. The Gogo fishes further show how the basic fish bauplan, or body pattern, underwent most of its radical innovations by the end of the Devonian period as advanced lobe-finned fishes first gave rise giving rise to the first four-legged animals (early amphibian tetrapods). After tetrapods appear the rest of vertebrate evolution was simply fine tuning of an existing pattern to arrive at higher land animals such as reptiles and mammals (Long 2010 ).
Tuesday, 05 April 2011
3853 Slichter Hall
Refreshments at 3:45 PM
Lecture at 4:00 PM