Rotten fish experiment helps create picture of our early ancestors

WASHINGTON - A study of rotting fish has helped scientists create a clearer picture of what our early ancestors would have looked like.

The researchers, from the Department of Geology at the University of Leicester, wanted to examine the decaying process in order to understand the decomposition of soft-body parts in fish.

This in turn will help them reconstruct an image of creatures that existed 500 million years ago.

The researchers studied the way primitive fish, such as hagfishes and lampreys, decompose to gain an impression of our early ancestry.

The team at Leicester (Rob Sansom, Sarah Gabbott and Mark Purnell) explain: “Our earliest fish-like relatives left fossil remains which have the potential to show us how the group to which we belong evolved from worm-like relatives. But there is a major problem - people are familiar with bones, and teeth as fossils but do not perhaps realise that before these inventions our ancestors consisted of entirely soft bodied creatures. Eyes, organs, guts and muscles all decompose very quickly after death, and as any forensic scientist knows recognising rotted anatomy is difficult.

“Fossils from 500 million years ago provide our only direct evidence of how our earliest vertebrate ancestors evolved from the simple worm-like animals”.

The fossils from the early phase of vertebrate evolution are very rare because being completely soft-bodied they normally rotted away completely after death leaving nothing behind. But very occasionally their remains became preserved as fossils giving us a tantalising glimpse of our early vertebrate relatives.

The findings have been published in the journal Proceedings of the Royal Society B. (ANI)