Keeping an eye on evolution

Dec 03, 2007

University of Queensland research has found the “missing link” in the evolution of the eye.

Professor Shaun Collin, from UQ's School of Biomedical Sciences, together with colleagues from the Australian National University and the University of Pennsylvania, have identified animals that have eyes that bridge the evolutionary link between those designed to simply differentiate light from dark to those that possess a camera-like eye.

Professor Collin said his research gathered evidence from multiple branches of biology, in support of a gradual evolution of the eye, and it proposes an explicit scenario to explain how it was that our eye emerged.

“Charles Darwin wasn't able to reconcile the evolution of the eye given its complexities and diversity of eye designs,” Professor Collin said.

“So it was a major surprise for us that we have found what appears to be a clear progression from a simple eye to a complex eye, which occurred over a relatively short period (30 million years) in evolutionary history.”

Professor Collin said the researchers studied a very primitive fish, the hagfish, to discover the missing link.

“This animal diverged from our own line somewhere around 530 million years ago,” he said.

“Hagfish are simple, eel-shaped jawless and ugly animals, that inhabit the oceans at great depth, and that are renowned for the revolting ‘slime' they exude when disturbed.

“They behave as if blind, though they have a primitive eye-like structure beneath an opaque eye-patch on either side of the head. Previously it had widely been thought that the hagfish eye had degenerated from a lamprey-like precursor.

“But our research suggests hagfish did not degenerate from lamprey-like ancestors, but are instead the remnants of an earlier sister group.”

Professor Collin's research with Professor Trevor Lamb from the Australian National University and Professor Ed Pugh from the University of Pennsylvania, was recently published in Nature Reviews Neuroscience.

Source: University of Queensland

Explore further: Experts 'grasping at straws' to save near-extinct rhino

add to favorites email to friend print save as pdf

Related Stories

Image: Colours of Borneo

5 minutes ago

This image from Japan's ALOS satellite was captured over part of southern Borneo, an island in Southeast Asia.

Recommended for you

Warming leads to more run-ins with polar bears

1 hour ago

Word spread quickly: a polar bear, then two, were spotted near this remote Inuit village on the shores of Hudson Bay, about 1,800 kilometers (1,120 miles) north of Montreal.

Japanese scientist resigns over stem cell scandal

2 hours ago

A researcher embroiled in a fabrication scandal that has rocked Japan's scientific establishment said Friday she would resign after failing to reproduce results of what was once billed as a ground-breaking study on ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.