Cambrian Deep-Sea Arthropods Had Complex Compound Eyes | Paleontology - Sci-News.com

A team of paleontologists from Australia and the United Kingdom has found that ancient deep-sea creatures called radiodonts developed sophisticated eyes over 500 million years ago (Cambrian period), with some specially adapted to the dim light of deep water.

It now seems likely that some lived at depths down to 1,000 m (3,281 feet) and had developed large, complex eyes to compensate for the lack of light in this extreme environment.

“The Emu Bay Shale is the only place in the world that preserves eyes with lenses of Cambrian radiodonts,” said Dr.

“The more than thirty specimens of eyes we now have, has shed new light on the ecology, behavior and evolution of these, the largest animals alive 500 million years ago.”.

“We discovered much larger specimens of these eyes of up to 4 cm (1.6 inches) in diameter that possess a distinctive ‘acute zone,’ which is a region of enlarged lenses in the center of the eye’s surface that enhances light capture and resolution,” Professor Paterson said.

The large lenses of ‘Anomalocaris’ briggsi suggest that it could see in very dim light at depth, similar to amphipod crustaceans, a type of prawn-like creature that exists today.

The lenses formed at the margin of the eyes, growing bigger and increasing in numbers in large specimens — just as in many living arthropods.