The technique used by animals to search for food hasn't changed in the last 50 million years, according to a University of Southampton study.

Researchers said that fossilised sea urchin tracks from northern Spain mirror a search pattern used by wide range of animals today.

This is the first such evidence of extinct animals employing a similar strategy and explains why several modern animals use the technique.

Researchers said that creatures including sharks, honeybees, albatrosses and penguins hunt for food based on a mathematical pattern of movement called Lévy walk. The random search pattern features many small steps combined with a few longer steps. The walk is the best way for animals to discover food in times of scarcity.

David Sims, Professor of Marine Ecology and lead author of the study, said that searching food in complex landscapes is a common problem faced by all mobile creatures.

"Finding food in a timely fashion can be a matter of life or death for animals - choose the wrong direction to move in often enough and it could be curtains," Sims said in a statement.

Although wide range of modern animals use the pattern to find food, scientists have not able to determine the origin of the pattern.

For the study, researchers examined the fossilised Eocene-era tracks left behind by sea urchins that lived on the deep sea floor around 50 million years ago. The long trails are preserved in rocky cliffs in a region called Zumaia in northern Spain.

"Finding the signature of an optimal behaviour in the fossil record is exceedingly rare and will help to understand how ancient animals survived very harsh conditions associated with the effects of dramatic climate changes," Sims said. "Perhaps it's a case of when the going got tough, the tough really did get going."

The finding is published in the Proceedings of the National Academy of Sciences.

Topics Animals, Food, Sea, Fossil