A fish dubbed a "living fossil" that hasn't changed fundamentally for 400 million years is still able to genetically adapt to its environment, researchers say.

While scientists have confirmed that coelacanths, whose morphology has not significantly changed since the Devonian age, are in fact evolving slowly, genetic studies from specimens from various sites on the east coast of Africa show genetic adaptation to specific geographic regions.

"We have thus been able to show that despite their slow evolutionary rate, coelacanths continue to develop and are potentially also able to adapt to new environmental conditions," Kathrin Lampert, researcher at the Ruhr-University Bochum in Germany, said.

"The image of the coelacanth as a passive relic of bygone times should therefore be put into perspective."

Coelacanths were considered extinct until a live specimen was hauled aboard a fishing boat in 1938. Since then, more than 100 have been found off the coast of East Africa.

There are probably only a few hundred specimens left in the world, researchers said.

"Coelacanths are rare and extremely endangered. Understanding the genetic diversity of these animals could help make preservation schemes against their extinction more effective," Lampert said.