The discovery that some ancient fish had fingers at all is new. Scientists believe these fish are a link between fish and amphibians, such as frogs and salamanders. Amphibians are animals that live both on land and in water.
The two Philedelphia scientists, paleontologist Ted Daeschler and biology professor Neil Shubin, found the fossil inside a boulder. But millions of years ago, that area of Pennsylvania was a swampy delta.
The fin is the size of an adult hand and belonged to a fish that was about six feet long. The scientists believe the fish it belonged to lived about 370 million years ago during the Devonian era, also known as the "age of fishes." Despite return trips to the site, the scientists have found no other bones or fossils that belong to the fish.
"This animal could have slithered through swampy waters," Daeschler says. He does not believe it ever used its fingers to walk on land.
Until this discovery, scientists believed that fingers didn't evolve until after fish made the transition to land, about 360 million years ago.
Scholastic News, Senior Edition, 4/20/98