From fins to feet
The fin bone’s connected to the limb bone.
That’s according to findings reported in the April Science
by a team including organismal biology & anatomy chair Neil
Shubin, associate professor Michael Coates, and Ted Daeschler of
Philadelphia’s Academy of Natural Sciences. In layered rocks
along a north-central Pennsylvania roadside, the paleontologists
unearthed a fossil that helps reveal how fish evolved into amphibians.
The two-and-a-half-inch humerus, or arm bone,
appears to link aquatic creatures with land dwellers, sharing characteristics
of both. The team believes the 365-million-year-old fossil—the
oldest known of its kind—enabled fish to prop themselves up
above the water, indicating that arms and legs began developing
in the sea rather than on dry terrain, as previously thought.
With other specimens from the same dig
site garnering attention and only a small portion of the bone exposed
in the late Devonian Period sandstone, the fossil went unnoticed
until 2001, when the Academy’s Fred Mullison got around to
excavating it. The researchers planned to return to the site this
by Kalliopi Monyios