The number of digits was once thought to have been reduced in amphibians and reptiles independently, but more recent studies suggest that a single reduction occurred, along the tetrapod stem, in the Late Devonian or Early Carboniferous Laurin, M.1998.
The number of digits was once thought to have been reduced in amphibians and reptiles independently. A single reduction occurred in the Late Devonian. This was along the tetrapod stem. A single reduction occurred in Early Carboniferous Laurin, M.1998. This was along the tetrapod stem. More recent studies suggest this.