Fossil sites before Romer’s Gap (375-360 mya.) show a few primitive tetrapods who seem to eventually become extinct. They clearly weren’t the true predecessors of the true ‘land-animal groups’.
Fossil sites after Romer’s Gap (340 mya.) show an early mixture of these land-animals, the oldest recorded representatives of today’s land-animals. These early tetrapods were only known to date back to about 340 mya. The intervening 25 million years or so is famous for providing not one single tetrapod fossil, not even a tooth, from any locality on Earth.
Blue Beach has for many years been the only site where tetrapods in this gap were being found. Recent discoveries in Scotland (see “In the News”) are now helping widen the door to our understanding. Current research into these important Scottish and Blue Beach discoveries are together altering our theories on the very first colonization of land.