Excerpt from the book Animals Evolution Avoided. This book describes 40 animals that ought to exist but don’t, because I made them up.
Scargill’s Gannet has been extinct for about three hundred years. Whereas the seabird called the gannet has numerous colonies around the British coast, the numbers of Scargill’s Gannets gradually dwindled away until none were left. Scientists discovered skeletons of this bird embedded in logs and branches – their beaks stuck fast in the wood. It’s assumed that a degenerative eye disorder caused the birds to become short-sighted over thousands of years. Their original diet was thought to consist entirely of moles. The gannet would spot a molehill forming in a field and dive into the middle of the newly dug earth to pluck the mole out of the ground before flying off. Over the centuries, as their eyesight deteriorated, Scargill’s gannets mistook holes in logs for molehills and were unable to extricate themselves from the wood.
An adult Scargill’s Gannet would be roughly two feet high with a sharp beak and light-brown plumage. It’s thought they built their nests in tall trees overlooking grasslands, allowing them to sit on their nests and look for their prey at the same time. Scientists speculate that this apparent lack of exercise might have led to the gannets suffering from various illnesses including the eye disease that caused their demise. They may indeed have suffered from an early form of avian diabetes.
Scientists can only speculate why the gannet species should have two distinct branches, one hunting over the sea and the other over the land. The best explanation is that some gannets mistook windswept grass on the tops of cliffs as the frothing waters of the sea and started diving on the moles that were appearing there, mistaking them for furry fish.