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.
This is an extract from the book Animals Evolution Avoided