Spec DinoVember 15: Fallen Angel

Thanks to their efficient quadrupedal launching mechanism, pterosaurs have managed to conquer both terrestrial and aerial niches without needing to sacrifice their ability to fly, unlike birds. Hence, flightless pterosaurs have never evolved-- almost never, that is. On one volcanic archipelago in the Tethys Sea, in the early Jurassic, a single group of pterosaurs did become flightless, and from them evolved a frightful lineage of predators that would put the contemporary theropod dinosaurs to shame. These pterosaurs were dimorphodontids, members of a group of terrestrial pterosaurs that hunted for insects and small reptiles on the ground, but could still fly short distances to escape predators. Having established themselves on an island with no predators or rivals, they quickly asserted themselves as the apex predators, filling the niches that would otherwise be occupied by theropods. The quadrupedal launch mechanism of their ancestors, no longer needed for flight, was repurposed as a hunting aid, allowing these flightless pterosaurs to pounce on prey larger than themselves, which they would then kill with a crushing bite to the neck. With no dinosaurs on these islands, their prey consists mainly of the large, herbivorous crocodilians that live here. The largest of these flightless pterosaurs, pictured here, is Patherapteryx atrocidens, which can grow to the size of a leopard.