occurrences also had fossils of terrestrial lifeforms), and their morphology made them ill-suited for lifestyles other than wading and foraging terrestrially, though their feet were relatively small, slender, and had pads, not suited for wading either. These researchers instead argued that azhdarchids were similar to storks or ground hornbills, generalists they termed "terrestrial stalkers" that foraged in different kinds of environments for small animals and carrion, supported by their apparent proficiency on the ground and relatively inflexible necks, for example the well-preserved neck of Phosphatodraco providing information about their morphology. Witton and Naish suggested that their more generalist lifestyle could explain the group's resilience compared to other pterosaur lineages, which were not thought to have survived until the late Maastrichtian like the azhdarchids did (pterosaurs went extinct along with the non-bird dinosaurs during the Cretaceous-Paleogene extinction event 66 million years ago). Witton elaborated in a 2013 book that the proportions of azhdarchids would have been consistent with them striding through vegetated areas with their long limbs, and their downturned skull and jaws reaching the ground. Their long, stiffened necks would be an advantage as it would help lowering and raising the head and give it a vantage point when searching for prey, and enable them to grab small animals and fruit. In their 2021 study that reinterpreted Tethydraco as an azhdarchid, and possibly the same as Phosphatodraco, Labita and Martill noted that azhdarchids might have been less terrestrial than suggested by Witton and Naish, since the Moroccan fossils were from marine strata, as was Arambourgiania from the phosphates of Jordan. They noted that no azhdarchids had been found in truly terrestrial strata, and proposed they could instead have been associated with aquatic environments, such as rivers, lakes, marine and off-shore settings. Pterosaurs are generally thought to have gone gradually extinct by decreasing in diversity towards the end of the Cretaceous, but Longrich and colleagues suggested this impression could be a result of the poor fossil records for pterosaurs (the Signor-Lipps Effect). Since they found multiple lineages (Pteranodontidae, Nyctosauridae, and Azhdarchidae, the latter including Phosphatodraco and others) to have co-existed during the late Maastrichtian of Morocco, this is the most diverse pterosaur assemblage known from the Late Cretaceous. Pterosaurs during this time thereby had increased niche-partitioning compared to earlier faunas from the Santonian and Campanian ages, and they were able to outcompete birds in large size based niches, and birds therefore