Azendohsaurus（爱珍多龙） just shed its dinosaur¹ affiliation²（归属，联盟） . A careful new analysis of A. madagaskarensis—this time based on the entire skull³ rather than on just teeth and jaws⁵—aligns（排列） this 230-million-year-old animal with a different and very early branch on the reptile⁶（爬行动物） evolutionary⁷ tree. Many aspects of Azendohsaurus are far more primitive⁸（原始的） than previously⁹ assumed, which in turn means that its plant-eating adaptations, similar to those found some early dinosaurs¹⁰, were developed independently. The new analysis is published in the journal Palaeontology（古生物学） . "Even though this extraordinary ancient reptile looks similar to some plant-eating dinosaurs in some features of the skull and dentition（齿系） , it is in fact only distantly related to dinosaurs," says John J. Flynn, curator（馆长，管理者） in the Division of Paleontology at the American Museum of Natural History. "With more complete material, we re-assessed features like the down-turned jaw⁴ and leaf-shaped teeth found in A. madagaskarensis as convergent¹¹（收敛的，会聚性的） with some herbivorous（食草的） dinosaurs."

The fossil is a member of Archosauromorpha, a group that includes birds and crocodilians（鳄目动物） but not lizards¹², snakes, or turtles. The type specimen¹³ of the genus（类，种） Azendohsaurus was a fragmentary set of teeth and jaws found in 1972 near (and named for) a village in Morocco's Atlas¹⁴ Mountains. The fossils on which the current research paper is based was discovered in the late 1990s in southwestern Madagascar. Named A. madagaskarensis, this specimen was uncovered by a team of U.S. and Malagasy paleontologists in a "red bed" that includes multiple individuals that probably perished（枯萎，灭亡） together. This species was initially¹⁵ published as an early dinosaur in Science over a decade ago, but the completeness of the more recently unearthed¹⁶（发掘出的） and studied fossils has provided the first complete glimpse of what this animal looked like and was related to. A. madagaskarensis was not a dinosaur.

A. madagaskarensis lived during the period of time that dinosaurs, crocodile relatives, mammals, pterosaurs（飞龙目） , turtles, frogs, and lizards were getting their start, and all of the continents were connected as the supercontinent Pangaea. A. madagaskarensis was 2 to 4 meters long and weighed between 20 and 50 kilos (about 44 to110 pounds). A. madagaskarensis was an efficient herbivore—"a veritable（真正的，名副其实的） four-legged weed-whacker," according to Flynn—with teeth modified for slicing vegetation covering not only its jaws, but also the roof of its mouth. Even though early archosaurs were commonly thought to be primarily carnivorous（食肉的） , A. madagaskarensis shows that traits associated with herbivory were much more widespread across archosaur reptiles¹⁷（爬行动物） .

"Now there are many more cases of herbivorous archosaurs," says André Wyss, professor at the University of California, Santa Barbara. "We are rethinking the evolution of diet and feeding strategies, as well as the broader evolution of the group."

"This is the way science works," says Flynn, commenting on the reinterpretation¹⁸ of the fossils. "As we found and analyzed¹⁹ more material, it made us realize that this was a much more primitive animal and the dinosaur-like features were really the product of convergent evolution（趋同进化） ."

Wyss adds, "In many ways Azendohsaurus ends up being a much more fantastic animal than if it simply represented a generic²⁰ early dinosaur."