Dinosaur renaissance "reptiles" and birds. Shortly after the 1859 publication of Charles Darwin's "The Origin of Species", British biologist and evolution-defender Thomas Henry Huxley proposed that birds were descendants of dinosaurs. He cited skeletal similarities, particularly among dinosaurs, the "first bird"—"Archaeopteryx"—and modern birds. However, in 1926, Gerhard Heilmann wrote his influential book "The Origin of Birds", in which he dismissed the dinosaur–bird link, based on the dinosaurs' supposed lack of a furcula. Thereafter, the accepted hypothesis was that birds evolved from crocodylomorph and thecodont ancestors, rather than from dinosaurs. This removed dinosaurs from a central role in debates about the origin of
Archaeopteryx common uses of that term. A more thorough analysis was published soon after to test this hypothesis, and failed to arrive at the same result; it found "Archaeopteryx" in its traditional position at the base of Avialae, while "Xiaotingia" was recovered as a basal dromaeosaurid or troodontid. The authors of the follow-up study noted that uncertainties still exist, and that it may not be possible to state confidently whether or not "Archaeopteryx" is a member of Avialae or not, barring new and better specimens of relevant species. Phylogenetic studies conducted by Senter, "et al." (2012) and Turner, Makovicky, and Norell