Uma explicação criacionista antiga para formas intermediárias, como o arqueoptérix, ou especificamente para ele. Hoje costumam dizer que, como é classificado taxonomicamente como ave, e não em um táxon cujo nome explicite literalmente seu óbvio elo com os terópodes, ele é "uma ave completamente formada", que só calha de ter características de répteis, ou de dinossauros terópodes pequenos, até mais do que de aves.
Mas esse tal de Freeman, em 1897, criou uma outra hipótese para isso, em certos aspectos até mais inteligente. Em vez de negar, fingir que não enxerga o seu caráter intermediário entre os táxons com uma interpretação tapada de taxonomia, ele esse aspecto intermediário, só que dá outra explicação para o que seria indício de parentesco evolutivo: hibridação. Eram híbridos esporádicos, de pequenos dinossauros e aves, sem nunca deixar descendentes férteis, portanto não sendo significativos em termos de evolução.
[W.T. Freeman], a creationist, but of a different sort than today’s religious fundamentalists, he thought that there was a clear succession of organisms over time in which there were distinct species incapable of evolving into something else. As evidence for this, Freeman cited the fact organisms created near-perfect copies of themselves through reproduction. No organism gave birth to a different species, and even when two species interbred—an inappropriate interaction Freeman deemed “perverted”—the hybrid never became established as a new species.
Within this creationist system, Freeman believed he had found an explanation for Archaeopteryx. Recognized by many naturalists as an early bird with reptilian characteristics such as teeth and a long, bony tail, Archaeopteryx was regularly used as evidence that birds had indeed evolved from reptiles. (“Everything has, or has had, a definite purpose in life,” Freeman wrote, “and the archaeopteryx lived its life in order to bring bliss to the soul of the evolutionist.”) But Freeman took a different view. The mish-mash of bird and reptilian characters indicated that Archaeopteryx was nothing more than a sign of ancient indiscretions:
I suggest that in the earlier days there were ill-developed, low-typed, wallowing birds, also some highly developed reptiles. Perverted sexual instinct exists now, why not then, and as a result of this, why has not the archaeopteryx been an anomalous false hybrid that has been incapable, like other mongrels, of reproducing its kind?
http://blogs.smithsonianmag.com/dinosaur/2010/11/30/a-perverted-view-of-bird-evolution/