Blue Collar Scientist

The BBC, LiveScience, and others are reporting on the discovery of a new pterosaur found in north-east China. The find also confirms a prediction of evolution. From the BBC story:

“It is very likely that this pterosaur represents a lineage of arboreal creatures that lived and foraged for insects in the gymnosperm forest canopy of north-east China during the Early Cretaceous,” the researchers write in PNAS.

They conclude this from curved bones in the feet, which are similar to those found in perching birds. This pterosaur is also smaller than most others, of a size that makes sense for perching on branches. Cladistics suggest that this pterosaur was close to the ancestors of the giant pterosaurs, including Quetzalcoatlus, which had a 30-foot wingspan. Thus the new fossil is transitional, being in some ways less derived than later specimens but more derived than the pterosaur’s hypothesized concestor.

“It is interesting to see some clear arboreal adaptations in this species,” said [Smithsonian paleontologist Matthew] Carrano, who was not on the research team.

“It confirms a suspicion we had, that pterosaurs were more diverse in their habitats than we knew from the [fossil] record.”

Let’s be a bit more direct here, in the interests of effective science outreach and clear communication. The notion that pterosaurs were more diverse (in their habitats, or in their phenotype - both apply) than the fossil record previously demonstrated is a prediction of evolutionary theory, not merely a suspicion of paleontologists. There are actually two predictions here, both of which are confirmed by this fossil.

1. Evolution predicts that some species will be absent from the (known) fossil record, and that some of them, if they were known, would illuminate the evolutionary development of their lineage. Here we have an example of a fossil which was unknown until recently, and which does just this. Score one for evolution.
2. Evolution makes the more specific prediction that, when you have lots of fossils of lots of species with specialized adaptations - such as pterosaur fossils - that less derived species will exist earlier in the lineage. Not only that, but it says that most of the characteristics that are common to most or all of the more specialized species will be present in the less derived one. Again, from what’s been published, this fossil confirms this prediction.

Seems I’m on a paleontology kick lately. Undoubtedly this is a result of spending so much time in museums over the last month, looking at fossils. Fair warning - there’s at least one more of these in the pipeline. I’ve had some interesting information and photos from the PI of the crayfish fossils I reported on earlier that I’m working up.

Tags: Cretaceous, education, evolution, fossil, outreach, paleontology, pterosaur, science

This entry was posted on Monday, February 11th, 2008 at 2:52 pm and is filed under education and public outreach, evolution, paleo. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.