I am putting together a paper for PNAS with three coauthors on flight dynamics in Microraptor gui. One thing that is becoming increasingly apparent as I combine my various calculations is that Microraptor was probably pretty darn good in the air, overall. It is not known if it had powered flight ability, but even if Microraptor was an unpowered gliding animal, it has an awful sophisticated set of control surfaces (including some that you don't see in modern birds). This was a highly maneuverable little beast.
I will be posting more about Microraptor and other paravians once our paper is out (assuming that all goes well in review). I may also be giving a talk on the subject at SVP, and Justin Hall (who is also on the paper in question) has recently given some talks on the subject at conferences on the West Coast.
I know that this blog is quite new, and readership is obviously still limited (though growing!), but I would like hear what your most pressing questions are regarding early avian (and near-avian) flight. I am hoping to do a relatively sophisticated series on the topic here once the semester wraps up and my teaching obligations are complete for the summer.
I'm most interested to find out if the basal paravian was flighted or if feather-based flight evolved twice within; once (or more) in avialae and once (or more) in deinonychosauria.
ReplyDeleteI agree with Tomozaurus. It would be interesting if Microraptor represented an independent acquisition of flight apart from avialans. Sinornithosaurus, Anchiornis etc. don't look very flight-worthy (though that's also an assumption that should be tested).
ReplyDeleteI've been wondering about the role of the sternum in flight in paravians/early avians. Would powered flight be possible with the unspecialised theropod sternum, or was further development of the sternum a corollary for the transition from gliding to powered flight.
ReplyDeleteGreat questions all around - honestly, the preliminary information I have at the moment has me leaning towards some powered flight for Microraptorans, but I won't argue that strongly (yet). It is tough to test flight ability in some of the other paravians because they are often quite fragmentary, but there are certainly a few that are worth a second look. It should also be noted that flight ability may have differed between juveniles and adults in paravians in unexpected ways - for example, some of the allometric changes during ontogeny suggest that the young animals might have been better flyers in some species.
ReplyDeleteMarko: with regards to the sternum, there is no good cutoff point for powered flight, so it's a tricky problem (but a great one for research!). I will say that some living birds that fly quite well have pectoralis fractions of only 10% or of total body mass.