Taylori et al. 2019 report,
“From a mechanical standpoint, the forced vibrations excited by hindlimb locomotion stimulate the movement of wings, creating a flapping-like motion in response. This shows that the origin of the avian flight stroke should lie in a completely natural process of active locomotion on the ground.” We looked at this so-called ‘solution’ earlier here prior to peer-review.
The problems are:
- Caudipteryx is an oviraptorasaur, not in the line of bird origin.
- Caudipteryx has round, alternately sliding coracoids (like most tetrapods)
- Only elongate, immobile coracoids enable simultaneous wing flapping.
- Tiny Archaeopteryx is the basalmost bird that has elongate, immobile coracoids.
- Archaeopteryx is also the last common ancestor of all flapping birds, including members of the Enantiornithes.
Phylogenetic analysis must precede all other biological testing.
Otherwise, like Taylori et al. you’re wasting your time imagining the genesis of flapping in a non-flapping taxon.
References
Talori YS, Zhao J-S, Liu Y-F, Lu W-X, Li ZH, O’Connor JK 2019. Identification of avian
flapping motion from non-volant winged dinosaurs based on modal effective mass analysis. PLoS Comput Biol 15(5): e1006846. https://doi.org/10.1371/journal.pcbi.1006846
I haven’t bothered to look at this frame-by-frame, but isn’t the “flapping” alternating [like arms in human running] rather than a synchronous thrust as in any precursor to flight?
True. The authors consider it a precursor behavior. It’s not.