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Haplocheirus and Gregory S. Paul
The analyses of Haplocheirus that I've read focus on dispelling any vestiges of
the "temporal paradox". It occurred to me, though, that this animal also has
strong implications for Birds Come First or modified BCF hypotheses (like
Gliding Paravians Come First).
Since Haplocheirus is a basal maniraptoran and 160 million years old, and since
it is primitive, primitively big, and has no aerodynamic features, it seems to
constrain the phylogentic node at which there could have been a flying ancestor
for maniraptorans. It seems that the basalmost ancestor that could have been
volant or glissant is above the Alvarezsauridae node. The basalmost
Therizinosauroid, Falcarius, and the basalmost Oviraptorosaurid,
Incisivosaurus, also seem to be primitively big and non - aerodynamic. This
suggests that the most primitive maniraptorans that could glide or fly were
paravians, and we have basal members of each of the three main paravian
lineages to prove that they did, all from the Jurassic or Early Cretaceous.
I wonder if Gregory Paul, who deserves enormous credit for deducing that
advanced maniraptorans seemed to have aerodynamic ancestors, would agree that
what I've suggested here is the most parsimonious conclusion in light of the
exhilarating new evidence from the last two years.