Can I also ask about the use of feather wings as turning aids - it's a
compelling idea, but are there any modern examples we can look to?
Living birds appear to occasionally impart a bit of a rolling moment,
using the wings, while running. Without good kinematic data, however,
it is difficult to confirm that this is the case (as opposed to more
simple balancing or pitch control). Examples of relevant taxa include
galliforms, bustards, cranes, and secretary birds. I have mostly seen
it in cranes and galliforms, but it is anecdotal only.