Wings going from locomotive purposes in juveniles to sexual purposes in adults, plausible?
So I thought about how my dragon-like species would get it's wings between the arms and legs and I figured that this would be the evolutionary path for such a creature:
- Hexapodal ancestor ->
- Quadrupedal walk with arms able to grab (so midway between Bipedalism and obligate hexapod) ->
- Evolve bipedalism ->
- Middle set of limbs becomes vestigial to lessen drag, but the bones are still there ->
- Previously vestigial limbs start growing into wings when the creature becomes bipedal (all this time that bipedalism has been a trait, the bipedalism only shows when the creature is older, but before it becomes an adult) ->
- Wings over time get bigger and bigger as they help with locomotion (not necessarily flight, but WAIR (Wing Assisted Incline Running) is definitely plausible) ->
- Creature as of now
And while this occurs, particularly when Bipedalism evolves, their mass increases as they become the top predator in their ecosystem. This both helps and hinders. It helps because they don't need to move their legs as quickly to acheive the same speed and thus less energy is exerted per muscle cell. But it hinders in that after a certain point, the increase in wingspan won't help with locomotion.
So then I was thinking about what other purposes wings could serve besides the obvious locomotion purpose and then, well, I see wings used for sexual displays all the time in birds(Ostriches and Birds of Paradise are just a few birds that use wings as part of a sexual display), so I figured that even though my species is closer to a Lizard than a bird in terms of integument, the wings could serve a similar purpose. But, I figured that juveniles would still use their wings for WAIR and it would only be at a certain age that the wings would serve a sexual purpose.
Is this plausible though? And what is the most likely thing that would increase the chances of attracting a female? Showing off the colors of the wings? If so, would it be possible for the scaly integument of the wings to change colors due to a response to male hormones, maybe even an increase in blood flow to the wings during mating displays to make the colors even more vibrant?