I didn’t know about that – that’s actually really interesting, since Carnotaurus actually did have very mobile shoulder joints.
@zeroxz21@alphynix
Having worked with emus, seen them running, and gotten a real good
look at their wings and the underlying anatomy there, I’m confident in saying they are far too limp and
vestigial to be honestly used for anything. They are not stiff at all, rather they’ve actually seen a dramatic reduction in all the associated muscles compared to other rattites, therefore they are unlikely to be strong enough to use as a rudder. The only supporting literature I can find for emus flapping their tiny, useless wings or using them as a rudder is a 1969 book by Eastman that kind of whimsically postulates it as a possibility. Here’s an emu running flat out, note that the wings are back against the body, hidden in the fluff of their chest:
Here’s about as prominent as the wings get, and I can tell you they are very limp. This girl is displaying so she’s puffed her neck fluff up and let her wings hang forward:
The ‘flapping’ is just the wings moving as the animal moves. Emus tend to use their head and neck more than anything to steer, resulting in a lot of hilarious throwing of their head about as they attempt to turn around – usually they have to slow and lean their entire body, it’s an entirely ungraceful affair! The reason the wings persist is that they haven’t been selected against in any way, and have just persisted because they have no negative impact on the fitness of the animal. I’ve got no idea how muscled/rigid Carnotaurus forelimbs are, but emu limbs are most certainly not rudders!
I’m pretty sure you could genetically modify emus to remove the wings and it would make absolutely 0 difference to general emu operation.
Without a link to a specific video I cannot say for 100% sure that what you’re thinking of is the same thing I’m responding to, but it’s probably a courtship dance! Emus are just as extra in their own way as birds of paradise.
According to this paper, “during the courtship, both genders start
strutting and circling; ruffling out their feathers and
cocking their heads in a shy posture. The male starts
a mating dance with slow, snake-like back-and-forth
movements of his head while circling around the
female.“ Wikipedia also describes mating behavior (with citations to a paper on emu behavior that I can’t get free access to) as such:
“When courting, females stride around, pulling their neck back while puffing out their feathers and emitting low, monosyllabic calls that have been compared to drum beats. This calling can occur when males are out of sight or more than 50 metres (160 ft) away. Once the male’s attention has been gained, the female circles her prospective mate at a distance of 10 to 40 metres (30 to 130 ft). As she does this, she looks at him by turning her neck, while at the same time keeping her rump facing towards him. If the male shows interest in the parading female, he will move closer; the female continues the courtship by shuffling further away but continuing to circle him.[40][41]If a male is interested, he will stretch his neck and erect his feathers, then bend over and peck at the ground. He will circle around and sidle up to the female, swaying his body and neck from side to side, and rubbing his breast against his partner’s rump. Often the female will reject his advances with aggression, but if amenable, she signals acceptance by squatting down and raising her rump”
However, the one thing I’m not seeing in these descriptions is the jumping up and down you described. I looked up some videos, and I’m guessing this is representative of what you’re talking about:
I wasn’t sure if this counted as courtship behavior because the vertical leaps also seemed to be coupled with lunges / kicks, but I ran the video past a couple of zookeepers who have worked with emu and they all think it’s probably still a sexy dance.
BettSplendens Tumblr Evac 