My wife and me were watching 3 noisy friar birds taking a bath this afternoon and she asked "why do they have bald heads?". I have no idea so I searched the net but couldn't find any theories. I've heard that vultures have bald heads because feathers would become dirty when they were feeding on a carcass. Also saw a documentary where it said that the bald head and neck on vultures may help them get bacteria out of their system.
I doubt either of those reasons would apply to a nectar/insect feeder. Anyone heard any theories on why friar birds don't have feathers on their heads?
John
Hi Triker,I think in some species of birds the bald head is important in display and courtship behaviour. Some birds can even change the colour very quickly into something bright.Some like the Noisy Friar Bird have bumps, others have wattles. All this is to "impress the other sex"
So I think, it all comes down to courtship! M-L
M-L
I wonder if there is some connection in the friar bird's deep evolutionary past with a carnivorous bird like a vulture. If vultures evolved in Africa & Africa & Australia were once joined then....bingo!
What? Woko, you don't buy my "sex and courtship" theory??
M-L
I tend to shy right away from that sort of thing, Araminta. Only joking.
I nearly included in my post a comment about the possibility that the friar bird's bald head has remained through the eons because it came to be used as a lady/man-attractor. Now I wish I had!
According to wikipedea if that can be believed, DNA results show they are related to such things as pardalotes, scrub wrens and fairy wrens. So probably not related to vultures.
The sex/courtship theory is a good one but I wonder why both sexes would evolve the bald head. Often only one sex goes for the flashy stuff.
I did think of another idea last night. I wonder if it might be an advantage for getting pollen or nectar from flowers? But you would think that would only be a help for large tubular type flowers and I can't really think of any Aussie natives that fit that description.
The DNA proves then, that even beautiful birds like the fairy wrens can have "ugly relatives".
--if you are bold and ugly, you might as well go all the way and impress!-- There is even "gender equality" in the ugliness? M-L (LOL)
Still think it all has to do with sex!
M-L
Clearly, I should never have ventured into vultures.