The Cornell Birds-of-Paradise Project is a great website that contains all kinds of information about the 39 species in this fantastic group. There are videos and information about the sexual dimorphism in plumage and behavior, and other aspects of the birds’ biology, information about their evolutionary history and the people who study them, and general information about evolution and sexual selection—even a video on speciation. It’s a remarkable and informative site: the best place to visit if you want to see what are the most stupendous examples of sexual selection—and I’m referring not just to the male behavior, but to the female choice that drives much of it. It’s a rich resource for those who teach evolution.
Below is a 4½-minute video of the famous Superb Bird of Paradise (Lophorina superba), whose Cornell page is here. I like this video because it’s not just a “gee whiz–look at this!” presentation (you can see Attenborough’s shorter video of this species on a previous post), but one that shows how at least four different groups of feathers have evolved, and conspire, to create the “smiley face” appearance of the displaying male. There are also several evolved changes in male behavior, including jumping around to stay in front of the female and raising his bill to bisect the blue crown feathers.
After an evolutionist has gotten over her amazement, the first question that then arises is, “Why is the male bird doing this?” That is, what, exactly, is the female looking for that makes her not only drive the evolution of this display, but makes some patterns and behaviors more acceptable than others? Good genes? Some pre-existing sensory bias in the female?
In fact we know almost nothing about what drives this genre of “female choice” sexual selection. This means that, for the time being, we can only marvel at it, and at the power of natural selection—of which sexual selection is a subset.
h/t: Taskin
I’ve enjoyed the Cornell site recently after reading into – The Evolution of Beauty: How Darwin’s Forgotten Theory of Mate Choice Shapes the Animal World – and Us, by Richard Prum. He outlines many of these birds from South America. His key research species are the manakins, which are also shown via films from Cornell.
Prum is an ornithologist from Yale University, who’s main thesis is that Darwin’s guess that female choice in sexual selection is an independent evolutionary process which is not adaptive. These crazy looking males are really hurting their chances of passing on genes with their odd assortment of features, but they are forced to accept the loss due to the whims of the females. In some cases he suggests it can drive a species to extinction.
Carl Zimmer describes Prum’s research on the club winged Manakin who’s bones are modified to produce high frequency sound.
http://www.nytimes.com/2005/08/04/health/birds-that-sing-with-their-wings.html
@Rickflick Are you referring to what Prum calls “maladaptive decadence” [too sexy to survive]?
I think you may have missed this post from May, otherwise you’d have mentioned it: https://whyevolutionistrue.wordpress.com/2017/05/08/an-evolutionary-biologist-misrepresents-sexual-selection/
I may have missed that article I’ve just gotten through the first few chapters of his recently published book. I see the post is critical of Prum’s thesis so it looks like I’ll learn something I didn’t know.
Having read the post on Prum, I see the issue is pretty darn complex and way above my pay grade. I’d have to agree with Jerry that Prum is confusing. With my limited understanding of the field, I felt skepticism creeping into the back of my mind reading some of Prum’s passages.
In the comments I see there is significant disagreement among professionals. I intend, at some point, to finish the book.
And of course the ‘tards over at Uncommon Descent [Barry Arrington & Canadian ‘journalist’ Denyse O’Leary have been dining out on Prum’s new NYT article: “Are These Birds Too Sexy to Survive? Natural selection can’t explain this” by RICHARD O. PRUM, May 5, 2017 [author probably not responsible for the headline]
https://uncommondescent.com/evolution/can-sexual-selection-cause-a-decline-in-evolutionary-fitness/
I’m sure they will make hay out of just about any perceived deviation from orthodox Darwinism.
Thanks for the links.
“In fact we know almost nothing about what drives this genre of “female choice” sexual selection.”
Not limited to birds.
Dang, when I first saw that headline, I thought you were gonna treat us to some Charlie Parker. Here’s a link, for anyone else similarly betrayed by their poor reading skills.
@Ken Lovely, mostly. Thank you. I find the bass mixed too far in front throughout, in a lot of jazz from that era & that track is an example. For that reason I prefer the Bird on this version [plus it’s longer!]: https://www.youtube.com/watch?v=nasZ5s8sBV4
Thx, that does sound great.
Great, now even birds use smileys 😐
So this would be a superb berb?
Suburb?
Nah. It’s from the Latin “Superbus” [superior] rather than the Latin “Suburbium” [under/below/lesser city]
No link
just realised your comment 6. is replying in a new thread to “tubby” in comment 5.
Scusi!
Reblogged this on The Logical Place.
I wonder if some of these dude parts aka “ornamentations” did not evolve as a species-specific signal so that the females don’t spend time doing the wrong species-dude. Could human male penises be relatively huge because other pleasure-capable but infertile humanoid males’ penises were small, so penis length and female human beauty preferences coevolve? if I happen to be a human female who aesthetically prefers the larger phalange (even to the detriment of my poor womb), and if the human male can provide that signal, and the no/low-offspring humanoid male cannot, then pressure can be put toward differentiation of the species by ornamentations that one could imagine to be handicapping in some way but still persist because the other dude is similar and ready to oblige?
Or maybe Dr. Prum is correct and the human male phalange is doomed to grow slowly over evolutionary time until it drags behind them when they walk and eventually (and epically I must say) ends the human species. Sorry guys and do invest in crotch support.
I thought this was fairly good and likely definitive, a study on the primate/carnivore baculum that found correlations explaining at least baculum length:
“The ancestral mammal did not have a baculum, but both ancestral primates and carnivores did. No relationship was found between testes mass and baculum length in either primates or carnivores. Intromission duration correlated with baculum presence over the course of primate evolution, and prolonged intromission predicts significantly longer bacula in extant primates and carnivores. Both polygamous and seasonal breeding systems predict significantly longer bacula in primates.”
[ http://rspb.royalsocietypublishing.org/content/283/1844/20161736 ]
Presumably then competition between males drives major parts of the morphology of the primate penis. And since modern humans are mostly monogamous and without seasonal breeding systems we came up [relatively] short. 😉
I felt kinda bad for the poor little guy at the end.