For male Houbara bustards, extravagant sexual displays come with a price: rapid sexual aging. By studying over 1,700 North African Houbara bustards, researchers in France have learned that the birds, by age six, already begin producing smaller ejaculates with a large number of dead and abnormal sperm. The more showy the bustard, the quicker he burns himself out. As lead researcher Brian Preston said in a prepared statement:
This is the bird equivalent of the posers who strut their stuff in bars and nightclubs every weekend. If the bustard is anything to go by, these same guys will be reaching for their toupees sooner than they’d like.
[Read more about these peculiar birds and see a video of one of their seductive dances at the BBC.]
Image courtesy of Frank. Vassen / Flickr
The Japanese white-eye is one of the most
popular airplane models for snails.
The airplane is, arguably, one of the greatest inventions of humankind, shortening travel times and bringing disparate cultures together. But it turns out that we’re not the only ones to take advantage of flying vehicles. Researchers in Japan have now learned that a certain land snail, Tornatellides boeningi, can quickly travel great distances by hitching a ride in the guts of birds.
If you want to impress a female great bustard, going clean-shaven is probably the wrong approach. According to biologist Juan Carlos Alonso and colleagues at the Spanish National Museum of Natural Sciences, the size of a male bustard’s “whiskers and beard” is correlated with its reproductive success.
The great bustard is a beloved but endangered bird found in Spain and other locations scattered across Eurasia. Males of the species are possibly the heaviest flying birds in the world (rivaled only by the male kori bustard), and each sports whisker-like plumage on either side of its beak, along with neck feathers that resemble a beard. They also engage in showy mating displays, strutting about “like a vicar in a tutu,” according to naturalist Chris Packham in this BBC video.
Have you ever wondered why woodpeckers don’t pass out after scrounging a meal from a tree? Their little brains, after all, undergo decelerations of 1200g as they bang their beaks against the wood–over ten times the force needed to give a human a concussion. Now scientists are learning how to harness the woodpecker’s special abilities not to prevent headaches, but to safeguard our gadgets.
Researchers at the University of California, Berkeley, analyzed CT scans and video footage of the golden-fronted woodpecker (Melanerpes aurifons) to design better shock absorbers. They found that woodpeckers have four traits that ease their noggins: fluid between the skull and brain, a beak that is slightly elastic, a section of soft skull bone, and a bone called the hyoid, or lingual bone, which is also somewhat elastic.
The scientists then constructed a woodpecker-inspired shock-absorbing system around a circuit using materials that approximated the bird’s four absorbers. For example, rubber represented the supportive and slightly-elastic nature of the hyoid bone, while aluminum mimicked the brain-skull fluid. With the circuit securely surrounded, they stuffed it inside a bullet and fired the bullet at an aluminum wall using an air gun.
You’d think birds would hush up at the sound of a predator, especially if that predator’s name is the “butcherbird.” But that’s not the style of the male splendid fairy-wren, and it turns out he has a good reason for raising a ruckus when the butcherbird calls: it helps him get a mate.
Researchers studied this wren-butcherbird interaction in Southern Australia by playing iPod bird songs for wild wrens to hear. As the press release reports, the researchers determined the the males were engaging in a form of “vocal hitchhiking”:
“We have shown that females do, in fact, become especially attentive after hearing butcherbird calls,” said Emma Greig, PhD, first author of the study and currently a postdoctoral researcher at Cornell University. “So, it seems that male fairy-wrens may be singing when they know they will have an attentive audience, and, based on the response of females, this strategy may actually work!”
But how do you tell if a bird is paying attention? The scientists calculated attention by whether the female wren looked towards the call and responded with her own song. Female wrens responded overwhelmingly when the researchers played the male wren’s distinctive “Type II” call immediately following the cry of a butcherbird. From the press release:
“The most exciting possibility is that Type II songs have a sexual function, and that females are more easily stimulated by, or receptive to, displays after being alerted by a predator, such that the male’s song is especially attractive,” Greig said.
Their study, published in the journal Behavioral Ecology, should spur research into other bird species–like the white-throated magpie jay and the fairy gerygone–whose males display a similar post-predator call. And birds may not be the only ones who use fear as an aphrodisiac–anyone headed to a horror movie for Friday date night?
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Image: flickr / dicktay2000
The birds fell over Beebe, Arkansas, but no one is sure what killed them. At around 11:30 p.m. the reports started coming in from residents of the central Arkansas town–worried citizens described the birds falling, dead, from the sky. The birds showed signs of physical trauma, Arkansas bird expert Karen Rowe told CNN Radio:
“It’s important to understand that a sick bird can’t fly. So whatever happened to these birds happened very quickly,” Rowe told CNN Radio on Sunday. “Something must have caused these birds to flush out of the trees at night, where they’re normally just roosting and staying in the treetops … and then something got them out of the air and caused their death and then they fell to earth,” Rowe added.
Researchers found new evidence of the importance of make-up while studying Spanish flamenco dancers flamingos. The scientists discovered that the birds augment their signature coloring by applying tints drawn from their own glands–and they use their painted plumage to attract mates.
The hue of the leggy birds’ feathers come primarily from the pigments in their diet, but researcher Juan Amat found that they also secrete the colored pigments, called carotenoids, from their preen glands. Flamingos (and many other birds) press their heads to the preen glands at the base of their tails to pick up feather-protecting oils, which they then spread around their bodies.
The researchers realized that those oils contain pigments, ranging from red to yellow, by keeping an eye on the flamingos’ feathers and behavior: They noticed that the coloring of the birds was brightest during the mating season, and quickly diminished after they found a mate. Amat told BBC News:
“The rubbing is time-consuming,” Dr Amat told BBC News. “And the more frequently the birds practise it, the more coloured they appear. If the birds stop the rubbing, [their] plumage colour fades in a few days because carotenoids[pigments] bleach quickly in the sunlight.”
It can be hard to sleep with a light shining in your window, but for the male blue tit, this night-lighting gives him a sexual advantage. Researchers have found that male tits that live near streetlights wake up and start to sing on average three minutes earlier than the rest of the gang.
These birds are more likely to be chosen as mates because under normal conditions, early risers are the strongest fully grown birds. When adventurous lady-birds go looking for extramarital affairs in the morning light they are attracted to early risers because they assume they are the macho, macho men of the group.
As a result, any male blue tit–even a young and scrawny fellow–that lives within 50 feet of a streetlight gets about twice as much extramarital action, and has more offspring than male tits that live in other parts of the neighborhood.
From an otherwise unattractive male’s point of view, streetlights must be great. But Kempenaers says he doesn’t have data on the consequences for the blue tit population as a whole if artificial light inspires many females to mate with males that they would normally shun.
World of Wings in Cumbernauld claims Scotland’s “largest collection of birds of prey,” including eagles, owls, hawks, and falcons. The center also served home to a Rüppell’s Griffin Vulture named Gandalf–until Gandalf flew away.
David Ritchie, director of the bird center, told the BBC that the bird flew away during one of the center’s daily shows:
“She got caught in the wind and just went higher and higher until she disappeared…. We would warn people not to approach her but to call the police. She has no fear of humans and she could give someone a very severe bite. Her beak is designed to tear flesh apart.”
There are only about 30,000 remaining Rüppell’s Griffins, native to central Africa, and Gandalf has been at the center since 2006 as part of a zoo breeding program. The birds are scavengers, mostly eating dead animals, and can soar to heights of some 30,000 feet.
So it’s majestic–but its power to reach such heights and its 10-foot wingspan make the escaped vulture a “genuine threat” to airplanes and helicopters, according to Ritchie. The National Air Traffic Services has warned pilots of the threat, the BBC reports. Here’s hoping (for Gandalf’s, the Scottish National Air Traffic Services’, and flesh’s sake) that the vulture returns home soon.
For a prehistoric bird with a bigger bite but no flight, check out Ed Yong’s recent “terror birds” post on Not Exactly Rocket Science.
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Given an allotment of two eggs each year, a lady macaroni penguin starts out by laying a smallish bad egg–then she goes on to lay a bigger, good one. If all goes well, the big egg hatches into a baby bird, but the smaller one never does. Why bother laying an egg that never hatches? A new study doesn’t touch that 60-year-old question, but it does hint that the smaller eggs’ sizes might result from the macaroni’s migration.
A group led by bird biologist Glenn T. Crossin has looked at the size of the bad eggs, which can be anywhere from almost the size of a hatching egg to fifty percent smaller. They noted that some ladies laid their eggs immediately after arriving at a penguin colony, while others waited a couple of weeks–and suspected that some of the penguins formed their eggs en route.