And Your Bird Can Sing: Celine Dion (right) faces off with some sort of antbird in a battle of song. Stranger things have happened in nature.
Courtesy kookr and McflyIer (composite) via FlickrRemember how odd it felt to learn the Rolling Stones' song, I Wanna Be Your Man, was written by the Beatles' Lennon & McCartney? Or that off-putting twinge of “hmmm” you experienced when hunky hipster Tom Jones covered Kiss, a song written and originally performed by Prince (AKA The Artist Formerly Known as Prince, AKA His Glyphship, AKA The Artist, AKA Prince (again))? Or the unsettling angst brought on by Celine Dion screaming through AC/DC’s You Shook Me All Night Long? In each case, it’s not like they were terrible renditions (I’ll leave that judgement to the music critics), but there was just something not quite right about it. They all just seemed so... unnatural.

Well, as it turns out, it may be a more common natural phenomenon than previously thought. At least in the world of birds. And I’m not talking about Roger McGuinn’s band.

Researchers at Oxford have discovered two different species of antbird in South America whistling the same territorial tune to help eliminate mating competition. They’re claiming it’s the first such discovery.

Although the two birds belong to the same family (Thamnophilidae) they are distinct species (Hypocnemis peruviana and Hypocnemis subflava). Genetic tests done by the researchers showed the two species separated from a common ancestor about three millions years ago. This means the territorial song developed before they split off from their common ancestor.

During the study (the results of which appear in the current issue of Evolution) the scientists made recordings of the songs of males of both species listen here and played them back to competitors in their territories. The reaction in each was similar.

"When we played the song of the [rival] species, the resident bird responded as aggressively as it did to its own species," said Dr Joe Tobias, who led the research along with colleague Nathalie Seddon.

Even though the territorial songs remained similar after the split, other characteristics (such as plumage color and mating calls) diverged along very different paths, and probably aid in preventing confrontation and crossbreeding between the two species.

In effect, the territorial songs of these birds are more or less interchangeable in design and function. Given that they last shared a common ancestor more than 3 million years ago, it is almost equivalent to humans and chimpanzees - which diverged around 5 million years ago - using the same language to settle disputes over resources.

– Dr. Joe Tobias in a press release

So, this kind of cross-species convergence - with different types singing the same song - may not be such an unnatural thing. But then again, Britney Spears did do a cover of the Stones’ (I Can’t Get No) Satisfaction.

SOURCES and LINKS
BBC.com story
Ecological Society of America blog
Colleen McLinn and animal communications
Some other interesting songbird behavior

Tags : zoology, songbirds, evolution, divergence, convergence, birdsongs, birds

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Oh my! Researchers in Virginia have found high levels of mercury in local songbirds. The birds live near a contaminated river, but do not eat any fish or other water creatures that might be contaminated. So, how did they get mercury inside of them?

Turns out the birds ate lots of spiders. And spiders are scavengers who’ll eat pretty much anything. Mercury from the environment accumulates in them, and gets passed along to the birds.

The next question is – how do the land-dwelling spiders get water-borne mercury inside of them?

Tags : Mercury, birds, songbirds, Virginia, spiders, pollution, contamination

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