John Kress, chief botanist at the National Museum of Natural History, knows plenty about heliconias, having studied the brightly colored "lobster claw" plants for more than two decades in Central and South America. So the 52-year old scientist wasn't sure what to make of reports from amateur plant collecters on teh Caribbean island of St. Lucia tha tthe lobster claw Heliconia bihai was producing two different flowers. (In these plants, the "claw" is called a bract; the small flower hides inside the bract.)
Meanwhile, Ethan Temeles, 46, an Amherst College ornithologist who was studying St. lucia's purple-throated carib hummingbirds, noticed that males weigh more than females, but their bills are shorter than females'. Typically, the larger the bird, the larger the beak. Might the hummingbirds' unusual morphology, Temeles wondered, be linked to the birds' main food source, lobster claw plants?
The scientists met, and in June 2000 the "plant guy" and the "bird guy" (to borrow Kress' terms) hopped a plane to St. Lucia. In the rain forest, they observed, male hummingbirds prefer teh lobster claw species H. caribaea, which has short, straight flowers hidden within red bracts, while females favor the longer, curved flowers of the green-bracted H. bihai. In both cases, bloom and bill match. But, curiously, in parts othte forest where the males' favorite food is absent, the females' flower has evolved a second form: a red-and-green bracted H. bihai with short, straight flowers that attract the male.
"It became immediately apparent that we were seeing a coevolutionary system," Kress says. The birds' bills and the plant's blooms had evolved together. Postulated by Darwin a century and a half ago, coevolutoin has been difficult to prove in nature; Kress and Temeles, whose findings appeared April 25 in Science, are the first to reliably record it among birds and flowers.
Which came first, changes in the beaks or in the flowers? "It happens at the same time," Kress says. This coevolutionary dance between plants and animals "shows we're all one big happy family on planet earth."
Coevolution verified between birds and flower
Moderator: Alyrium Denryle
- DPDarkPrimus
- Emperor's Hand
- Posts: 18399
- Joined: 2002-11-22 11:02pm
- Location: Iowa
- Contact:
Coevolution verified between birds and flower
From the June issue of Smithsonian. I am transcribing it, so any typos are my fault.
Mayabird is my girlfriend
Justice League:BotM:MM:SDnet City Watch:Cybertron's Finest
"Well then, science is bullshit. "
-revprez, with yet another brilliant rebuttal.
Justice League:BotM:MM:SDnet City Watch:Cybertron's Finest
"Well then, science is bullshit. "
-revprez, with yet another brilliant rebuttal.
Doesn't actually sound like coevolution to me (did a long 3rd year project on it): because the plants havfe adapted to the male birds' beaks, but have not prompted a recriprocal change in the birds.
"I fight with love, and I laugh with rage, you gotta live light enough to see the humour and long enough to see some change" - Ani DiFranco, Pick Yer Nose
"Life 's not a song, life isn't bliss, life is just this: it's living." - Spike, Once More with Feeling
"Life 's not a song, life isn't bliss, life is just this: it's living." - Spike, Once More with Feeling
- Admiral Valdemar
- Outside Context Problem
- Posts: 31572
- Joined: 2002-07-04 07:17pm
- Location: UK
Yeah, sounds more like simple adaption on behalf of one species like the bee shaped flowers of a certain plant for mating.innerbrat wrote:Doesn't actually sound like coevolution to me (did a long 3rd year project on it): because the plants havfe adapted to the male birds' beaks, but have not prompted a recriprocal change in the birds.