Birds never cease to astound us with their grace in the air and cheery songs, because they exhibit design at many levels.
Hummingbird tongue is a micro pump (Science Magazine). The scientists who discovered in 2011 that the hummingbird tongue is a nectar trap rather than a capillary tube (see Illustra animation) have taken it one further. The two scientists from the University of Connecticut have found, after filming dozens of hummingbirds for five years, that the tongue is also a micro-pump. The bird collapses the twin tubes as the tongue exits the beak. The tubes spring back into shape inside the nectar pool, drawing the fluid into the tongue. The flaps then close over the nectar, sealing it into the tubes for delivery into the beak. All this happens automatically without need of muscles or nerves. With repeated licks, the hummingbird can pump its tongue 14 times a second for maximum filling. For more information, see Evolution News & Views.
Detecting turbulence (Science Daily): An article about how flying insects navigate in turbulent air says that birds have their own methods. Insects respond to wind directions; birds apparently rely on visual cues, even at night.
Something to crow about: New Caledonian crows show strong evidence of social learning (Science Daily): Here’s more evidence these black birds are smarter than Aesop thought. They can learn things and apparently pass that knowledge on to their offspring and even refine it—a talent once considered a unique human achievement.
Birds circle and stick together to help them fly in dense fog (New Scientist): Sandhill cranes migrate long distances, but in heavy fog sometimes they circle and fly close together, or settle down till better conditions. Other birds, however, are known to navigate at night, using their instrument qualifications:
But if some birds avoid flying in fog, how come many other species are happy to fly at night? Kirsch says that most birds that do so typically set off at sunset, when there is enough light available for them to orient themselves.
And like airplane pilots, night-time flyers don’t rely only on vision. They also navigate using acoustic and magnetic cues, as well as the positions of the stars and moon, says Andrew Farnsworth of Cornell University in Ithaca, New York.
Darwin’s fast-evolving finches use a natural insect repellent (New Scientist): The Galapagos finches that supposedly inspired Darwin have another trick: they have “evolved” behaviors to ward off insect parasites. Even though they arrived on the islands two to five million years ago in the evolutionary timeline, they just learned this behavior recently, since humans brought invasive species.
Study of birds’ sense of smell reveals important clues for behavior, adaptation (Science Daily): The remarkable way the sense of smell works—at least for fish—is animated in Illustra’s new film Living Waters. The same basic principles work for other vertebrates, including birds and humans. This article discusses differences in olfactory receptors between different species of birds. Each species appears to have receptors tuned to its dietary needs.
Songbirds make mysterious altitude changes during nighttime migratory flights (PhysOrg): Geolocators have shown that some songbirds, like Swainson’s thrush, make sudden altitude changes during flight. The scientists are trying to figure out the reasons for the surprising data.
The bird that flies 16,000 km across the Pacific for no reason (New Scientist): Canadian scientists can’t figure out why the ancient murrelet crosses the entire North Pacific and back again. The feeding grounds and breeding circumstances are similar in western Canada and in Korea or Japan where they land. Maybe it’s just fun.
Researchers find way for eagles and wind turbines to coexist (PhysOrg): We end with a sad story. It’s not clear the title delivers on its promise of co-existence. One thing is clear: right now, magnificent golden eagles are being slaughtered at alarming rates:
An estimated 75 to 110 golden eagles die at a wind-power generation operation in Altamont, California each year. This figure represents about one eagle for every 8 megawatts of energy produced.
And that’s just at one wind farm. What would happen to coal and oil producers if they wiped out this many eagles every year? The usual environmentalist groups don’t seem to be saying much. It’s time for ordinary citizens need to speak up. Another article on PhysOrg describes the migratory habits of eastern golden eagles, another species endangered by wind farms. “Golden Eagles are a priority species for conservation,” the article says, without any recommendations of how they can be protected from spinning blades.
To appreciate eagles more, watch a viral video from the BBC on YouTube of an Imperial Eagle flying unerringly from the world’s tallest structure in Dubai to its trainer’s arm. Two and a half million views and counting!
Can you imagine the horror if the Dubai eagle flew straight into a wind turbine and died on live TV? It would launch an outrage comparable to that for Cecil the Lion. Yet hundreds of these magnificent birds die because of so-called “renewable energy.” Well, the birds beg to differ about that term! We need to speak up for them.
Becoming a bird watcher is a good way to develop your skills of observation. Look for more than the often gorgeous colors and feather patterns. Understand what’s under the hood by watching Illustra’s magnificent documentary, Flight: The Genius of Birds.