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Sperm Whales Adopt a Dolphin.
In what experts say is an unusual case, a group of sperm whales living near the Azores Islands off the coast of Portugal seem to have adopted into their fold a bottlenose dolphin. In this case the bottlenose has a spinal deformity, which has caused it to be essentially ostracized from its own pod. It is difficult to surmise exactly why the whales have taken the dolphin in among their ranks, and experts believe that match is especially odd since bottlenose dolphins are known to harass sperm whale calves.
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Dung Beetles as Astronavigators.
An oftposed question in nature is how animals manage to navigate almost as if they had GPS. In the case of the dung beetle, the conclusion that scientists have drawn is particularly amazing. Dung beetles are known to move in a straight line after they construct their dung ball. They must do so quickly to prevent rivals from stealing it. But how do they calculate a straight line at night? In a first-of-its-kind experiment, scientists put dung beetles inside a planetarium, turned on the stars and discerned that it actually was the glow of the milky way galaxy that the beetles were using as a reference point. Whether or not other insects are guided by our galactic light will be the subject of future experiments.
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Laboratory Mice Reveal Mechanism of Fear.
The fear response is necessary for survival and scientists have long suspected that the amygdala, a small formation deep inside the brain, plays an important role. Now, using laboratory mice that were genetically engineered to produce a light-sensitive protein in the amygdala, they have discovered the exact regions of the amygdala that trigger the fear response. In this case, the mice were not only genetically altered, but were also behaviorally conditioned to respond with fear to a particular stimulus. Behavioral conditioning strengthens the neural connections in the amygdala, which in turn enhances the chemical fear response. Using lasers, the scientists were able to detect the precise portions of the mouse brain that were responding with fear and emitting the light-sensitive protein when the stimulus was triggered. The insights from the experiments might one day assist veterans who suffer from environmentally induced post traumatic stress disorder.
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Ebola Virus May Have Widespread Roots.
The ebola virus is associated with African roots, but a recent study of Asian fruit bats suggests that this may not be historically accurate. Fruit bats captured in Bangladesh were examined and were found to be carrying an ebola virus very similar to the kind that is found in Zaire Africa. The Asian bats do not migrate long distances and have no contact with their cousins in Africa. In addition, there is evidence that other bats from areas as diverse as Spain, China and the Philippines also carry viruses that are related to the African strain of ebola. All of this suggests that bats may have been the ultimate worldwide reservoir for the ebola family of viruses.
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Newly Discovered “Michelangelo” Spider Sculpts Itself.
We know that animals can resort to incredible feats of camouflage to protect themselves from harm, but a newly discovered spider from Peru has a skill that defies imagination. Instead of camouflaging itself, the tiny spider actually constructs from nearby materials a larger more menacing three-dimensional “sculpture” of itself to ward off predators. When scientists first saw the spider artifact, they thought it was a real spider. But they soon realized that hiding nearby was the diminutive architect, and that what they had been fooled by was a verisimilitude of its own construction, complete with eight legs,a head and a thorax.
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Scientists Create a “Frankensparrow” to Learn About Bird Behavior.
Red Orbit reports that Duke University biologists used a dead swamp sparrow in which they installed mechanized wings to test a theory about male bird aggression. Before fighting, swamp sparrows use gestures as well as vocalizations to warn and intimidate their opponent. In swamp sparrows, the robot was able to wave its wings a sign that it was ready to fight an intruder. Once it did so, it was met by similar wingwaving by other swamp sparrows with which it was jousting. The other sparrows also used wingwave behavior against a stationary stuffed sparrow. Sadly, the research team reports that “this experiment could be on hold, however, because Frankensparrow’s motor is burned out and its head was ripped off in an attack.”
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Great White Shark Victimized by the Cookiecutter.
The great white shark, memorialized in popular culture by the movie “Jaws,” may be one of the fiercest and largest predators of the sea, but it is also a victim. At onetenth the size of a great white, the cookiecutter shark sneaks up on many sea creatures, including the great white, and scoops out a plug of flesh just before darting away to safety. The cookiecutter shark has the largest teeth relative to its mass of any shark, and they are located in the bottom jaws so that they can be used as a sort of melon scoop. Cookiecutters live in tropical waters and they are not fussy about where their lunch comes from dolphins, seals, swordfish and even humans will do in a pinch.
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Antarctic Sea Reached by American Team.
As reported several weeks ago, teams of scientists from the United States, Russia and Great Britain were making separate bids to drill below the Antarctic ice and reach fresh water lakes that had never been tested before. The American team made first contact with the under ice sea and it already has good news to report. Initial tests of the water retrieved from the Lake Whillans borehole ice has revealed microscopic evidence of cellular life and a DNA test that is positive. Scientists believe that the water in Whillans lake has not been exposed to the atmosphere for thousands of years. Further testing will reveal what kind of life forms exist in this extreme environment.
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How Do Owls Turn Their Heads 270 Degrees?
If you’ve always wondered how owls can turn their heads like a bobble doll, you’ll enjoy this short video. Apparently, it requires air sacks in the owl’s vertebrae to protect its arteries from damage.
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Felix’s Dirty Little Secret.
The New York Times reports on a new study about the amount of damage domestic cats actually do to wildlife. According to the Smithsonian Conservation Biology Institute and the Fish and Wildlife Service, domestic cats that are allowed outdoors, even parttime, kill an average of 2.4 billion birds and 12.3 billion small mammals every year in the United States. This is two to four times higher than previously appreciated. How to control this problem, however, is controversial. Perhaps the most humane approach is one that involves trapping stray cats, neutering them and then either returning them to where they were captured or finding them indoor adoptive homes.
“The Dirt: This Week in Nature” curated and written by Robert Raciti.