Bottlenose Dolphins Name Themselves.
Communication between bottlenose dolphins has been studied for years. There is recent evidence however, that dolphins “name” themselves through unique whistles and also can call others by using the others’ whistle names. The researchers also noticed that the dolphins appeared to have special names for those family members and friends that they were closest to, which they used only in those intimate contexts. Of course, when a dolphin calls out to others, its whistle can carry a long distance: 12 or more miles depending of water conditions.
Predicting Evolution in Bacteria.
For the first time, scientists have been able to compare in real time the genetic mutations in different bacteria populations. Three test populations were given two different food types and after 1,200 generations the populations diverged into subgroups each of which specialized in one or the other of those particular food types. What fascinates scientists, however, is that after sequencing members of all three original populations, it became clear that the same genetic changes were taking place in the same genes in each population at an almost predictably similar pace. In fact, the mutations matched existing mathematical models. As one researcher put it, “This ‘parallelism’ implies that diversification is a deterministic process driven by natural selection.”
Florida’s Great Burmese Python Hunt.
The proliferation of the invasive Burmese python in Florida’s swamps has been a threat to native wildlife. Desperate to stem the growing problem, the Florida Fish and Wildlife Conservation Commission along with other groups embarked on the 2013 Python Challenge. The goal: catch and remove as many Burmese pythons as possible. The competition drew some 1,600 people from 38 states. In the end, 68 pythons were captured. Although that doesn’t sound like a lot, experts point out that the python is an extremely elusive and well camouflaged ambush hunter and is very difficult to locate. The largest captured python was over 11 feet long. Experts believe the problem began when inconsiderate pet owners released Burmese python pets into the wild.
Anti-anxiety Drugs Found in Fish.
Not all of the pharmaceuticals ingested by patients is metabolized. Some medical drugs are excreted without chemical change, enter the water supply and the oceans as waste water and are thereupon ingested by fish. An example is Oxazepam, a widely prescribed antianxiety drug that has been found in fish in the River Fyris in Sweden. Even in low concentrations, fish react to the drug in a way that parallels the way humans do. Their behavior changes and according to sources quoted in
Discovery News, “the Oxazepamexposed fish became braver and less social. They left their schools to look for food on their own, a behavior that can be risky, since school formation is a key defense against being eaten by a predator.” Scientists are concerned about how this pattern is repeating itself with other pharmaceuticals and what the impacts on the ecosystem will result from altered fish behavior.
The World’s Most Sociable Birds Balance Risks of Early Parenthood.
The sociable weaver is a songbird from South Africa’s Kalahari desert that lives in towering communal nests housing hundreds of birds, many related. The birds can live for up to 10 years, an impressively long age for a bird species. They do not migrate and enjoy a stable climate pattern in the desert which, although hot and dry, offers adequate food. What intrigues scientists about the sociable weaver is that the younger birds do not begin raising a family as soon as possible, but rather help out with the communal tasks of caring for the young of others and tending to the massive nest. It turns out that this “community mindedness” makes sense because to sociable weavers the greatest survival danger is losing young chicks to snakes. By putting off parenthood and strengthening their community, the birds rely upon their longevity to give their own eventual offspring the greatest chance of survival.
Why Didn’t the Meerkat Leader Cross the Road?
The Meerkats of South Africa are a wellstudied species, but a new observation has animal behavioral scientists excited. Meerkats live in colonies of about 40 individuals, but only the alpha male and female reproduce the others just help care for their young. Within this unusual social structure scientists have noticed a risk avoidance habit that appears to benefit the alphas. When faced with a dangerous situation, in this case crossing a trafficked road, the alpha female leads the colony up to the road, but then relies upon a meerkat of subordinate rank to cross the road first. This “guinea pig” behavior is thought to confer a derived benefit for each individual by protecting the alpha female upon whose survival the entire colony depends.
Highway Project a Paleontology Boon.
Workers widening a highway in California’s Laguna Canyon area have come across some interesting new fossil finds. Among the finds are four new species of baleen whales that went extinct an estimated 5 million years ago. Unlike today’s baleen whales, these ancestors had teeth. The toothless baleen whales that act as the giant filter feeders of our oceans today have remnants of teeth in their embryonic stages, but the teeth are reabsorbed before birth. Fossils uncovered during roadcut operations are no novelty in California, where it helps to have archeologists and paleontologists onsite for just such an eventuality.
The Filter Beneath Our Feet.
It may seem like a contradiction, but the layers of dirt below our feet are the single most important factor in keeping the water supply clean. With its many layers of varying materials, the earth’s soil is a natural filter that removes dissolved chemicals and suspended particulates from the underground water. Compared to fresh water above ground, there is more fresh water trapped beneath the earth’s surface. Henry Lin, a professor of hydropedology and soil hydrology at Penn State wants to drive that message home because mismanagement of the earth’s underground waters happens through “construction, underground storage and agricultural operations.”
Think You’re Smarter than a Chimp?
There appears to be at least one cognitive niche in which chimpanzees can easily outshine humans. In an experiment to test short-term memory, a random series of 9 numbers is quickly flashed on and off on a computer screen. All six of the subject chimps could recall each digit and its location on the screen a feat which only a rare human individual can achieve. This “think quick” ability is probably a necessary asset in order to avoid danger in the wild and to navigate fast moving situations, such as negotiating tree limbs. Tetsuro Matsuzawa, a researcher at Kyoto University’s Primate Research Institute had to reassure startled scientists and journalists who viewed a video of the experiment, “don’t worry, nobody can do it.”
Dogs Can Visually Recognize Their Own Species.
Even though human dog breeding has created hundreds of very different dog breeds, which vary enormously in size and shape, an experiment with dogs shows that they can recognize and categorize their own species. Researchers showed pet dogs 144 photos of other dog faces of various breeds. Mixed in with these photos were faces of wild animal faces and humans. The dogs distinguished and picked out the other dogs despite the highly different facial appearances of the various breeds.
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“The Dirt: This Week in Nature” curated and written by Robert Raciti.