Giant Pandas Give Us Another Reason to Love Them.
All but irresistible to humans, the giant panda is always a hit at zoos around the world. But whatever it is about the pandas physical nature that resonates so well with humans, their physiology may turn out to be even more endearing. A new extremely powerful antibiotic component in the panda’s blood, called cathelicidin-AM, is being hailed as a new superantibiotic that kills a wide range of bacteria and fungus quickly. The rise of resistant strains of bacteria, especially in hospitals, means that the newly discovered and already synthesized compound could be an even better reason to love and protect the giant panda.
Dolphins Engage in Gift Giving.
Wild dolphins off the coast of Australia’s Tangalooma Island Resort sometimes present humans with what can only be described as “gifts.” Dead fish, eels, tuna and squid are offered to the bathers by these friendly dolphins. Biologists studying the behavior have postulated a couple of possible reasons for the behavior. One is that it is a sort of reciprocation for the food that tourists lavish on the dolphins who frequent the area. Another is that it is an act of compassion by dolphins who perceive humans as too feeble-minded to fish for themselves.
Why Deer Get Caught in the Headlights.
It is by now a well-worn expression but being like a deer caught in the headlights has become an insult of sorts. It implies that deer are stupid, but the real reason that they freeze in a car’s headlights is more complicated. According to Global Animal, deer are “crepuscular,” which means that their sight is optimized for low light. When car headlights shine in their eyes in the nighttime, the result is temporary blindness — similar to turning on the bathroom light in the middle of the night. Not surprisingly, deer excel at detecting motion, but by human standards their eyesight is poor in acuity, the equivalent of being legally blind.
Assigning Blame for Central African Deforestation.
Between 2,000 and 2,500 years ago, the Central African forests underwent a change that left them less densely packed with trees and opened up new areas of the savannah. Scientists had believed that human action, in this case, farming by the Bantu people of the region, was a likely cause. However, this view was recently attacked in an article in Science Daily which posed an alternative suggestion: during the relevant time period, climate change caused a diminution of the forests. In fact, climate specialists trace a reduction in rainfall to a period some 4,000 years ago reduced forest density. In that scenario, the Bantu farmers simply took advantage of a forest clearing already accomplished by nature.
A New Sea Rise Scenario — Colder Climate.
Not many scientists disagree with the predictions of melting sea ice over the rest of the century. However, a new prediction of just how that melted ice will affect climate has an interesting twist. According to James Hansen of NASA’s Goddard Institute for Space Studies, the initial, temporary effect of melting polar ice will be a cooling of the climate and an increase in the number and intensity of storms. Hansen’s prediction is based upon the notion that warming air temperatures will be cooled by the ice it will melt. Since this means that there will be a greater temperature differential between the very warm equatorial waters and the northern oceans that will be cooled by the melting ice, great weather chaos and higher sea levels will be a likely result.
Birdsong—More Than Meets the Ear.
Humans have an emotional reaction to song and music—music intended to frighten us is quite effective in scary movies, while love songs can instill a romantic feeling. It appears from the study of sparrow brains that birds, too, react emotionally to the songs of male birds. In female sparrows primed for breeding, the sound of a male sparrow’s singing caused measurable brain stimulation in brain areas that correspond to areas that demark pleasurable feelings in humans. On the other hand, male birds exposed to the song of other males showed increased activity in the amygdala of the brain, which is the equivalent of an aggressive signal that alerts the listening male bird to the possibility of conflict.
Grackles Rankle Nerves in the Southwest.
A native of Central America, the broad-tailed grackle has made a new home, but not many human friends, in the Southern and Western portions of the United States. Huge flocks of grackles have inundated towns leaving droppings that threaten to spread disease. They have forced residents to resort to methods as severe as cannon fire, firecrackers and laser lights in an effort to scare them away. So far, the birds are winning. In a town in New Mexico, as many as 5,000 grackles were estimated in the trees in the town’s central square leaving two inches of bird droppings in their wake. The grackles seem to be expanding their territory by about 4% a year.
The Search for an Almost Extinct Egg-Laying Mammal.
The long-beaked, egg-laying echidna is one of the oddest mammals native to New Guinea and Australia. It has a single orifice for reproduction, excretion and egg-laying. It is critically endangered and about 10,000 are believed to be left in New Guinea. An article in National Geographic follows the quest by scientist Kristofer Helgen to determine if any of these primitive mammals still remain in Australia.
The Hottest Year Ever Recorded: 2012
New York Times reporter Justin Gillis discusses scientific reaction to the recent finding that 2012 was the hottest year ever recorded in the continental United States. In fact, rather than being just a fraction of a degree above the previous record, as would be expected, last year exceeded all previous records by a full degree Fahrenheit. Worldwide, it now appears that ten of the hottest years ever recorded worldwide occurred within the past 15-year period.
Emerald Cockroach Wasp Employs Advanced Biochemistry.
The loathsome cockroach plays an important role in the lifecycle of the emerald wasp. The wasp, although much smaller than a cockroach, uses a powerful suite of chemical tricks to transform the cockroach into a nursery and food source for its progeny. It all begins when the female emerald wasp selects its cockroach victim, stings it in the abdomen and injects it with a series of paralyzing chemical cocktails. Eventually, the cockroach turns into a compliant zombie who is led off by the wasp. Before laying her eggs on the cockroach, the emerald wasp performs a final chemical feat: it uses powerful antibacterial chemicals on the cockroach to protect its larvae from the various harmful bacteria they will encounter as they eat their way through the cockroach’s still living body.
“The Dirt: This Week in Nature” curated and written by Robert Raciti.