74 posts tagged nature
Being Gay Is Natural: Just Ask Bonobos (Op-Ed)
There are hundreds of examples of non-reproductive sex among animals, from albatrosses to koalas. But none of these examples can make people quite so uncomfortable as bonobos do. Two bonobo females having sex looks very different than two female albatrosses sitting placidly on their nest. Bonobo sex looks human. (via Being Gay Is Natural: Just Ask Bonobos | LiveScience)
Human nose can detect 1 trillion odours
What the the nose knows might as well be limitless, researchers suggest.
The human nose can distinguish at least 1 trillion different odours, a resolution orders of magnitude beyond the previous estimate of just 10,000 scents, researchers report today in Science Scientists who study smell have suspected a higher number for some time, but few studies have attempted to explore the limits of the human nose’s sensory capacity. “It has just been sitting there for somebody to do,” says study co-author Andreas Keller, an olfactory researcher at the Rockefeller University in New York.
..A human nose has around 400 types of scent receptors. When the smell of coffee wafts through a room, for example, specific receptors in the nose detect molecular components of the odour, eliciting a series of neural responses that draw one’s attention to the coffee pot.
These Animals Have the Worst Sex in the World
It is fair to say we belong to a species obsessed by sex. We are among the only species to have sex for fun, not just for reproduction. For some other species, though, sex is far from fun. In fact, as two recent review papers show, it is a war zone, involving penis fencing and love darts. In 1897, the Italian zoologist Constantino Ribaga discovered a strange organ in female bedbugs, halfway up the abdomen. He suggested they used it to produce sound, like cicadas. But something wasn’t right: In the bundle of cells underneath this organ he found large quantities of sperm. How did they get there? At the time, puzzled scientists concluded males must flood females with sperm, and the female digested the excess—as a “nuptial gift”—using this organ. But this theory was tenuous at best. It wasn’t until 1913 that males were observed stabbing females through this organ with a horrifying syringe-like penis, then copulating with the wound. Sperm swim directly to the ovaries through the body cavity. This has been termed “traumatic insemination.” In the first of the two papers, appearing in Biological Reviews, Rolanda Lange and colleagues at the University of Tuebingen in Germany and the University of Sheffield in the United Kingdom show that similar behavior occurs across invertebrates. (via Invertebrate bad sex: Love darts, penis fencing, traumatic insemination, penis stabbing.)
Wellcome image awards 2014: life in extreme close-up - in pictures
Beautiful, strange and occasionally alarming pictures from the shortlist for this year’s Wellcome image awards – which celebrate the very best in science photography and imaging – from an x-ray of a bat to a micrograph of a kidney stone. The exhibition opens on 12 March at three science centres and the Museum of Science and Industry in Manchester (via Wellcome image awards 2014: life in extreme close-up - in pictures | Science | theguardian.com)
Peacocks make fake sex sounds to attract females’ attention, scientists say. The birds are known for shaking their tail feathers but Canadian researchers have revealed a further sexual tactic. Peacocks have a wide vocabulary of calls, and during mating they make a distinctive hoot. Biologists also recorded males making this sound when out of sight of females and suggest such deception could prove rewarding for the birds. (via BBC Nature - Peacocks fake sex sounds to attract females)
Morphing is one way to make aircraft more efficient
Inspiration from nature, along with the complexity made possible in manufacture through methods such as 3D printing, has allowed new ideas to flourish. As Mike Griffin, President of AIAA, stated at SciTech 2014, “Biology is becoming the new basis for technology.” (via Morphing is one way to make aircraft more efficient)
We now have solid evidence that elephants are some of the most intelligent, social and empathic animals around—so how can we justify keeping them in captivity?
A Reassuring Trunk: Evidence of Consolation in Elephants
Asian elephants console others who are in distress with vocalizations and gentle touches, according to a new report published in the journal PeerJ. Anecdotal reports of elephants behaving reassuringly towards each other are common, but this is the first empirical evidence of consolation in elephants. Joshua Plotnik, a lecturer in conservation biology at Mahidol University in Thailand and CEO of Think Elephants International, and Frans de Waal, of Emory University, observed a group of 26 captive Asian elephants at an elephant park in Thailand. These were mostly unrelated elephants who spent most of their social time together under the guidance of their mahouts, or handlers. The researchers observed the group for nearly a year, recording what happened when one of the elephants became distressed. This could be triggered by events such as a dog walking past, a snake in the grass, or the presence of another, unfriendly elephant. Elephants signal distress by pointing their ears forward, sticking their tails out erect, and letting out a low-frequency rumble, trumpet, or roar. (via A Reassuring Trunk: Evidence of Consolation in Elephants - Wired Science)
Magnetic maps guide young salmon from river to sea
How does a young animal find its way to an unfamiliar location hundreds or thousands of kilometres from where it was born? A reasonable idea might be to find an older, experienced migrant and follow. This might work well for caribou or some songbirds, but what about the many marine animals such as tuna, salmon, eels or sea turtles that never even meet their parents? Our experiments published in Current Biology indicate that juvenile Chinook salmon (sometimes called king salmon) make their journey as if they have a GPS, based not on satellite links but the Earth’s magnetic field. This is possible because the Earth’s magnetic field varies predictably across the globe: the intensity of the field increases from the equator to the poles, and the angle at which magnetic field lines intersect the surface of the Earth similarly increases towards the poles. This forms a grid of coordinates that animals capable of sensing it can use to approximate their position. This is different to a compass, in which the magnetic field is used to find or maintain a direction. A compass can help you walk in a straight line, but it won’t tell you where you are. For that a map is needed, and quite conveniently for salmon they seem to come with one pre-installed. (via Magnetic maps guide young salmon from river to sea)