Biology News Net - Biology

Amazing skin gives sharks a push

Thu, 09 Feb 2012 16:04:02 -0500

Streamlined sharks are legendary for their effortless swimming. George Lauder from Harvard University, USA, explains that the fish have long inspired human engineers, but more recently attention has focused on how the fish's remarkable skin boosts swimming. Coated in razor sharp tooth-like scales, called denticles, the skin is thought to behave like the dimples on a golf ball, disturbing the flow of water over the surface to reduce the drag. But something didn't quite sit right with Lauder. 'All of the shark skin studies were done on flat shark skin mimics that were held straight and immovable. But shark skin moves', recalls Lauder. So, when Masters student Johannes Oeffner joined his lab, Lauder suggested that they take a look at the fluid dynamics of shark skin and its analogues to find out how the fish's motion affects fluid flowing over the rough surface. The duo publishes its discovery that shark skin actually generates thrust to give the fish an additional boost in The Journal of Experimental Biology at http://jeb.biologists.org/.

Fruit flies drawn to the sweet smell of youth

Thu, 09 Feb 2012 16:03:56 -0500

Aging takes its toll on sex appeal and now an international team of researchers led by Baylor College of Medicine and the University of Michigan find that in fruit flies, at least, it even diminishes the come-hither effect of the chemicals of love – pheromones.

Ocean warming causes elephant seals to dive deeper

Thu, 09 Feb 2012 16:03:50 -0500

Global warming is having an effect on the dive behaviour and search for food of southern elephant seals. Researchers from the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association cooperating in a joint study with biologists and oceanographers from the Universities of Pretoria and Cape Town have discovered that the seals dive deeper for food when in warmer water. The scientists attribute this behaviour to the migration of prey to greater depths and now wish to check this theory using a new sensor which registers the feeding of the animals below water.

Satellite tracking reveals sea turtle feeding hotspots

Mon, 06 Feb 2012 17:29:17 -0500

Satellite tracking of threatened loggerhead sea turtles has revealed two previously unknown feeding 'hotspots' in the Gulf of Mexico that are providing important habitat for at least three separate populations of the turtles, according to a study published recently in the journal Biological Conservation.

A battle of the vampires, 20 million years ago?

Fri, 03 Feb 2012 20:28:56 -0500

They are tiny, ugly, disease-carrying little blood-suckers that most people have never seen or heard of, but a new discovery in a one-of-a-kind fossil shows that "bat flies" have been doing their noxious business with bats for at least 20 million years.

Study finds southern Indian Ocean humpbacks singing different tunes

Wed, 01 Feb 2012 17:56:16 -0500

A recently published study by the Wildlife Conservation Society and others reveals that humpback whales on both sides of the southern Indian Ocean are singing different tunes, unusual since humpbacks... A recently published study by the Wildlife Conservation Society and others reveals that humpback whales on both sides of the southern Indian Ocean are singing different tunes, unusual since humpbacks in the same ocean basin usually all sing very similar songs.

Capturing an octopus-eye view of the Great Barrier Reef

Fri, 27 Jan 2012 16:39:33 -0500

The camera enables the researchers to see an aspect of light that humans are essentially blind to: polarized light. Though humans aren't sensitive to polarized light, many reef dwelling animals are but this has not always been taken into account in previous studies of reef communities.

Making memories last

Fri, 27 Jan 2012 16:39:30 -0500

Drosophila Orb2 plays an important role in the persistence of memory. Memories in our brains are maintained by connections between neurons called "synapses". But how do these synapses stay strong and keep memories alive for decades? Neuroscientists at the Stowers Institute for Medical Research have discovered a major clue from a study in fruit flies: Hardy, self-copying clusters or oligomers of a synapse protein are an essential ingredient for the formation of long-term memory.

Bonobos' unusual success story

Mon, 23 Jan 2012 17:21:59 -0500

Bonobos groom each other in Lui Kotale, Salonga National Park, Democratic Republic of Congo. Mate competition by males over females is common in many animal species. During mating season male testosterone levels rise, resulting in an increase in aggressive behavior and masculine features. Male bonobos, however, invest much more into friendly relationships with females. Elevated testosterone and aggression levels would collide with this increased tendency towards forming pair-relationships.

Ancient dinosaur nursery -- the oldest nesting site ever found

Mon, 23 Jan 2012 17:21:54 -0500

An excavation at a site in South Africa has unearthed the 190-million-year-old dinosaur nesting site of the prosauropod dinosaur Massospondylus – revealing significant clues about the evolution of complex reproductive behaviour in early dinosaurs.