(Press-News.org) Social birds that forgo breeding to help to raise the offspring of other group members are far more likely care for their own close relatives than for more distant kin, a new study has found.
The study, which looked at a highly social species from outback Australia, the chestnut-crowned babbler, also found that these birds work much harder to care for their brothers and sisters than the young of less-related group members.
The findings, published in the journal Proceedings of the Royal Society B, provide new insights into understanding why some individuals cooperate with each other for a common good rather than pursuing their own selfish reproductive agenda.
"Cooperation is a major evolutionary puzzle," says Dr Lucy Browning from the University of New South Wales and the University of Cambridge, who led the study and is a post-doctoral researcher at the UNSW Arid Zone Research Station, at Fowlers Gap, in far-western NSW.
"One idea is that by helping relatives with whom they share DNA, they can pass on their genes indirectly, but testing this idea in birds and mammals has proved surprisingly difficult.
"An alternative theory is that such cooperation is actually selfish because in group-living species like babblers, individuals can increase their own welfare by helping to make their group larger, irrespective of how closely related they are.
"The fact that babblers preferentially help family members makes it seem likely that promoting the success of kin is the reason they cooperate."
Babblers live in groups in which most members help to take care of young chicks in the nest, despite not being the parents themselves. But like any team activity, some individuals do the lion's share of all the work, while others do nothing at all.
"We wanted to get to the bottom of why some 'helpers' were so industrious while others were apparently so lazy," says Dr Browning. "We found that when helpers are caring for their brothers and sisters, they feed them three times more often than when they are unrelated. In other words, they are much more 'helpful' when looking after family."
The study took place between 2006 and 2008, with birds being fitted with tiny radio transponders that were detected each time an individual visited the nest in order to feed the chicks.
INFORMATION:
Helping family is key for social birds
2012-07-13
ELSE PRESS RELEASES FROM THIS DATE:
Period drama! Australian research criticizes Hollywood portrayals of menstruation
2012-07-13
An Australian study has criticized Hollywood's portrayal of menstruation, warning it's misinforming young girls and portraying periods as overly traumatic and humiliating.
Researcher Dr Lauren Rosewarne, from the University's School of Social and Political Sciences, has analyzed hundreds of representations of menstruation in film and television.
"The presentation of menstruation on screen is an overwhelmingly negative one," she said.
The analysis included jokes, plotlines and references from popular TV shows such as The Big Bang Theory, Mad Men, Friends and Grey's ...
New Au. sediba fossils discovered in rock
2012-07-13
VIDEO:
This video shows a reconstructed skull -- revised parts put together with endocast and transparent cranium.
Click here for more information.
South African scientists will share the country's latest fossil discovery with the world using live virtual technology.
Scientists from the Wits Institute for Human Evolution based at the University of the Witwatersrand in Johannesburg will announce the discovery of a large rock containing significant parts of a skeleton of ...
University of Utah physicists invent 'spintronic' LED
2012-07-13
SALT LAKE CITY, July 12, 2012 – University of Utah physicists invented a new "spintronic" organic light-emitting diode or OLED that promises to be brighter, cheaper and more environmentally friendly than the kinds of LEDs now used in television and computer displays, lighting, traffic lights and numerous electronic devices.
"It's a completely different technology," says Z. Valy Vardeny, University of Utah distinguished professor of physics and senior author of a study of the new OLEDs in the July 13, 2012 issue of the journal Science. "These new organic LEDs can be brighter ...
Paisley Caves yield 13,000-year old Western Stemmed points, more human DNA
2012-07-13
EUGENE, Ore. -- (July 12, 2012) -- Archaeological work in Oregon's Paisley Caves has found evidence that Western Stemmed projectile points -- darts or thrusting spearheads -- were present at least 13,200 calendar years ago during or before the Clovis culture in western North America.
In a paper in the July 13 issue of Science, researchers from 13 institutions lay out their findings, which also include substantial new documentation, including "blind-test analysis" by independent labs, that confirms the human DNA pulled earlier from human coprolites (dried feces) and reported ...
Male sex ornaments are fishing lures, literally
2012-07-13
Talk about a bait-and-switch. Male representatives of the tropical fish known as swordtail characins have flag-like sex ornaments that catch mates just like the bait on a fishing rod would. What's more, a study reported online on July 12 in Current Biology, a Cell Press publication, shows just what any good fly-fisherman would know: Lures work best if they mimic the foods that fish most often eat. For some characins in the study, that means males are waving pretend ants around in hopes of getting a bite.
"This is a natural example of a fishing lure designed to maximize ...
Sake, soy sauce, and the taming of the microbes
2012-07-13
We all know that humans have domesticated plants and animals for our sustenance and enjoyment, but we've tamed various microbes as well. Now researchers reporting online on July 12 in Current Biology, a Cell Press publication, show that the mark of that domestication on microbes, and specifically on the mold used for thousands of years to brew sake and soy sauce from rice and soybeans, looks rather unique.
While changes brought by domestication to plants and animals have rested largely on exaggerating physical traits, changes to microbes have occurred instead via extensive ...
In adult humans, brown fat is actually beige
2012-07-13
The calorie-burning and heat-generating brown fat found in full-grown humans is actually not quite brown; it's beige. So says a new study reported on July 12th in the journal Cell, a Cell Press publication, in which researchers fully characterize this promising obesity-fighting tissue in both mice and humans for the first time.
The findings could lead to more specific ways to address the epidemic of obesity and diabetes by giving those beige fat cells a boost, the researchers say.
"We've identified a third type of fat cell," said Bruce Spiegelman of Harvard Medical ...
The challenges facing the vulnerable Antarctic
2012-07-13
A century ago, the South Pole was one of Earth's last frontiers, but now the Antarctic is under threat from human activity.
Led by Monash University's Professor Steven Chown, a multidisciplinary team of experts from around the globe has set out the current and future conservation challenges facing the Antarctic in a Policy Forum article published today in Science.
The team analysed the effectiveness of the existing Antarctic Treaty System for protecting the region, one of the world's largest commons, from the threats of climate change and, as technology improves, increasing ...
Solar system ice: Source of Earth's water
2012-07-13
Washington, DC —Scientists have long believed that comets and, or a type of very primitive meteorite called carbonaceous chondrites were the sources of early Earth's volatile elements—which include hydrogen, nitrogen, and carbon—and possibly organic material, too. Understanding where these volatiles came from is crucial for determining the origins of both water and life on the planet. New research led by Carnegie's Conel Alexander focuses on frozen water that was distributed throughout much of the early Solar System, but probably not in the materials that aggregated to ...
Oregon's Paisley Caves as old as Clovis sites -- but not Clovis
2012-07-13
CORVALLIS, Ore. – A new study of Oregon's Paisley Caves confirms that humans used the site as early as 12,450 radiocarbon years ago, and the projectile points they left behind were of the "Western Stemmed" tradition and not Clovis – which suggests parallel technological development of early inhabitants to the Americas.
The study, published this week in the journal Science, could have a major impact on theories of how the Western Hemisphere was populated. The research was funded by multiple organizations, including the National Science Foundation.
Lead author Dennis ...