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(Bio) Animal Behavior: Even Microbes Favor Their Own Kin
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PostPosted: Thu Aug 24, 2006 10:35 am    Post subject: (Bio) Animal Behavior: Even Microbes Favor Their Own Kin Reply with quote






Rice University

Tight-knit family: Even microbes favor their own kin
Single-celled microbes close ranks with relatives in times of need


HOUSTON, Aug. 23, 2006 -- New research published by Rice University biologists in this week's issue of Nature finds that even the simplest of social creatures – single-celled amoebae – have the ability not only to recognize their own family members but also to selectively discriminate in favor of them.

The study provides further proof of the surprisingly sophisticated social behavior of microbes, which have been shown to exhibit levels of cooperation more typically associated with animals.

"By recognizing kin, a social microbe can direct altruistic behavior towards its relatives," said postdoctoral researcher Natasha Mehdiabadi, the lead author of the study.

Recognizing one's own family is a common trait among animals – be they chimpanzees, ground squirrels or paper wasps – and because kin recognition can strongly influence cooperative behaviors it can also significantly impact the social evolution of species.

While scientists have repeatedly documented cases of kin recognition, the Rice study is among the first to document the more sophisticated trait of kin discrimination in a social microorganism.

The new study is based on an examination of single-celled Dictyostelium purpureum, a common soil microbe that feeds on bacteria. In the wild, when food runs short, D. purpureum aggregate together by the thousands, forming first into long narrow slugs and then into hair-like fruiting bodies. Resembling miniature mushrooms, these fruiting bodies consist of both a freestanding stalk and the spores that sit atop it. Ultimately, the spores are carried away, usually on the legs of passing creatures, to start the life cycle all over again. But in order to disperse the spores, some of the colony's individuals must altruistically sacrifice themselves in order to make the stalk.

Mehdiabadi and others in the lab of Rice evolutionary biologists Joan Strassmann and David Queller sought to find out whether D. purpureum discriminate by preferentially directing this altruism toward their relatives.

The team collected wild strains of D. purpureum from the Houston Arboretum and took them back to the lab where they were cultured in dishes. In each of 14 experiments, a pair of strains were placed in a dish in equal proportion, and one of the strains in each pair was labeled with a fluorescent dye.

Food was withheld, causing the microbes in each dish to form dozens of slugs and fruiting bodies. Upon observing their social development, the team found that individual fruiting bodies contained predominantly one strain or the other.

"Our experiments ruled out potential differences in developmental timing and showed that these organisms preferentially associate with their own kin," said Strassmann, the Harry C. and Olga K. Wiess Professor in Natural Sciences, who also chairs Rice's Department of Ecology and Evolutionary Biology.

It's unclear how D. purpureum distinguishes relatives from non-relatives, but Mehdiabadi said the process likely relies on a genetic mechanism.

###
Co-authors of the study include, Gad Shaulsky, associate professor of molecular and human genetics at Baylor College of Medicine; Rice technicians Chandra Jack and Tiffany Talley Farnham; Rice graduate student Sara Kalla; and former Rice graduate student Thomas Platt, who's currently at Indiana University.

The research was supported by the National Science Foundation and the W.M. Keck Foundation.

*************************************************************

Questions to explore further this topic:

An Online Introduction to the Biology of Plants and Animals

http://faculty.fmcc.suny.edu/m.....te_map.htm

Exercises in Animal behavior

http://asab.icapb.ed.ac.uk/exercises/ks2/
http://asab.icapb.ed.ac.uk/exercises/gcse/
http://asab.icapb.ed.ac.uk/exercises/alevel/
http://asab.icapb.ed.ac.uk/exercises/alevel_psych/
http://asab.icapb.ed.ac.uk/res.....rce_packs/
http://asab.icapb.ed.ac.uk/practicals/
http://asab.icapb.ed.ac.uk/resources/cameos/
http://www.accessexcellence.or.....avior.html

Profiles of scientists who study animal behavior

http://asab.icapb.ed.ac.uk/resources/profiles/

Animal Communication

http://animalbehaviour.net/KidsPages/KidsStuff.htm
http://www.sciencenetlinks.com.....;DocID=388

Genes, Behavior, and the Social Environment:
Moving Beyond the Nature/Nurture Debate


http://www.nap.edu/catalog/11693.html

Animal behavior (African Safari Holidays)

http://www.wildlifeafrica.co.z.....avior.html
http://asci.uvm.edu/course/asci001/behavior.html

History of Animal Behavior Biology

http://salmon.psy.plym.ac.uk/year1/animbeha.htm

What is animal behavior research?

http://www.animalbehavior.org/.....avior.html

A course on animal behavior

http://instruct.westvalley.edu.....6page.html

What are animal cummunities?

http://www.ac.wwu.edu/~stephan/Book/chap11/11.html

Mammalian social systems

http://www.bio.davidson.edu/pe.....sHome.html

Avian social systems

http://www.bio.davidson.edu/pe.....stems.html

What is animal cognition?

http://www.sciencemag.org/cgi/...../5781/1734
http://www.univie.ac.at/zoolog.....esLearning

Amazing Animals

http://www.bbc.co.uk/nature/reallywild/amazing/

Special Topics

Social Biology of Ants
http://arjournals.annualreview.....163.002021

Social Biology of Bees
http://www.scieng.flinders.edu.....chwarz.htm

Social Biology of Wasps
http://es.rice.edu/projects/Bi......home.html

GAMES

http://www.nationalgeographic......maina.html
http://www.hamsterdance.com/funhome.html
http://www.bbc.co.uk/nature/reallywild/fun/


Last edited by adedios on Sat Jan 27, 2007 3:35 pm; edited 2 times in total
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PostPosted: Thu Aug 24, 2006 11:33 pm    Post subject: Reply with quote

Prof Angel,
Very very interesting! Now I understand the words of Pres G.W. Bush when he said: "We take care of our own!"
Ciao,
KaNoel
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PostPosted: Fri Sep 29, 2006 5:44 pm    Post subject: The Secret Lives of Wild Animals Reply with quote

27-Sep-2006

The Secret Lives of Wild Animals

A new interactive web site from the U.S. National Science Foundation features movies, researcher interviews and animal facts from several animal tracking technology projects.

http://nsf.gov/news/special_re...../intro.jsp
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PostPosted: Mon Oct 30, 2006 8:00 pm    Post subject: Why Play Dead? Reply with quote

Why Play Dead?
Rethinking what used to be obvious
Susan Milius

Gary Gerald studies animal movement, so when two female brown snakes in the lab had babies, he wanted to see them in motion. He watched them crawling on a solid surface, then moved the youngsters to water in a modified gutter. But the system didn't work as planned for the newborn snakes.

"I would pick the little guys up and drop them right in the water, and right when I dropped them, they flipped upside down. They stayed motionless. Their bodies were rigid so if you touched one part, they'd spin like if you touch a stick floating on the water," says Gerald. He concluded that this was a new example of an animal feigning death.

For the full article:

http://sciencenews.org/articles/20061028/bob8.asp
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PostPosted: Fri Dec 01, 2006 11:04 pm    Post subject: Invasive Ants Territorial Reply with quote

Invasive Ants Territorial
When Neighbors Are Not Kin


November 30, 2006

By Sherry Seethaler

A study led by UC San Diego biologists shows that invasive Argentine ants appear to use genetic differences to distinguish friend from foe, a finding that helps to explain why these ants form enormous colonies in California.

In the December issue of the journal Molecular Ecology, the biologists provide the first data on territorial interactions among Argentine ants in the field. In California, Argentine ants form expansive “supercolonies” containing millions of nests and stretching hundreds of miles. Researchers have disagreed on the reason for the lack of aggression between ants from different nests in the same colony.

“Some ecologists have hypothesized that environmental factors act to reduce aggression among Argentine ants in California,” said David Holway, an assistant professor of biology at UCSD and senior author on the study. “However, we found that while ants from the same supercolony do not fight, clashes between ants from different supercolonies occur commonly along territorial borders.”

For the full article:

http://ucsdnews.ucsd.edu/newsr.....ntcolo.asp
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PostPosted: Fri Feb 02, 2007 8:04 am    Post subject: Deadly Superbugs are Talking About You Reply with quote

Deadly Superbugs are Talking About You

By Maria Cheng
Associated Press
posted: 01 February 2007
02:28 pm ET

LONDON (AP) — Do germs communicate? Many scientists think so and are betting the chatter may hold the key to developing the next generation of drugs to fight killer superbugs.

The conventional wisdom has long been that the carpet-bombing approach is the best way to fight infection. But as evidence of bacterial bonding has mounted in the past decade, researchers are now focusing on antibiotics that will break down the lines of communication.

In the last 20 years, the number of scientists working in this field has jumped from a few solitary researchers to thousands. In Britain, the strategy is one of the top research priorities of a newly formed center dedicated to stopping superbugs.

For the full article:

http://www.livescience.com/hum.....ation.html
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PostPosted: Fri Mar 16, 2007 7:27 am    Post subject: The Mongoose: Nasty to Neighbors, Friendly to Strangers Reply with quote

The Mongoose: Nasty to Neighbors, Friendly to Strangers

By Jeanna Bryner
LiveScience Staff Writer
posted: 15 March 2007
09:08 am ET

Takeovers are the norm and boundaries are marked with feces, urine and anal secretions in a mongoose's world, so there's no such thing as a friendly neighbor.

Mongooses, small cat-like carnivores, engage in brutal battles with neighbors. But a new study finds the animals are nowhere near as defensive with strangers.

Researchers captured video of the social animals as they sniff out enemies and send out alarm calls, showing that banded mongooses (Mungos mungo) aggressively defend against neighbors while allowing absolute strangers to cross right into their territories.

For the full article:

http://www.livescience.com/ani.....hbors.html
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PostPosted: Wed May 30, 2007 1:40 pm    Post subject: Evolution of animal personalities Reply with quote

Santa Fe Institute
30 May 2007

Evolution of animal personalities

Scientists provide an explanation
Animals differ strikingly in character and temperament. Yet only recently has it become evident that personalities are a widespread phenomenon in the animal kingdom. Animals as diverse as spiders, mice and squids appear to have personalities. Personality differences have been described in more than 60 species, including primates, rodents, birds, fish, insects and mollusks. New work by Max Wolf (University of Groningen; currently at the Santa Fe Institute), Santa Fe Institute Postdoctoral Fellow Sander van Doorn, Franz Weissing (University of Groningen), and Olof Leimar (Stockholm University) offers an explanation for the evolution of animal personalities. Their findings are detailed in “Life-history trade-offs favour the evolution of animal personalities” in the May 31 issue of Nature.

The evolutionary origins of “animal personality”—defined as consistent behavior over time and in different situations—is poorly understood. Why do different personality types exist within a single population given that, at first sight, one would expect one type to be more successful than another" Why are individuals not more flexible considering that personality rigidity sometimes leads to seemingly inefficient behavior" Why do we find the same types of traits correlated with each other in very different kinds of animals"

The authors argue that in many cases personalities are shaped by a simple underlying principle: the more an individual stands to lose (in terms of future reproduction) the more cautiously it is likely to behave, in all kinds of situations and consistently over time.

They begin with two basic observations. First, variation in personalities is often structured according to differences in the overall willingness to take risks. Second, individuals are often confronted with a trade-off between current and future reproduction: the more an individual currently invests in reproduction, the less resources are left to invest in future opportunities, and vice versa. Using a mathematical model the authors demonstrate that this fundamental trade-off can give rise to populations where some individuals put more emphasis on future reproduction than others. Individuals who invest in future reproductive success evolve to be consistently risk-averse in different behavioral contexts (e.g. encounters with predators and aggressive interactions), whereas individuals who put emphasis on current reproductive success evolve a more risk-prone personality.

The researchers intend to continue their collaborative work on the evolution of animal personalities. Currently, at the Santa Fe Institute, Max Wolf and Sander van Doorn are developing alternative ideas on structuring properties of personalities.

###
The Santa Fe Institute (SFI) is an acknowledged leader in multidisciplinary scientific research. It’s objectives are to discover and understand the common fundamental principles in physical, computational, biological, and social complex systems that underlie many of the most profound issues facing science and society today. By transcending disciplines, breaking academic molds and drawing together an international network of unorthodox creative thinkers, SFI is an independent non-profit research and education center supported by grants, charitable giving, and corporate relationships.
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PostPosted: Tue Jun 12, 2007 9:31 am    Post subject: Undergraduate research shows leaderless honeybee organizing Reply with quote

University of North Carolina at Charlotte
11 June 2007

Undergraduate research shows leaderless honeybee organizing

Undergraduate education generally involves acquiring “received knowledge” – in other words, absorbing the past discoveries of scholars and scientists. But University of North Carolina at Charlotte senior biology major Andrew Pierce went beyond the textbooks and uncovered something previously unknown.

Pierce’s discovery has to do with detecting a significant new detail concerning the behavior of the European honeybee – perhaps the most studied and economically important insect on Earth. Beyond agriculture, the finding may also have key implications for understanding the dynamics of all social animals, including man.

Pierce’s recently reported his research in an article appearing in the behavioral biology research journal Ethology, with co-authors Lee Lewis and UNC Charlotte biology professor Stanley Schneider, Pierce’s mentor. Pierce was first author on the paper – a rare achievement for an undergraduate.

“It was a very good work and an impressive achievement for a student researcher – he got a publication as an undergraduate,” Schneider noted. “I really like working with our undergraduate honors students – they are so bright.”

Pierce, age 22, has been working as a researcher in Schneider’s lab for the past two years through a UNC Charlotte Honors College program that fosters research experiences for undergraduates.

Using an ingeniously designed experiment, Pierce and his co-authors were able to document details of bee social behavior that fundamentally confirm the hypothesis that major colony activities are initiated by the cumulative group actions of the colony’s older workers, not by the queen’s individual decision.

What Pierce and colleagues found was that older workers gave signals to the queen and to the rest of the colony that it was time to swarm and leave the hive. Later, they were able to observe inside the swarm itself and see workers give the queen a signal, known as “piping” that tells her to fly.

“Researchers have never reported worker piping being done on the queen before, so some of what we found was exciting,” Pierce said. “It was generally surprising to see the level of interaction that the older bees have with the queen. This doesn’t normally happen in the hive,” he noted.

“It’s interesting because it shows that though the queen has a tremendous impact on the colony, she’s not the decision maker,” Schnieder said. “The colony is not a dominance hierarchy and, from a human perspective, this is unusual. Our human society is very dominance hierarchy structured --we have centralized systems of control. But bee colony systems of control are very different – they are totally de-centralized.”

Schneider’s lab studies the honeybee and its behavioral ecology. Like humans, honeybees are remarkable for living in large organized groups where highly developed social behaviors coordinate the efforts of thousands of individuals to accomplish complex tasks – manufacturing, community defense, environmental control and maintenance, food production, brood-rearing and education. Like human civilizations, bee societies follow organizational principles, such as following social rules (like human customs and laws) and division of labor.

But here the similarity ends. Bees do not have large brains and are not capable of complex thought like humans. Though the bee colony is centered around the queen and her reproductive capabilities, findings by Schneider and others indicates that she does not exactly “rule.” Instead, the colony appears to be controlled by the anonymous consensus of the colony’s workers.

Though it is of great interest to researchers studying social behavior, a great mystery still remains regarding how bee societies effectively direct and coordinate complex operations without a central controlling intelligence. Pierce’s finding is part of an ongoing research effort in Schneider’s lab aimed at understanding the mechanisms of leaderless societal management – in particular, the importance of two communication-related behaviors known as the “vibration signal” and “worker piping.”

Different from the famous “waggle dance” that foraging worker bees perform to tell other bees where to find a food source, the vibration signal appears to be a more general, multi-purpose form of communication. Schneider has concluded that this signal, which consists of one bee grabbing another bee (worker or queen) and then vibrating its body, does not convey a specific message, but instead is a form of “modulatory communication” that alters existing bee behaviors (making bees perform their jobs more actively, perhaps) or changes bees response to other signals.

Pierce and Schneider have documented in their current paper how workers use the vibration signal to prepare the queen for swarming by making intrusions into her “court” and vibrating her hundreds of times an hour. She responds by changing her behavior -- reducing her food intake, slowing egg laying and becoming more active. At this point, the workers begin to send a second signal that researchers call “worker piping” at a fevered pitch. Piping, which consists of bees making contact and vibrating their wing muscles rapidly, appears to be a general instruction to fly.

The researchers document that the workers stop using the vibration signal when the queen flies and leaves the nest with the swarm. Piping, however, continues in the swarm, as the bees need to make the queen fly again once a new nest site has been selected.

“Drew Pierce did this project last summer,” Schneider explained. “We constructed a special observation stand where we could actually see how workers were interacting with queens inside a swarm cluster, where they are hanging in a tree. That was really interesting, because nobody had ever really been able to look at that before,” he noted.

“What was interesting was how little attention the workers pay the queen – until it became time to go – to become airborne. Then they started interacting with her at very high rates, and performing the ‘worker piping’ signal on her. This interaction is a behavior that nobody had described before,” Schneider said.

Contrary to the popular conception of a colony controlled by instructions from its breeding queen mother, the research shows a picture of the queen as a passive egg layer whose own behavior is programmed, with changes dictated by signals delivered by older workers.

This does not mean, however, that the colony is controlled by a key group of experienced bees either. The worker bees that deliver the critical signals have short life-spans and tiny brains incapable of managing the colony the way a human village might be managed by a council of elders. Instead, critical strategic choices, such as the assessment that it is time to divide the colony and swarm, appear to be decided by the dynamics of the group itself. Social interactions, environmental pressures or group dynamics in some still-unknown way initiate a string of behaviors that effectively manage complex group activities.

“It is a real challenge to understand how bee colonies work, but it is also fascinating because they are so different. Evolutionarily, they got to the same point as humans – living in these highly organized societies that function with remarkable efficiency -- but they are organized so differently when you start digging into them,” Schneider said. “It’s interesting that these major differences can result in the same emergent social properties. It may tell us something about ourselves.”
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PostPosted: Wed Jun 13, 2007 9:06 am    Post subject: Study investigates 'divorce' among Galapagos seabirds Reply with quote

Wake Forest University
13 June 2007

Study investigates 'divorce' among Galapagos seabirds

Being a devoted husband and father is not enough to keep an avian marriage together for the Nazca booby, a long-lived seabird found in the Galapagos Islands off the coast of Ecuador.

Many Nazca booby females switch mates after successfully raising a chick, according to a Wake Forest University study scheduled for publication in the journal Proceedings of the Royal Society B: Biological Sciences June 13.

This is surprising because there is an advantage to staying together, said Terri Maness, a doctoral student who co-authored the study with David J. Anderson, professor of biology at Wake Forest. The chance of successfully breeding probably improves as the pairs of birds get older and are together longer, as has been found in other birds.

But, often the female seeks a divorce after a few breeding seasons. Since males significantly outnumber females in the colony studied, there are plenty of bachelors available if the female has a wandering eye.

“Our study population has 50 percent more males than females, creating the opportunity for females to trade a current mate, which may be worn-out from recent breeding effort, for a ‘refreshed’ non-breeding male,” Maness said.

It takes a lot of energy to raise a chick and the responsibility is shared by both males and females. They raise one chick at a time. Parents incubate the egg for 43 days. Then, it takes another 100 to 120 days of parental care until the baby bird can fly. The parents will usually continue to provide some meals to the fledgling.

So, if, when mating season rolls around again, a male looks a little ragged from taking care of junior, his mate is likely to choose another. A male’s capacity to raise offspring, a quality that can vary with time, may carry more weight with a mate than stellar genes or past breeding success, Maness said.

She used 14 years of data on about 950 males and 700 females in the study. During that time, the majority of the females in this group gambled on a new mate, sometimes one that had never bred before.

This is one of the few studies that addresses divorce in successfully breeding bird pairs, Maness said. “This study really predicts that the probability of divorce increases with the birds’ success at breeding and raising a chick, because the effort required may tire out the male and consequently his mate may reject him.”

It also shows that males of this species are probably never permanently in or out of the mating game, in contrast to many other animals, she said. A male Nazca booby cast off by a current mate may be selected by a different female the next year, after he has had a chance to regain his condition.
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PostPosted: Wed Jun 20, 2007 9:18 am    Post subject: ESF EUROCORES Programme OMLL helps uncover ancient human beh Reply with quote

20. June 2007 10:38
ESF EUROCORES Programme OMLL helps uncover ancient human behaviour
European Science Foundation

A major question in evolutionary studies today is how early did humans begin to think and behave in ways we would see as fundamentally modern? One index of ‘behavioural modernity’ is in the appearance of objects used purely as decoration or ornaments. Such items are widely regarded as having symbolic rather than practical value. By displaying them on the body as necklaces, pendants or bracelets or attached to clothing this also greatly increased their visual impact. The appearance of ornaments may be linked to a growing sense of self-awareness and identity amongst humans and any symbolic meanings would have been shared by members of the same group.

In Europe, amongst the oldest known symbolic ornaments are perforated animal teeth and shell beads, found in Upper Palaeolithic contexts that date to no more than 40,000 years ago. Such finds are apparently associated with both modern human and late Neanderthal sites. Together with cave paintings and engravings they offer the strongest indications that European societies of those times were capable of thinking in an abstract manner, and symbolising their ideas without relying on obvious links between a meaning and a sign. But, now, a growing body of evidence indicates symbolic material culture consisting of engravings, personal ornaments and systematic use of beads had emerged much earlier in Africa.

In a recently published paper in PNAS (Proceedings of the National Academy of Sciences of America) archaeologists from Morocco, UK, France and Germany, including researchers (M. Vanhaeren and F. d’Errico) funded by the Origin of Man, Language and Languages programme of the European Science Foundation, have been able to show that some of the earliest examples of bead making may date back as far as 82,000 years ago in North Africa. The evidence is in the form of deliberately perforated Nassarius marine shells, some still smeared with red ochre, that were found deeply stratified in archaeological levels in Grotte des Pigeons at Taforalt in northeastern Morocco. Led by Abdeljalil Bouzouggar of Rabat University and Nick Barton of Oxford University, a multidisciplinary team has been working in this massive limestone cave for the past five years. The finds come from a sequence of ashy deposits that have been independently dated by scientists at Oxford and in Australia using four different techniques which allow accurate age estimates for the layers with shells to be made. According to Nick Barton, the singular importance of these discoveries “is that they come from securely dated archaeological contexts and show unequivocally that beadmaking traditions existed in Africa that are twice as old as those in Europe”.

The interpretation of the findings are still regarded as controversial by some who would question any appearance of modern symbolic activity before about 40-50,000 years ago. The archaeological dating evidence from the Moroccan site is however indisputable. At Taforalt, 13 Nassarius gibbosulus shell beads have been recovered in a deeply stratified occupation horizon towards the back of the cave. The finds were all made close together and sealed in lightly cemented ashy lenses (the remains of hearths) combined with abundant evidence of human activity in the form of lithic artefacts and animal bones. Amongst the stone tools associated with the shells are thin, bifacially worked foliate points typical of the Middle Palaeolithic Aterian technology, and probably used as spear heads. The bones of wild horse and African hare, found with them, represent human food residues.

Preservation of environmental evidence at Taforalt is also exceptionally good and reveals that at the time of the ‘bead occupation’ the landscape was dry, open and sparsely vegetated with some locally wooded habitat. This information is based on the charcoal identified in the hearth deposits of wood species including cedar that only grows in drier, upland environments in Morocco today. Small mammals, including desert-edge species such as jirds (brought into the cave by natural predators like owls) help prove that the climate was much drier at this point in the past.

The shell beads have been closely studied by Francesco d’Errico and Marian Vanhaeren of the French CNRS who have confirmed that they are a shallow marine species gathered from the beach, which even in the past lay more than 40 km from the cave. Once collected, the dead shells were then probably perforated, ochred and used as personal ornaments. Some of the beads show microscopic wear patterns that would suggest they were suspended from a necklace or bracelet. The application of red pigment may have been intended to give them added visual symbolic value. There can be no doubt at all that this was part of a very deliberate cultural practice.

The beads are all the more extraordinary because the same types of marine tick shell (Nassarius) were used for making beads at a number of other Middle Palaeolithic sites in Africa and the Near East. D’Errico points out that “beads in the same shell species as at Taforalt, have also been found at Djebbana (in Algeria) and Skhul (in the Near East), and Nassarius shells of the same genus were employed at Blombos Cave, a site located at the other end of the continent in South Africa”. The new dating for Taforalt is older than at any of the other African sites and demonstrates that some time after 100,000 years ago personal ornamentation came into widespread use in Africa and the Near East. Preliminary work by the team has also shown that Nassarius shells are not isolated occurrences but are present at various other sites in Morocco. Dating evidence is still awaited for these and they may turn out to be as old or even older than Taforalt.

There is yet another twist: unlike in the Upper Palaeolithic of Europe, in which more than 150 bead types have been recorded in association with a single cultural grouping, only one or two different shell types are found at the much earlier sites stretching the length of Africa. It suggests that the role beads played in African and Near Eastern Homo sapiens societies may have been different from the one personal ornaments had in the Upper Palaeolithic of Europe. According to Vanhaeren the pattern seen in Africa “seems to match more closely the functions of beads among recent African hunter-gatherers where they were used as exchange media to reinforce reciprocity networks, thereby ensuring the survival of human groups in times of stress.” These emblems of cultural identity may have been vital for guaranteeing group survival during periods of rapidly fluctuating climate and especially under intensely arid conditions of the kind recorded at Taforalt.
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PostPosted: Sat Jun 23, 2007 7:32 am    Post subject: Human Behavior Reply with quote

Human Behavior


http://www.psychologicalscience.org/onlyhuman/
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PostPosted: Tue Jun 26, 2007 10:57 am    Post subject: How Fish Punish ‘Queue Jumpers’ Reply with quote

June 27, 2007

How Fish Punish ‘Queue Jumpers’

ARC Centre of Excellence for Coral Reef Studies

Fish use the threat of punishment to keep would-be jumpers in the mating queue firmly in line and the social order stable, a new study led by Australian marine scientists has found.

Their discovery, which has implications for the whole animal kingdom including humans, has been hailed by some of the world’s leading biologists as a “must read” scientific paper and published in the Proceedings of the Royal Society of London Series B.

Studying small goby fish at Lizard Island on Australia’s Great Barrier Reef, Dr Marian Wong and colleagues from the ARC Centre of Excellence for Coral Reef Studies at James Cook University and, the Biological Station of Donana, Spain, have shown the threat of expulsion from the group acts as a powerful deterrent to keep subordinate fish from challenging those more dominant than themselves.

In fact the subordinate fish deliberately diet - or starve themselves - in order to remain smaller than their superiors and so present no threat that might lead to their being cast out, and perishing as a result.

“Many animals have social queues in which the smaller members wait their turn before they can mate. We wanted to find out how they maintain stability in a situation where you’d expect there would be a lot of competition,” says Dr Wong.

In the case of the gobies, only the top male and top female mate, and all the other females have to wait their turn in a queue based on their size – the fishy equivalent of the barnyard pecking order.

Dr Wong found that each fish has a size difference of about 5 per cent from the one above and the one below it in the queue. If the difference in size decreases below this threshold, a challenge is on as the junior fish tries to jump the mating queue – and the superior one responds by trying to drive it out of the group.

Her fascinating discovery is that, in order to avoid constant fights and keep the social order stable, the fish seem to accept the threat of punishment – and adjust their own size in order to avoid presenting a challenge to the one above them, she says.

“Social hierarchies are very stable in these fish and in practice challenges and expulsions are extremely rare – probably because expulsion from the group and the coral reef it occupies means almost certain death to the loser.

“It is clear the fish accept the threat of punishment and co-operate as a way of maintaining their social order – and that’s not so very different to how humans and other animals behave.”

Dr Wong said that experimentally it has always proved extremely difficult to demonstrate how higher animals, such as apes, use punishment to control subordinates and discourage anti-social activity because of the difficulty in observing and interpreting their behaviour.

In the case of the gobies the effect is much more apparent because they seek to maintain a particular size ratio relative to the fish above them in the queue, in order not to provoke a conflict.

“The gobies have shed new light on our understanding of how social stability is maintained in animals,” she says.

“While it not be accurate to draw a direct link between fish behaviour and specific human behaviour, it is clear there are general patterns of behaviour which apply to many higher life forms, ourselves included. These help us to understand why we do the things we do.”

The paper entitled “The threat of punishment enforces peaceful cooperation and stabilizes queues in a coral-reef fish” was co-authored with Dr Philip Munday and Professor Geoff Jones of CoECRS and Dr Peter Buston of.the Biological Station of Doñana, Spain. It appears in Proceedings of the Royal Society B, 274.

It has received a high “must read” ranking from the Faculty of 1000 Biology, which consists of leading international biological scientists.

Dr Wong has recently been appointed to a postdoctoral research position at Canada’s McMaster University.
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PostPosted: Wed Jun 27, 2007 8:52 am    Post subject: Subordinate Fish Starve to Avoid Conflict Reply with quote

Subordinate Fish Starve to Avoid Conflict
By Jeanna Bryner, LiveScience Staff Writer

posted: 27 June 2007 09:27 am ET

Dieting in the fish world can be the ticket to survival. Goby fish starve themselves so they can stay smaller than their superiors and present no threat that could lead to eviction from the group and, likely, death.

A new study reveals how the threat of punishment can keep coral-dwelling goby fish (Paragobiodon xanthosomus) from trying to climb the social ladder and to instead accept, and even work to maintain, their subordinate status. The result is a stable, non-competitive group.

In goby societies, only the top male and top female mate. The other females have to wait in line, the order of which is based on their relative sizes, to achieve alpha breeding status.

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http://www.livescience.com/ani.....inate.html
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PostPosted: Thu Jun 28, 2007 8:22 am    Post subject: Iguanas Die to Find Mr. Right Reply with quote

Iguanas Die to Find Mr. Right
By Andrea Thompson, LiveScience Staff Writer

posted: 27 June 2007 10:01 am ET

Decisions, decisions. Picking a mate from a long line of suitors is an exhausting process for a female iguana. In fact, it can really kill her.

Scientists have generally assumed that being choosy about a mate carried a low cost for female animals, particularly when those males roam territories that are tightly clustered into groups called leks, because the females don’t have to travel very far to check out their prospects.

But the female Galápagos marine iguana spends a lot of energy choosing her mate, even though all she seems to get from the effort is better genetic material for her young. And visiting the more “attractive” males that provide this high-quality DNA (those that display more often) carries the highest costs in energy for the female because she can lose more weight and therefore produces smaller eggs.

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http://www.livescience.com/ani.....uanas.html
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PostPosted: Thu Jul 05, 2007 12:21 pm    Post subject: Amoebae control cheating by keeping it in the family Reply with quote

Rice University

Amoebae control cheating by keeping it in the family

Study shows social amoeba's association with kin controls single-celled cheaters
HOUSTON, July 5, 2007 -- No one likes a cheater, even a single-celled one.

New research from Rice University shows how cooperative single-celled amoebae rely on family ties to keep cheaters from undermining the health of their colonies. The research appeared in the Proceedings of the National Academy of Sciences in May.

"It's very unusual to get a complete story in biology -- one that marries careful field work with painstaking work in the laboratory -- and that's what we have here," said research co-author Joan Strassmann, chair of Rice's Department of Ecology and Evolutionary Biology.

Rice's research involved the common soil microbe Dictyostelium discoideum. These amoebae can be loners in times of plenty, but when food is scarce they work together, forming colonies to ensure their survival. About one fifth of the individuals in a colony form a tall, thin stalk. The rest climb the stalk and clump together into a bulbous fruiting body that can be carried away to better environs by the wind or on the legs of passing insects.

This simple social system poses an evolutionary conundrum for biologists; the members of the stalk give themselves up altruistically to support the colony, so what's to keep more selfish strains of D. discoideum from cheating the system, avoiding the stalk and out-reproducing their altruistic neighbors"

Strassmann and Rice evolutionary biologist David Queller have previously investigated how Dictyostelium colonies control cheating. For example, a study on D. discoideum showed that one gene governing cooperative behavior was also tied to reproduction. In another study, mutants that were genetically predisposed to avoid altruistic service in the stalk were also excluded from reproducing. A third study demonstrated that Dictyostelium purpureum preferentially associated with its own kin -- another mechanism that ensures altruism isn't taken advantage of by cheaters.

The current study combined graduate student Owen Gilbert's careful field and lab work on natural D. discoideum clones with exacting studies of genetically engineered mutant strains conducted by former postdoctoral researcher Kevin Foster and postdoctoral researcher Natasha Mehdiabadi.

"This work required investigators skilled in both field biology and molecular biology, an all-too-rare combination," Strassmann said.

Gilbert collected 144 D. discoideum fruiting bodies -- some of which were the first ever reported in the wild -- from 2003 to 2005 at the University of Virginia's Mountain Lake Biological Station in the Appalachian Mountains of southwestern Virginia. Back in the lab, Gilbert broke open the fruiting bodies and deciphered the genetic makeup of more than 3,000 individual spores. Though he found genetic differences between fruiting bodies, the spores within particular fruiting bodies were highly related.

Foster and Mehdiabadi worked with a mutant form of D. discoideum called "cheater A" that was missing a single gene known to play roles in both group productivity and reproduction. On their own, cheater A mutants produced few or no spores, but in mixed colonies they could thrive by cheating and avoiding service in the stalk. Foster and Mehdiabadi found cheater A spread readily within low-related colonies, and exacted a high toll by reducing the colonies' ability to reproduce. In colonies with highly related cells, the cheater's individual advantages were outweighed by the overall health of the group, so the cheaters couldn't gain a foothold.

"The combination of these two studies confirms something that's been long predicted by kin selection theory -- a mutant that cheats when relatedness is low cannot and has not spread in the wild because of natural relatedness," Queller said.

Gilbert said, "Our results answer the big question of why altruism persists. It persists because high relatedness prevents the spread of socially destructive mutants."

###
The research was sponsored by the National Science Foundation.
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PostPosted: Thu Jul 26, 2007 1:24 pm    Post subject: Crayfish Fighting and the Art of Bluffing Reply with quote

Crayfish Fighting and the Art of Bluffing
By Charles Q. Choi, Special to LiveScience

posted: 26 July 2007 08:23 am ET

A male crayfish with larger-than-normal claws typically needs only to flash his menacing weapons to drive opponents away. Now researchers find these critters are frequently bluffing—the enlarged claws often aren't stronger at all.

These findings raise the question of how often males in the animal kingdom are just bluffing with their natural weaponry.

For the full article:

http://www.livescience.com/ani.....ffing.html
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PostPosted: Thu Aug 09, 2007 3:14 pm    Post subject: Greatest Mysteries: How Did Human Culture Evolve? Reply with quote

Greatest Mysteries: How Did Human Culture Evolve?
By Andrea Thompson, LiveScience Staff Writer

posted: 09 August 2007 09:29 am ET


Shakespeare, hip hop, airplanes and millions of other innovations are all products of one of mankind's most distinguishing characteristics: human culture.

While it's clear that our brains hold a remarkable capacity to think and create, other animals demonstrate what some consider cultural behaviors. How the astounding complexity and diversity of human cultures sprang from the much simpler traditions found in animal communities has remained a puzzle.

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http://www.livescience.com/str.....lture.html
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PostPosted: Sun Aug 26, 2007 8:13 am    Post subject: Social parasites of the smaller kind Reply with quote

University of Chicago Press Journals
24 August 2007

Social parasites of the smaller kind
Microbial cheats orchestrate their own downfall

Cooperation is widespread in the natural world but so too are cheats – mutants that do not contribute to the collective good but simply reap the benefits of others’ cooperative efforts. In evolutionary terms, cheats should indeed prosper, so how cooperation persists despite the threat of cheat takeover is a fundamental question. Recently, biologists at the Universities of Edinburgh and Oxford have found that in bacteria, cheats actually orchestrate their own downfall.

In the study, reported in the September issue of The American Naturalist, the team explored the impact of cheats in populations of the notorious pathogen, Pseudomonas aeruginosa. These bacteria cooperate to scavenge iron from their environment, but mutant cheats do not contribute their fair share of scavenger molecules and instead simply steal the iron supplies of others.

“Cheats are kept in check by simple frequency dependence,” says Adin Ross-Gillespie, lead author of the study. “When rare, cheats prosper at the expense of cooperators, but as they become more common, the profitability of their strategy declines. At equilibrium, neither strategy has the upper hand, so the two coexist.”

But, the authors note, this pattern arises only under certain conditions. In this case, it arose because population productivity, too, was sensitive to the frequency of cheats. Cultures with few cheats grew rapidly and achieved larger absolute sizes in the time available, providing greater opportunity for cheats to exploit the situation. Meanwhile, cultures comprising high proportions of cheats grew poorly. “Too many cheats spoil the broth,” quips Ross-Gillespie.

Microbes cooperate extensively, and their social activities often have profound medical or economic importance. Studies such as this help us to better understand how cooperative traits evolve and persist. Who knows" Perhaps some day we will harness the power of cheats to direct the dynamics of bacterial populations.
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PostPosted: Thu Sep 27, 2007 4:09 pm    Post subject: Wasp genetics study suggests altruism evolved from maternal Reply with quote

University of Illinois at Urbana-Champaign
27 September 2007

Wasp genetics study suggests altruism evolved from maternal behavior

Researchers at the University of Illinois have used an innovative approach to reveal the molecular basis of altruistic behavior in wasps. The research team focused on the expression of behavior-related genes in Polistes metricus paper wasps, a species for which little genetic data was available when the study was begun. Their findings appear today online in Science Express.

For the full article:

http://www.eurekalert.org/pub_.....092707.php
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PostPosted: Sat Oct 06, 2007 10:02 am    Post subject: Fair Play in Chimpanzees Reply with quote

October 5th, 2007
Max Planck Society

Fair Play in Chimpanzees

Unlike humans chimpanzees do not show a willingness to make fair offers and reject unfair ones.

New research from the Max Planck Institute of Evolutionary Anthropology in Leipzig, Germany shows that unlike humans, chimpanzees conform to traditional economic models. The research, conducted by Keith Jensen, Josep Call and Michael Tomasello, used a modification of one of the most widely used and accepted economic tools, the ultimatum game (SCIENCE, October 5, 2007).

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http://www.mpg.de/english/illu.....e20071004/
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PostPosted: Mon Oct 08, 2007 2:50 pm    Post subject: Chimps Act Like Humans: Mine! Mine! Mine! Reply with quote

Chimps Act Like Humans: Mine! Mine! Mine!
By Charles Q. Choi, Special to LiveScience

posted: 08 October 2007 08:55 am ET

People often strangely consider something more valuable once they own it. Now scientists find this same apparently irrational behavior in chimps, a finding that could help shed light on the human mind.

For the full article:

http://www.livescience.com/ani.....wment.html
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PostPosted: Mon Oct 15, 2007 10:26 am    Post subject: The Evolution of Bullying Reply with quote

The Evolution of Bullying
By Meredith F. Small, LiveScience's Human Nature Columnist

posted: 12 October 2007 09:36 am ET

Adolescence is hell, as any 13-year-old or any parent of a 13-year-old will be happy to tell you. Most adults also remember their teen years with a shudder. Given access to the Fountain of Youth, no one would drink that far back.

No wonder. Puberty is marked by extravagant physical changes that prepare the body for reproduction. Adolescence is also a hurricane of thoughts, moods and emotions that help us discover who we are.

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http://www.livescience.com/his.....bully.html
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PostPosted: Thu Oct 18, 2007 11:47 am    Post subject: Elephants Know Good People from Bad Reply with quote

Elephants Know Good People from Bad
By Charles Q. Choi, Special to LiveScience

posted: 18 October 2007 12:06 pm ET

Elephants can apparently smell and see which humans might be out to get them, research now suggests.

As elephants roam Amboseli National Park in Kenya within sight of famed Mt. Kilimanjaro, they may run afoul of members of the Maasai or Kamba tribes. While the Kamba nowadays threaten only elephants that invade their farmland, Maasai warriors occasionally show off their virility by spearing elephants.

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http://www.livescience.com/ani.....iends.html
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PostPosted: Wed Oct 24, 2007 2:07 pm    Post subject: Animal behavior study overturned Reply with quote

British Antarctic Survey
24 October 2007

Animal behavior study overturned

An international team of scientists has overturned an ecological study on how some animals search for food. Previously it was believed that wandering albatrosses and other species forage using a Lévy flight strategy - a cluster of short moves connected by infrequent longer ones. Published this week in the journal Nature, the team discovered that further analyses and new data tell a different story for the albatrosses and possibly for other species too.

Biologists and physicists identified ‘Lévy flights’, named after the French mathematician Paul Lévy, as an efficient way for animals to search for sparse food. They have been attributed to a wide range of organisms, including zooplankton, grey seals, spider monkeys and even Peruvian fisherman.

The first attempt to demonstrate their existence in a natural biological system suggested that wandering albatrosses perform Lévy flights when searching for prey on the ocean surface - a finding followed by similar inferences about the search strategies of deer and bumblebees. However, this research shows this is not the case. Based on new high-resolution data collected from loggers attached to the legs of wandering albatrosses on the sub-Antarctic island of South Georgia, the team show that the previous claims about the Lévy flight behaviour were unfounded. They also re-analysed the existing data sets for deer and bumblebees using new statistical methods, again finding that none exhibits evidence of Lévy flights.

“It now seems the albatrosses come across food at simpler random intervals”, says lead author Dr Andrew Edwards from British Antarctic Survey (now at Fisheries and Oceans Canada). “Our work also questions whether other animals thought to exhibit Lévy flights really do all forage in the same way.”

This research improves scientists’ understanding of the foraging behaviour of the wandering albatross – an endangered species. It may also help develop a new theory for how animals forage – an essential piece in the wider ecological jigsaw puzzle.


###
Issued by the British Antarctic Survey Press Office.


Notes for Editors

Revisiting Lévy flight search patterns of wandering albatrosses, bumblebees and deer by Andrew M. Edwards, Richard A. Phillips, Nicholas W. Watkins, Mervyn P. Freeman, Eugene J. Murphy, Vsevolod Afanasyev, Sergey V. Buldyrev, M.G.E da Luz, E. P. Raposo, H. Eugene Stanley, Gandhi M. Viswanathan is published in the journal Nature on Thursday 25 October 2007.

Organisations involved in this research: British Antarctic Survey, Boston University (US), Yeshiva University (US), Universidade Federal do Parana (Brazil), Universidade Federal de Pernambuco (Brazil), Universidade Federal de Alagoas (Brazil).

A Lévy flight is named after the French mathematician Paul Pierre Lévy and is a type of random walk in which increments are distributed according to a probability distribution with a heavy power law tail.

The work at BAS forms part of the COMPLEXITY and DISCOVERY 2010 science programmes at BAS. NATURAL COMPLEXITY provides a new perspective on, and understanding of, complicated natural phenomena including biological food webs, animal foraging and iceberg calving. DISCOVERY 2010 is investigating and describing the response of an ocean ecosystem to climate variability, climate change and commercial exploitation.

The original study was published in Nature in 1996 based on albatross data collected from Bird Island Research Station in 1992. Another Nature paper in 1999 developed this idea further using data from bumblebees and deer and using computer simulation.

The wandering albatrosses inhabit Bird Island, a 5km-long rocky island off South Georgia in the South Atlantic Ocean. With no food to be found on the island, the birds undertake long foraging trips, flying close to the ocean surface to spot and feed on squid. Loggers attached to the birds’ legs tell ecologists how often the birds land on the water to feed.

Estimates suggest that 300,000 seabirds are killed annually in the world’s long-line fisheries, many of which are albatrosses. Since 2001, by-catch rates in well-regulated fisheries have decreased substantially, remained stable in less well-regulated ones and probably increased in pirate fisheries, for which no real data exist. 19 of the 21 species of albatross are threatened with extinction.

British Antarctic Survey is a world leader in research into global issues in an Antarctic context. It is the UK’s national operator and is a component of the Natural Environment Research Council ( www.nerc.ac.uk ). It has an annual budget of around £40 million, runs nine research programmes and operates five research stations, two Royal Research Ships and five aircraft in and around Antarctica. More information about the work of the Survey can be found at: www.antarctica.ac.uk

Fisheries and Oceans Canada

Fisheries and Oceans Canada is the lead federal government department responsible for developing and implementing policies and programs in support of Canada's economic, ecological and scientific interests in oceans and inland waters.
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