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PostPosted: Wed Jan 09, 2008 12:01 pm    Post subject: Scientists find cultural differences among chimpanzee coloni

University of Liverpool
9 January 2008

Scientists find cultural differences among chimpanzee colonies
Socially-learned cultural behavior thought to be unique to humans is also found among chimpanzees colonies, scientists at the University of Liverpool have found
Socially-learned cultural behaviour thought to be unique to humans is also found among chimpanzees colonies, scientists at the University of Liverpool have found.

Historically, scientists believed that behavioural differences between colonies of chimpanzees were due to variations in genetics. A team at Liverpool, however, has now discovered that variations in behaviour are down to chimpanzees migrating to other colonies, proving that they build their ‘cultures’ in a similar way to humans.

Primatologist, Dr Stephen Lycett, explains: “We knew there were behavioural differences between chimpanzee colonies, but nobody really knew why. It was assumed that young chimpanzees developed certain behavioural characteristics from the genes passed down from their parents, but there was no evidence to clearly support this. It was also thought that because behaviour was dictated by biology, chimpanzees did not have a ‘culture’ in the same way that humans do.”

By looking at how chimpanzees prepare their food, the research team discovered that one colony used stone tools to crack nuts, whereas another colony used wooden tools as well as stone. They found these methods of preparing food have spread 4000km from East to West Africa over the more than 100,000 years. The team also found this true of other techniques, such as grooming. The research suggests that behavioural variety is due to how chimpanzees socialise rather than genetics as previously thought.

To investigate the theory further researchers built an evolutionary tree of chimpanzee behaviour in East and West Africa as well as a genetic family tree. They had expected to find that those with similar genetic patterns also shared behavioural similarities. Instead, they found that some chimpanzees shared behavioural similarities with those that were genetically different from them.

Dr Lycett, added: “This explains why some colonies, for example, use similar methods for finding food, adopting certain behaviour and adapting different methods to suit their own environment. In this sense we can see for the first time that culture exists in our closest relatives.”

The research is published in Proceedings of the National Academy of Sciences USA.

Notes to editors:

1. The University of Liverpool is one of the UK's leading research institutions. It attracts collaborative and contract research commissions from a wide range of national and international organisations valued at more than £100 million annually.
PostPosted: Sat Dec 08, 2007 7:45 am    Post subject:

Week of Dec. 8, 2007; Vol. 172, No. 23 , p. 355

Chimp Champ: Ape aces memory test, outscores people
Susan Milius

OK, humanity: time to pull up our socks. In a test of rapid number recollection, college students were resoundingly outperformed by a young chimpanzee.

For the full article:
PostPosted: Mon Dec 03, 2007 2:20 pm    Post subject: Chimps Do Numbers Better Than Humans

Chimps Do Numbers Better Than Humans
By Charles Q. Choi, Special to LiveScience

posted: 03 December 2007 10:10 am ET

Young chimps apparently have an extraordinary ability to remember numerals and recall them even better than human adults do.

Although researchers have extensively studied chimpanzee memory in the past, the general assumption has been that it is inferior to that of humans, as with many other mental functions.

For the full article:
PostPosted: Thu Nov 29, 2007 5:44 pm    Post subject: Pre-Human Dating Scene Revealed

Pre-Human Dating Scene Revealed
By Dave Mosher, LiveScience Staff Writer

posted: 29 November 2007 02:07 pm ET

Humans basically court each other one-on-one today, but 2 million-year-old skulls tucked away in South African caves suggest that our ancient male relatives dated troops of females.

The bones belonged to Paranthropus robustus hominids, mostly males. These extinct human relatives split away from our evolutionary track about 2.5 million years ago. Scientists said the preponderance of male skulls, located in what were likely lairs of hyenas or leopards, offered a clear view into our close relative's social world.

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PostPosted: Thu Nov 22, 2007 11:40 am    Post subject: What Humans Should Really be Thankful For

What Humans Should Really be Thankful For
By Meredith F. Small, LiveScience's Human Nature Columnist

posted: 22 November 2007 07:54 am ET

In this season of thankfulness, it's a good idea to move beyond being thankful for more food than we could ever eat and more family than we could ever argue with and take stock of other issues in our lives that deserve a nod.

We are humans, and this species has a lot to be grateful for.

The first real human trait was bipedalism, walking on two legs, which appeared more than 4.5 million years ago. No one knows why we became bipedal, but walking upright allows us not only to cover a lot of ground in an efficient way; it also allows us to carry things, like shopping bags and purses, or a cooked turkey on a platter.

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PostPosted: Fri Nov 16, 2007 1:05 pm    Post subject: Even Monkeys Go Ga-Ga over Babies

Even Monkeys Go Ga-Ga over Babies
By Meredith F. Small, LiveScience's Human Nature Columnist

posted: 16 November 2007 12:18 pm ET

"Awww, isn’t she ad-or-a-ble?"

Nothing makes a person sound more idiotic than the presence of a new baby.

Our voices climb quickly into the stratosphere of the human vocal range and our words squeak out in a way that annoys everyone within earshot.

We also start to babble senseless, often embarrassing, phrases.

For the full article:
PostPosted: Wed Nov 14, 2007 3:12 pm    Post subject: University of Toronto finds humans and chimps differ at leve

University of Toronto
14 November 2007

University of Toronto finds humans and chimps differ at level of gene splicing

TORONTO, ON – Researchers are closer to understanding why humans differ so greatly from chimpanzees in the way they look, behave, think, and fight off disease, despite having genes that are nearly 99% identical.

Innovative research from the University of Toronto’s Centre for Cellular and Biomolecular Research has uncovered potential new explanations for these glaring differences. In comparing brain and heart tissue from humans and chimpanzees, U of T Professor Benjamin Blencowe and his team, including graduate student researcher John Calarco, have discovered significant differences in the way genetic material is spliced to create proteins.

“It’s clear that humans are very different from chimpanzees on several levels, but we wanted to find out if it could be the splicing process that accounts for some of these fundamental differences,” says Blencowe, a professor with the Banting and Best Department of Medical Research and Department of Molecular Genetics. “The surprising thing we found was that six to eight per cent of the alternative splicing events we looked at were showing differences, which is quite significant. And those genes that showed differences in splicing are associated with a range of important processes, including susceptibility to certain diseases.”

Splicing is the process by which the coding regions of genes are joined to generate genetic messages that specify the production of proteins, the key structural and functional constituents of cells. Splicing can occur in alternative ways in the same genetic message to generate more than one type of protein. The new findings reveal that the alternative splicing process differs significantly between humans and chimpanzees.

The study, appearing tomorrow in the Journal of Genes and Development, could have implications for the future study of disease in humans and chimpanzees, Blencowe says.

“Identifying what makes us different can be very important to understanding why certain diseases affect one species and not the other,” he says.
PostPosted: Tue Nov 13, 2007 1:39 pm    Post subject: Meat vs. Potatoes: What Our Chimp Ancestors Liked

Meat vs. Potatoes: What Our Chimp Ancestors Liked
By Jeanna Bryner, LiveScience Staff Writer

posted: 13 November 2007 10:43 am ET

Chimpanzees prefer to dig for tubers and roots even when aboveground snacks are plentiful, a finding that bears on questions about humans' preferences for meat versus potatoes.

Eleven chimp digging sites and associated tools discovered in the Ugalla savanna woodland of western Tanzania in Africa provide the first tangible evidence that our closest living relatives use sticks and bark to dig up underground foods.

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PostPosted: Fri Nov 02, 2007 1:45 pm    Post subject: Researchers examine closest living relative to primates

Texas A&M University

Researchers examine closest living relative to primates

COLLEGE STATION, Nov. 1, 2007 – Researchers at Texas A&M University’s College of Veterinary Medicine & Biomedical Sciences, in collaboration with scientists representing institutions around the world, have discovered the closest living relative to primates. They did so after completing a multispecies genomic comparison within the superordinal group Euarchonta, which includes primates, dermoptera (colugos) and scandentia (tree shrews). Their findings are published in the Nov. 2 edition of the journal Science.

“Determination of the closest living relative of primates has important ramifications for anthropology and genomics,” said Dr. William Murphy, a professor of veterinary integrative biosciences and team leader of the study.“In order to resolve the ancestral relationships among primates and their closest relatives, we had to compare alignments in recently sequenced genomes of multiple species, looking for rare genomic changes which would suggest evolutionary branching patterns between species. This gives us a clearer, more accurate look at how primates evolved and may help in placing fossil primates and their relatives on the evolutionary family tree.”

As conclusions of the study have indicated that colugos (flying lemurs), rather than tree shrews, are genetically more closely related to primates, further sequencing of the colugo genome is warranted, Murphy said, in order to develop a better understanding of the evolutionary changes leading to primates, as well as to more accurately reconstruct the ancestral primate genome.

According to Murphy, the origins of primates and primates found in the fossil record have been a topic of intense debate as there has been an increased focus on identifying adaptive evolutionary changes with primates. By decoding the past through changes in genomics, a clearer picture of the evolution of primates emerges that will provide a broader context for future research, he said.

The multidisciplinary approach to the genomic comparisons utilized in this study also revealed additional information that will prove beneficial to global biodiversity, Murphy added.

“In addition to identifying colugos as the closest living relative to primates, we were able to make some very important discoveries about the tree shrews,” said Murphy. “The phylogenetic uniqueness we documented in Ptilocercus, coupled with its restriction to a lowland forest habitat and limited global range, have certainly identified it as an important conservation effort in a global sense.”

The study was funded by grants from the National Science Foundation and the National Institutes of Health. The paper was led by post-doctoral researcher Jan Janecka of Texas A&M University, and involved specialists in bioinformatics and mammalogy from several institutions, including Dr. Webb Miller from Penn State University, Dr. Thomas Pringle of the Sperling Foundation, Dr. Mark Springer of the University of California at Riverside, Dr. Kristofer Helgen of the Smithsonian Institution, and Drs. Annette Zitzmann and Frank Wiens of the Johann Wolfgang Goethe-University and the University of Bayreuth, respectively.
PostPosted: Wed Oct 24, 2007 2:20 pm    Post subject: Humans and monkeys share Machiavellian intelligence

University of Chicago
24 October 2007

Humans and monkeys share Machiavellian intelligence

When it comes to their social behavior, people sometimes act like monkeys, or more specifically, like rhesus macaques, a type of monkey that shares with humans strong tendencies for nepotism and political maneuvering, according to research by Dario Maestripieri, an expert on primate behavior and an Associate Professor in Comparative Human Development and Evolutionary Biology at the University of Chicago.

“After humans, rhesus macaques are one of the most successful primate species on our planet; our Machiavellian intelligence may be one of the reasons for our success” wrote Maestripieri in his new book Macachiavellian Intelligence: How Rhesus Macaques and Humans Have Conquered the World.

Maestripieri has been studying monkeys for more than 20 years and has written extensively on their behavior. He has studied them in Europe, at a research center in Atlanta, and on an island in Puerto Rico, where researchers established a rhesus macaque colony for scientific and breeding purposes.

Rhesus macaques live in complex societies with strong dominance hierarchies and long-lasting social bonds between female relatives. Individuals constantly compete for high social status and the power that comes with it using ruthless aggression, nepotism, and complex political alliances. Sex, too, can be used for political purposes. The tactics used by monkeys to increase or maintain their power are not much different from those Machiavelli suggested political leaders use during the Renaissance.

Alpha males, who rule the 50 or so macaques in the troop, use threats and violence to hold on to the safest sleeping places, the best food, and access to the females in the group with whom they want to have sex. Like human dictators intent on holding power, dominant monkeys use frequent and unpredictable aggression as an effective form of intimidation. Less powerful members of the rhesus macaque group are marginalized and forced to live on the edges of the group’s area, where they are vulnerable to predator attacks. They must wait for the others to eat first and then have the leftovers; they have sex only when the dominant monkeys are not looking.

“In rhesus society, dominants always travel in business class and subordinates in economy, and if the flight is overbooked, it’s the subordinates who get bumped off the plane,” Maestripieri said. “Social status can make the difference between life and death in human societies too,” he pointed out. In the wake of Hurricane Katrina, for instance, the poorer members of the community accounted for most of the hurricane’s death toll.

Male macaques form alliances with more powerful individuals, and take part in scapegoating on the lower end of the hierarchy, a Machiavellian strategy that a mid-ranking monkey can use when under attack from a higher-ranking one. Altruism is rare and, in most cases, only a form of nepotistic behavior. Mothers help their daughters achieve a status similar to their own and to maintain it throughout their lives. Females act in Machiavellian ways also when it comes to reproduction. They make sure they have lots of sex with the alpha male to increase the chances he will protect their newborn infant from other monkeys 6 months later.

“But while they have lots of sex with the alpha male and make him think he’s going to be the father of their baby, the females also have sex with all the other males in the group behind the alpha male’s back,” Maestripieri said. They do so just in case the alpha male is sterile or he dies or loses his power before the baby is born.

Struggles for power within a group sometimes culminate in a revolution, in which all members of the most dominant family are suddenly attacked by entire families of subordinates. These revolutions result in drastic changes in the structure of power within rhesus societies, not unlike those occurring following human revolutions. There is one situation, however, in which all of the well-established social structure evaporates: when a group of rhesus macaques confronts another one and monkey warfare begins. Rhesus macaques dislike strangers and will viciously attack their own image in a mirror, thinking it’s a stranger threatening them. When warfare begins, “Even a low-ranking rhesus loner becomes an instant patriot. Every drop of xenophobia in rhesus blood is transformed into fuel for battle,” Maestripieri wrote.

“What rhesus macaques and humans may have in common is that many of their psychological and behavioral dispositions have been shaped by intense competition between individuals and groups during the evolutionary history of these species” Maestripieri said. Rhesus groups can function like armies, and this may explain why these monkeys have been so successful in the competition with other primates.

Pressure to find Machiavellian solutions to social problems may also have led to the evolution of larger human brains.

“Our Machiavellian intelligence is not something we can be proud of, but it may be the secret of our success. If it contributed to the evolution of our large brains and complex cognitive skills, it also contributed to the evolution of our ability to engage in noble spiritual and intellectual activities, including our love and compassion for other people”, Maestripieri said.
PostPosted: Sat Sep 22, 2007 9:49 am    Post subject: Evidence in Hand That 'Hobbit' Was Not a Modern Human

Evidence in Hand That 'Hobbit' Was Not a Modern Human
By Jeanna Bryner, LiveScience Staff Writer

posted: 20 September 2007 02:05 pm ET

A smoking gun that could snuff out a hot debate over skeletal remains dubbed "the hobbit" is in hand, literally, according to a group of scientists.

Three wrist bones provide key evidence supporting the argument that fossil remains of an ancient, undersized individual represent a new hominin species that walked the Earth with modern humans, say the study scientists.

For the full article:
PostPosted: Wed Sep 05, 2007 1:04 pm    Post subject: Leafing Through Magazines, Chimps Exhibit Self-Control

Leafing Through Magazines, Chimps Exhibit Self-Control
By Charles Q. Choi, Special to LiveScience

posted: 05 September 2007 07:58 am ET

Chimpanzees are masters of the sudden outburst, throwing apparent fits that can involve loud screeches and hurling things. But they also know how to control themselves.

When attempting to avoid temptation, chimps resist their urges by distracting themselves, a new study suggests.

The finding could shed light on the evolution of human self-control, researchers said.

For the full article:
PostPosted: Fri Aug 24, 2007 9:57 am    Post subject: Monkeys use 'baby talk' to interact with infants

University of Chicago
24 August 2007

Monkeys use 'baby talk' to interact with infants

Female rhesus monkeys use special vocalizations while interacting with infants, the way human adults use motherese, or “baby talk,” to engage babies’ attention, new research at the University of Chicago shows. “Motherese is a high pitched and musical form of speech, which may be biological in origin,” said Dario Maestripieri, Associate Professor in Comparative Human Development at the University. “The acoustic structure of particular monkey vocalizations called girneys may be adaptively designed to attract young infants and engage their attention, similar to how the acoustic structure of human motherese, or baby talk, allows adults to visually or socially engage with infants.”
In order to determine if other primates also use special vocalizations while interacting with infants, researchers studied a group of free-ranging rhesus macaques, which live on an island off the coast of Puerto Rico. They studied the vocalizations exchanged between adult females and found that grunts and girneys increased dramatically when a baby was present. They also found that when a baby wandered away from its mother, the other females looked at the baby and vocalized, suggesting that the call was intended for the baby.

“Adult females become highly aroused while observing the infants of other group members,” explains lead author of the article, Jessica Whitham, a recent Ph.D. graduate of the University of Chicago, who investigated this topic as a doctoral student at the University and currently works at Brookfield Zoo near Chicago. “While intently watching infants, females excitedly wag their tails and emit long strings of grunts and girneys.

“The calls appear to be used to elicit infants’ attention and encourage their behavior. They also have the effect of increasing social tolerance in the mother and facilitating the interactions between females with babies in general. Thus, the attraction to other females’ infants results in a relatively relaxed context of interaction where the main focus of attention is the baby,” Maestripieri and his colleagues write in the article, “Intended Receivers and Functional Significance of Grunt and Girney Vocalizations in Free-Ranging Rhesus Macaques” published in the current issue of the journal Ethology. In addition to Whitham and Maestripieri, Dr. Melissa Gerald, a researcher at the University of Puerto Rico, was also a co-author.

Researchers have long been interested in the noises that non-human primates make and how they are used for communication. Monkey vocalizations could be carrying information that the sender expects the recipient to understand, or they could be noises that the recipient can draw inferences from, but are not intended to carry information. A human sneeze, for instance, is a noise that people understand may be associated with a cold, but it did not develop evolutionarily to convey information.

The study by Maestripieri’s team showed that the grunts and girneys emitted by the rhesus macaques fall into the category of vocalizations not intended to convey specific information, and appear to be used to attract other individuals’ attention or change their emotional states. When females vocalize to young infants, however, the infants’ mothers infer that the females simply want to play with the infants and are unlikely to harm them. Therefore, these vocalizations may facilitate adult females’ interactions not only with infants, but with the infants’ mothers as well. They found, for instance, that the grunts and girneys were sometimes followed by an approach and grooming of the mothers.

Additionally they discovered that, unlike human mothers, the rhesus macaque mothers did not direct grunts or girneys toward their own offspring. It could be that the monkey mothers are familiar with their own offspring and use the vocalizations with other babies because they are excited about the novelty of seeing a new infant, Maestripieri said.
PostPosted: Thu Aug 23, 2007 9:17 am    Post subject: Newfound Species Pushes Back Human-Ape Split

Newfound Species Pushes Back Human-Ape Split
By Ker Than, LiveScience Staff Writer

posted: 22 August 2007 01:00 pm ET

Recently unearthed fossils belonging to a new ape species suggest the lineages leading to humans and gorillas split several million years earlier than previously thought.

Found in Ethiopia, the 10 million-year-old fossilized teeth resemble those of modern gorillas and appear specialized for eating fibrous foods such as stems and leaves.

For the full article:
PostPosted: Sat Aug 04, 2007 10:38 am    Post subject: Red-Ape Stroll

Week of Aug. 4, 2007; Vol. 172, No. 5 , p. 72

Red-Ape Stroll
Orangutans step into the evolutionary fray over how we became upright
Bruce Bower

Look, up in the trees. A barrel-chested, long-limbed creature covered with wispy, reddish hair sits on a branch far above the ground. The animal rises to a fully erect posture, reaches up to grab an overhead branch for balance, and promenades across the precarious platform. Upon reaching a cluster of hanging fruit, the animal plucks off a snack with a free hand.

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PostPosted: Thu Aug 02, 2007 2:50 pm    Post subject: Sounds Like ... Apes Play Charades

Sounds Like ... Apes Play Charades
By Charles Q. Choi, Special to LiveScience

posted: 01 August 2007 08:22 pm ET

When humans play charades, the game's ban on talk often reduces players to wild gestures in a frustratingly minimalist form of communication. Still, skillful players get the point across eventually.

Apes can't talk at all, of course. But now scientists have found that orangutans rely on the same kinds of strategies seen in charades when they try and get their point across.

The finding hints at how the earliest forms of language might have developed among humanity's ancestors.

For the full article:
PostPosted: Wed Aug 01, 2007 12:35 pm    Post subject: Monkeys learn in the same way as humans, psychologists repor

University of California - Los Angeles
1 August 2007

Monkeys learn in the same way as humans, psychologists report

Monkeys seem to learn the same way humans do, a new research study indicates.

“Like humans, monkeys benefit enormously from being actively involved in learning instead of having information presented to them passively,” said Nate Kornell, a UCLA postdoctoral scholar in psychology and lead author of the study, which appears in the August issue of the journal Psychological Science. “The advantage of active learning appears to be a fundamental property of memory in humans and nonhumans alike.”

In Kornell’s study, conducted when he was a psychology graduate student at Columbia University, two rhesus macaque monkeys learned to place five photographs in a particular order. The photographs were displayed on a touch-screen computer monitor similar to those found on ATMs. When the monkeys pressed a correct photograph, a border appeared around it. When either monkey pressed all five photographs in the correct order, he received a food reward. The chance of guessing all five accurately is less than one percent.

In all, each monkey learned to order at least 18 separate series of photographs, which included such items as a fish, a human face, a building, a football field and a flame from a match. They underwent three of training before being tested.

In some of the training trials, the monkeys had to figure out the correct order themselves, while in others, they had the option of getting help by pushing an icon in the corner of the screen that caused the border of the correct photograph to flash. They were rewarded with an M&M candy each time they correctly completed the task without help and with a less desirable food pellet when they completed the task with hints from the help icon. After three days, the monkeys were tested without the benefit of the help icon.

“Both monkeys did much better if they had studied without a hint than if they had studied with a hint,” Kornell said. “The monkeys did much better on the first three days when they had the help than when they didn’t, but on the test day, it completely reversed. When they studied with the hint, there is no evidence they learned anything about the list. They learned the lists when they didn’t get the help.” The findings are closely related to findings in humans that recalling answers from memory enhances long-term learning.

“The findings were somewhat unintuitive, because passively using the hint appeared to enhance performance during the study phase of the experiment but had a deleterious effect on long-term learning,” Kornell said.

What are the implications for human learning?

“Many people incorrectly assume the better you do as you’re studying, the more you’re learning,” said Kornell, who works in the laboratory of Robert A. Bjork, professor and chair of psychology at UCLA. “If students don’t test themselves when they read a chapter, they can easily think they know the material when they don’t. When you test yourself as you study, you may feel like you’re making it harder on yourself, but on the test, you will do much better. Robert Bjork calls this ‘desirable difficulty.’ If you want to learn something well, when you’re reading, stop and think about what you’ve read, and test yourself; you learn by testing yourself. If you make it more difficult for yourself while you study, you feel like you’re doing worse, but you’re learning more.

“Active learning is important in humans and — this study demonstrates — in monkeys as well,” he added.

Less effective passive learning includes listening to a presentation and reading without testing yourself or summarizing what you have learned.

“When you summarize the material in your own words, that’s much more active,” Kornell said. “You can’t do that if you don’t understand it.”

Cramming right before a test does not work as well as spacing studying out over a longer period of time, Kornell added, citing other research on learning and memory.

Kornell’s research, supported by the National Institute of Mental Health, was conducted with Herbert Terrace, a professor of psychology at Columbia. The two monkeys, Macduff and Oberon, are housed at the New York State Psychiatric Institute, where Terrace has a joint appointment. Neither animal was harmed in the study, and they were fed daily regardless of how they performed in the trials.

“Many people,” Kornell noted, “have had the experience of listening to a computer instructor open a menu and go through a series of steps. Then you try to do it, and you don’t even know which menu or what the first step is. If you are passively following along, you won’t remember it as well as if you’re forced to do it yourself. Active learning is much harder, but if you can do it successfully, you will remember it much better in the long run.

“If you’re learning to serve a tennis ball, you won’t get much out of an instructor taking your arm and practicing the swing over and over,” he said. “That’s not going to help you nearly as much as if you serve the ball yourself.”

The situation is the same for monkeys, according to Kornell.

“The way the monkeys learn to remember the correct answers is through active learning, like humans,” he said. “They have to generate the answers themselves from memory. Generating the correct sequence from memory resulted in more long-term learning than the more passive training with hints.”

Kornell noted that more than a century ago, author William James remarked on the importance of being actively involved in learning. Since then, science has proven him correct. Kornell also noted that his research confirms the teachings of another monkey: Curious George.

UCLA is California’s largest university, with an enrollment of nearly 37,000 undergraduate and graduate students. The UCLA College of Letters and Science and the university’s 11 professional schools feature renowned faculty and offer more than 300 degree programs and majors. UCLA is a national and international leader in the breadth and quality of its academic, research, health care, cultural, continuing education and athletic programs. Four alumni and five faculty have been awarded the Nobel Prize.
PostPosted: Tue Jul 24, 2007 5:16 pm    Post subject: Study Sheds Light on Why Humans Walk on Two Legs

Study Sheds Light on Why Humans Walk on Two Legs
July 20, 2007
UC Davis

A team of anthropologists that studied chimpanzees trained to use treadmills has gathered new evidence suggesting that our earliest apelike ancestors started walking on two legs because it required less energy than getting around on all fours.

For the full article:
PostPosted: Thu Jul 19, 2007 8:45 am    Post subject: Scientist: Human Origin Impossible to Pinpoint

Scientist: Human Origin Impossible to Pinpoint
By Jeanna Bryner, LiveScience Staff Writer

posted: 18 July 2007 01:03 pm ET

All modern humans originated in sub-Saharan Africa, according to a new study touted by its funders as the “final blow” against an opposing viewpoint. Not so fast, says one anthropologist who finds flaws in the evidence.

Debate over the origins of modern humans has simmered among anthropologists for years, with one theory asserting that Homo sapiens migrated across the world from a single point in Africa. The other theory states that multiple populations of Homo sapiens independently evolved from Homo erectus in regions beyond Africa.

For the full article:
PostPosted: Tue Jul 17, 2007 7:34 am    Post subject: Why We Walk Upright: Beats Being a Chimp

Why We Walk Upright: Beats Being a Chimp
By Ker Than, LiveScience Staff Writer

posted: 16 July 2007 05:06 pm ET

Humans walking on two legs consume only a quarter of the energy that chimpanzees use while “knuckle-walking” on all fours, according to a new study.

The finding, detailed in the July 17 issue of the journal for the Proceedings of the National Academy of Sciences, supports the idea that early humans became bipedal as a way to reduce energy costs associated with moving about.

“Walking upright on two legs is a defining feature that makes us human,” said study leader Herman Pontzer, an anthropologist at Washington University in St. Louis. “It distinguishes our entire lineage from all other apes.”

According to this theory, the energy saved by walking upright gave our ancient ancestors an evolutionary advantage over other apes by reducing the costs of foraging for food.

The idea is just one of many scientists have entertained as reasons for why humans walk on two legs. Recent studies have also suggested that, rather than taking millions of years to evolve from a hunched position as is commonly believed, our early ancestors were already capable of standing and walking upright the moment they descended from the trees.

For the full article:
PostPosted: Fri Jul 13, 2007 12:18 pm    Post subject: Talk, Talk, Talk: One Thing We Do Better than Apes

Talk, Talk, Talk: One Thing We Do Better than Apes
By Meredith F. Small

posted: 13 July 2007 09:00 am ET

Anthropologists and others used to have a list of behaviors that separated us from the apes. Humans were the only ones to use tools, utilize culture, have complex feelings and communicate by language.

But over the years, each one of these so-called uniquely human abilities, except language, has fallen by the wayside.

For example, chimps expertly crack nuts using stones of just the right heft, fish for termites with finely fashioned stick rods and soak up rainwater with nicely crumpled leaf sponges.

And over the range of chimpanzees, differing groups take on signature behaviors that can only be considered cultural, even multicultural.

For the full article:
PostPosted: Sat Jun 30, 2007 8:44 am    Post subject: Ape Aid: Chimps share altruistic capacity with people

Week of June 30, 2007; Vol. 171, No. 26 , p. 406

Ape Aid: Chimps share altruistic capacity with people
Bruce Bower

Many researchers have asserted that only people will assist strangers without receiving anything in return, sometimes at great personal cost. However, a new study suggests that chimpanzees also belong to the Good Samaritan club, as do children as young as 18 months of age.

For the full article:
PostPosted: Mon Jun 25, 2007 11:36 am    Post subject: Selfless Chimps Shed Light on Evolution of Altruism

Selfless Chimps Shed Light on Evolution of Altruism
By Charles Q. Choi, Special to LiveScience

posted: 25 June 2007 10:19 am ET

Chimpanzees have now shown they can help strangers at personal cost without apparent expectation of personal gain, a level of selfless behavior often claimed as unique to humans.

These new findings could shed light on the evolution of such altruism, researchers said.

Scientists think altruism evolved to help either kin or those willing and able of returning the favor—to help either one's genetic heritage or oneself. Humans, on the other hand, occasionally help strangers without apparent benefit for themselves, sometimes at great cost.

For the full article:
PostPosted: Mon Jun 18, 2007 9:04 am    Post subject: Human Nature Rubs Off on Chimps

Human Nature Rubs Off on Chimps
By Charles Q. Choi, Special to LiveScience

posted: 18 June 2007 08:55 am ET

A bit of human nature can apparently rub off on chimpanzees. Chimps nurtured by humans since birth have a far better chance of figuring out how to use new tools, a new study shows.

The findings highlight untapped potential within chimpanzees that can get uncovered "by studying them when they have been raised under very comparable conditions as our own children," said Ohio State University cognitive primatologist Sally Boysen.

The research suggests that early human ancestors may have been far more sophisticated in their mental capacities than previously thought, she added.

"The emergence of higher order thinking, as well as motor skills that would permit complex tool use and construction and other cultural features of human social interaction, may have been part of our human ancestry much earlier than otherwise predicted by the fossil record of artifacts and human remains," Boysen told LiveScience.

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PostPosted: Fri Jun 08, 2007 9:38 am    Post subject: Chimps Pass On Culture Like Humans Do

Chimps Pass On Culture Like Humans Do
By Charles Q. Choi, Special to LiveScience

posted: 08 June 2007 8:35 am ET

Chimpanzees readily learn and share techniques on how to fiddle with gadgets, new research shows, the best evidence yet that our closest living relatives pass on customs and culture just as humans do.

The new findings help shed light on the capabilities of last common ancestor of humans and chimps. And the research could also help develop better robots and artificial intelligences, the researchers say

In the wild, chimpanzee troops are often distinct from one another, possessing collections of up to 20 traditions or customary behaviors that altogether seem to form unique cultures. Such practices include various forms of tool use, including hammers and pestles; courtship rituals such as leaf-clipping, where leaves are clipped noisily with the teeth; social behaviors such as overhead hand-clasping during mutual grooming; and methods for eradicating parasites by either stabbing or squashing them.

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