May 3, 2013
11.9 Million Year Old Fossil Of Great Ape Sheds Light On Evolution

Researchers who unearthed the fossil specimen of an ape skeleton in Spain in 2002 assigned it a new genus and species, Pierolapithecus catalaunicus. They estimated that the ape lived about 11.9 million years ago, arguing that it could be the last common ancestor of modern great apes: chimpanzees, orangutans, bonobos, gorillas and humans. Now, a University of Missouri integrative anatomy expert says the shape of the specimen’s pelvis indicates that it lived near the beginning of the great ape evolution, after the lesser apes had started to develop separately but before the great ape species began to diversify.

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Ashley Hammond, a Life Sciences Fellow in the MU Department of Pathology and Anatomical Sciences, is the first to examine the pelvis fragments of the early hominid. She used a tabletop laser scanner attached to a turntable to capture detailed surface images of the fossil, which provided her with a 3-D model to compare the Pierolapithecus pelvis anatomy to living species.

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Hammond says the ilium, the largest bone in the pelvis, of the Pierolapithecus catalaunicus is wider than that of Proconsul nyanzae, a more primitive ape that lived approximately 18 million years ago. The wider pelvis may be related to the ape’s greater lateral balance and stability while moving using its forelimbs. However, the fingers of the Pierolapithecus catalaunicus are unlike those of modern great apes, indicating that great apes may have evolved differently than scientists originally hypothesized.

“Pierolapithecus catalaunicus seemed to use a lot of upright behaviors such as vertical climbing, but not the fully suspensory behaviors we see in great apes alive today,” Hammond said. “Today, chimpanzees, orangutans, bonobos and gorillas use forelimb-dominated behaviors to swing below branches, but Pierolapithecus catalaunicus didn’t have the long, curved finger bones needed for suspension, so those behaviors evolved more recently.”

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Hammond suggests researchers continue searching for fossils to further explain the evolution of the great apes in Africa.

“Contrary to popular belief, we’re not looking for a missing link,” Hammond said. “We have different pieces of the evolutionary puzzle and big gaps between points in time and fossil species. We need to continue fieldwork to identify more fossils and determine how the species are related and how they lived. Ultimately, everything is connected.”

The study, “Middle Miocene Pierolapithecus provides a first glimpse into early hominid pelvic morphology,” will be published in an upcoming issue of the Journal of Human Evolution.


From phys.org/news

10:00pm  |   URL: http://tmblr.co/Z8EaJxk8ac9K
(Notes: 2)
  
Filed under: ape primate animal science anthropology evolution primatology evolutionary anthropology 
February 12, 2013
Happy Darwin Day!

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11:22am  |   URL: http://tmblr.co/Z8EaJxd_8HxO
(Notes: 1)
  
Filed under: darwin charles darwin darwin day evolution theory science animal origin of species natural selection 
February 3, 2013

blaze-ferrari:

Evolution Simplified

(via atheismfuckyeah)

10:28am  |   URL: http://tmblr.co/Z8EaJxdI0tD4
(Notes: 53,322)
  
Filed under: animal science biology primatology anthropology evolution monkey primate ape 
January 29, 2013
Primates, Too, Can Move in Unison

Japanese researchers show for the first time that primates modify their body movements to be in tune with others, just like humans do. Humans unconsciously modify their movements to be in synchrony with their peers. For example, we adapt our pace to walk in step or clap in unison at the end of a concert. This phenomenon is thought to reflect bonding and facilitate human interaction. Researchers from the RIKEN Brain Science Institute report that pairs of macaque monkeys also spontaneously coordinate their movements to reach synchrony.

This research opens the door to much-needed neurophysiological studies of spontaneous synchronization in monkeys, which could shed light into human behavioral dysfunctions such as those observed in patients with autism spectrum disorders, echopraxia and echolalia — where patients uncontrollably imitate others.

In the research, recently published in the journal Scientific Reports, the team led by Naotaka Fujii developed an experimental set-up to test whether pairs of Japanese macaque monkeys synchronize a simple push-button movement.

Before the experiment, the monkeys were trained to push a button with one hand. In a first experiment the monkeys were paired and placed facing each other and the timing of their push-button movements was recorded. The same experiment was repeated but this time each monkey was shown videos of another monkey pushing a button at varying speeds. And in a last experiment the macaques were not allowed to either see or hear their video-partner.

The results show that the monkeys modified their movements — increased or decreased the speed of their push-button movement — to be in synchrony with their partner, both when the partner was real and on video. The speed of the button pressing movement changed to be in harmonic or sub-harmonic synchrony with the partners’ speed. However, different pairs of monkeys synchronized differently and reached different speeds, and the monkeys synchronized their movements the most when they could both see and hear their partner.

The researchers note that this behavior cannot have been learnt by the monkeys during the experiment, as previous research has shown that it is extremely difficult for monkeys to learn intentional synchronization.

They add: “The reasons why the monkeys showed behavioral synchronization are not clear. It may be a vital aspect of other socially adaptive behavior, important for survival in the wild.”

From sciencedaily.com

11:41pm  |   URL: http://tmblr.co/Z8EaJxcyfY_-
(Notes: 6)
  
Filed under: primate monkey macaque animal science primatology anthropology evolution 
October 22, 2012
For those of you interested in evolutionary anthropology, this is a really interesting show, being broadcast right this second on BBCHD in the UK. If you're missing it, give it a watch when it becomes available on BBC iPlayer. It is the first of 3 shows.

9:33pm  |   URL: http://tmblr.co/Z8EaJxVnS1Df
(Notes: 1)
  
Filed under: BBC UK Anthropology Science Evolution Primate Ape 
October 16, 2012
Like Humans, Monkeys Can Make Irrational Decisions When Making Choices

When making decisions about the value of an assortment of different objects, people approximate an average overall value, which though frequently useful can lead to apparently irrational decision-making. A new study published Oct 3 in PLOS ONE by Jerald Kralik and colleagues at Dartmouth College shows for the first time that non-human primates also make similar ‘irrational’ choices based on approximation.

In the study, researchers found that rhesus monkeys preferred a highly-valued food item (a fruit) alone to the identical item paired with a food of positive but lower value (fruit and a vegetable).

The researchers suggest that this behavior is similar to what has been seen in previous studies with humans, where participants rated a 24-piece dinnerware set more highly than one with the same 24 pieces, plus 16 more pieces of which nine were broken.

According to the authors, decision-making processes in humans and other primates have evolved towards reducing the complexity in choices between large groups of assorted items, which may result in such irrational choices.

“People often judge a group — of valuables, of foods, of other people — by its average rather than by the sum of its parts. Our study shows that monkeys appear to do the same thing, which suggests that both monkeys and people inherited a particular way of simplifying the world around us, making choices easier, sometimes at the expense of ‘rationality’” says Kralik.

From sciencedaily.com

6:19pm  |   URL: http://tmblr.co/Z8EaJxVPd3FT
(Notes: 4)
  
Filed under: Animal Science Anthropology Primate Monkey Human Rhesus Monkey Evolution 
September 20, 2012
Apes Enjoy Slapstick Humour (The Origins Of Laughter)

Non-human primates may enjoy watching someone else trip on a banana peel, according to new research on laughter, which found that apes might appreciate slapstick humor.

The research also helps to explain the origins of laughter and the social aspects of the behavior.

Robin Dunbar, who co-authored one such study with Guillaume Dezecache, described what non-human primates might be amused by.

“The use of language-based jokes is clearly unique to humans,” Dunbar, a professor of evolutionary psychology at the University of Oxford, told Discovery News. “There is some suggestion that apes ‘play practical jokes’ or laugh at another’s misfortune, such as the banana skin situation, but these are only casual observations.”

“Human laughter derives from the play invitation vocalizations of Old World monkeys and apes, but this is normally confined to juveniles and adolescents; adults don’t play,” he continued.

“In apes, this is identifiably rather closer to human laughter,” Dunbar explained, “and bonobos in particular use laughter a lot in play contexts, even among adults. What seems to have happened is that humans have taken these monkey/ape play vocalizations and tweaked them and increased the frequency of their use.”

Human laughter still has an animalistic quality, in the sense that it involves a series of rapid exhalation-inhalation cycles comparable to other primate sounds; it’s louder than human speech; and, like sneezing, laughter is contagious.


Read More at discovery.com

9:47pm  |   URL: http://tmblr.co/Z8EaJxTljqbQ
(Notes: 16)
  
Filed under: Ape Primate Animal Science Anthropology Evolution Human Laughter Chimp Chimpanzee Bonobo 
August 28, 2012

abnormallyspeaking:

Why are there still chimpanzees? 

Biologist Richard Dawkins clears up a popular misunderstanding of evolution: “If we evolved from chimpanzees, how come there are still chimpanzees?”

(Source: , via fyeahgreatapes)

11:36pm  |   URL: http://tmblr.co/Z8EaJxSKkuvW
(Notes: 22)
  
Filed under: Ape Primate Chimp Chimpanzee Bonobo Gorilla Orangutan Human Evolution Richard Dawkins 
August 17, 2012
neurosciencestuff: New genetic data shows humans and great apes diverged earlier than thought To calculate when a species diverged, researchers look at the average age of members of the species when they give birth and mutation rates. The older the average age, the more time it takes for mutations to cause changes. Insects that produce offspring in a matter of months, for example, can adapt much more quickly to environmental changes than large animals that produce offspring many years after they themselves are born. To find such data for both chimps and gorillas, the research team worked with many groups in Africa that included studies of the animals that totaled 105 gorillas and 226 chimps. They also looked at fossilized excrement that contained DNA data. In so doing they found that the average age of giving birth for female chimps was 25 years old. They then divided the number of mutations found by the average age of birth to get the mutation rate. In so doing, they found it to be slower than humans, which meant that estimates based on it to calculate divergence times were likely off by as much as a million years. The end result of the team’s research indicates that humans and chimps likely diverged some seven to eight million years ago, while the divergence of gorillas (which led to both humans and chimps) came approximately eight to nineteen million years ago. To put the numbers in perspective, humans and Neanderthals split just a half to three quarters of a million years ago.

neurosciencestuff:

New genetic data shows humans and great apes diverged earlier than thought

To calculate when a species diverged, researchers look at the average age of members of the species when they give birth and mutation rates. The older the average age, the more time it takes for mutations to cause changes. Insects that produce offspring in a matter of months, for example, can adapt much more quickly to environmental changes than large animals that produce offspring many years after they themselves are born. To find such data for both chimps and gorillas, the research team worked with many groups in Africa that included studies of the animals that totaled 105 gorillas and 226 chimps. They also looked at fossilized excrement that contained DNA data. In so doing they found that the average age of giving birth for female chimps was 25 years old. They then divided the number of mutations found by the average age of birth to get the mutation rate. In so doing, they found it to be slower than humans, which meant that estimates based on it to calculate divergence times were likely off by as much as a million years.

The end result of the team’s research indicates that humans and chimps likely diverged some seven to eight million years ago, while the divergence of gorillas (which led to both humans and chimps) came approximately eight to nineteen million years ago. To put the numbers in perspective, humans and Neanderthals split just a half to three quarters of a million years ago.

(via fyeahgreatapes)

6:41pm  |   URL: http://tmblr.co/Z8EaJxRc7hJb
(Notes: 73)
  
Filed under: Primate Ape Gorilla Chimp Chimpanzee Genetics Evolution 
May 28, 2012

Here are Darwin’s complete publications, digitised and made available online :)

8:26am  |   URL: http://tmblr.co/Z8EaJxMHfQaA
(Notes: 3)
  
Filed under: Charles Darwin Darwin Evolution Biology Zoology History Science Primate Mammal Bird Reptile