Archive for the ‘chimpanzee’ Category

 

Too bad chimpanzees can’t buy sports cars. New research says it’s not just humans who go through midlife crises: Chimps and orangutans also experience a dip in happiness around the middle of their lives.

“There may be different things going on at the surface, but underneath it all, there’s something common in all three species that’s leading to this,” said study leader Alexander Weiss, a primate psychologist at the University of Edinburgh in Scotland.

The study team asked longtime caretakers of more than 500 chimpanzees and orangutans at zoos in five countries to fill out a questionnaire about the well-being of each animal they work with, including overall mood, how much the animals seemed to enjoy social interactions, and how successful they were in achieving goals (such as obtaining a desired item or spot within their enclosure).

The survey even asked the humans to imagine themselves as the animal and rate how happy they’d be.

When Weiss’s team plotted the results on a graph, they saw a familiar curve, bottoming out in the middle of the animals’ lives and rising again in old age. It’s the same U-shape that has shown up in several studies about age and happiness in people.

“When you look at worldwide data, you see this U-shape,” said National Geographic Fellow Dan Buettner, author of Thrive: Finding Happiness the Blue Zones Way.

“It’s different for every country, but it’s usually somewhere between age 45 and 55 that you hit the bottom of the curve, and it continues to go up with age. You see centenarians in good health reporting higher well-being than teenagers.”

(Take Buettner’s True Happiness Test.)

Social and economic hypotheses may partly explain this happiness curve in human lifetimes: Maybe it’s tied to adjusting expectations, abandoning regret, or just getting more stuff as we grow older. But Weiss suspects there may be something more primal going on.

“We’re saying, take a step back and look at the big picture: Is there any evidence that there’s an evolutionary basis underlying this?” said Weiss, whose study was published today in the journal Proceedings of the National Academy of Sciences.

“Knowing that a similar phenomenon exists in human and nonhuman primates opens up the realm of possible explanations.”

Although the stereotype of a midlife crisis is generally negative—feelings of depression or discontentment with one’s life and where it’s headed—Weiss believes such ennui may have an evolutionary upside.

By the middle of one’s life, humans and apes often have access to more resources than when they were younger, which could make it easier to achieve goals. Feelings of discontentment may be nature’s way of motivating us to “strike while the iron is hot,” said Weiss.

“It may feel lousy, but your brain could be tricking you into improving your circumstances and situation, signaling you to get up and really start pushing while you’re absolutely at your prime,” he said. “And I think that’s a really powerful and positive message.”

Knowing that a midlife dip in happiness is a natural—and temporary—part of life could make it easier for humans to cope with the experience, Weiss said. It could also help caretakers improve captive apes’ quality of life, by identifying ages at which the animals might benefit from extra attention or enrichment.

(See pictures of places where people are happiest.)

“I don’t think this totally subsumes other explanations for age-related changes in happiness, but it adds another layer,” Weiss said.

Weiss has previously studied the correlation between personality and happiness in both chimpanzees and humans, and plans to look next at the impact of factors like sex and social groupings.

“I hope this raises awareness of all that we can learn by looking at our closest living animal relatives.”

http://news.nationalgeographic.com/news/2012/11/121119-apes-happiness-midlife-crises-science-animals/

 

Humans share about 99 percent of our genomes with chimpanzees. Now, research finds we share something else: gut bacteria.

The bacterial colonies that populate the chimpanzee intestinal tract are mirror images of those found in the human gut, researchers report today (Nov. 13) in the journal Nature Communications. The findings suggest gut bacteria patterns evolved before chimps and humans split and went their evolutionarily separate ways.

Human gut bacteria are crucial to health, with infants relying on healthy microbe populations to influence the developing immune system. Problems with microbe populations may also contribute to obesity and inflammatory bowel diseases. 

Three intestinal ecosystems

In 2011, researchers learned that everyone’s gut bacteria fall into one of three different types, almost analogous to blood types. In each type, certain bacteria dominate. These types weren’t linked to any personal characteristics such as geographic area, age or gender. Researchers dubbed these distinct bacterial ecosystems “enterotypes.” (“Entero” means gut or intestine.)

“No one really knows why these three enterotypes exist,” said study researcher Andrew Moeller, a doctoral student at Yale University.

Along with his adviser Howard Ochman and their colleagues, Moeller want to understand how these enterotypes arose. They could be distinctly human, he told LiveScience, which would suggest they arose relatively recently, perhaps in response to the development of agriculture. Or they could be ancient, shared among our closest primate relatives.

The researchers analyzed gut bacteria samples from 35 chimpanzees from Gombe Stream National Park in Tanzania. The chimpanzees were all in the subspecies Pan troglodytes schweinfurthii, the eastern chimpanzee, which arose approximately the same time as Homo sapiens.

Shared bacteria

The researchers found that, just like humans, chimps’ guts harbor one of three distinct types of bacterial colonies. Even more intriguingly, these enterotypes matched humans’ precisely. In type 1, for example, both humans and chimps show a predominance of Bacteroides, Faecalibacterium and Parabacteroides.

There were some differences. For example, in humans and chimps, enterotype 2 is marked by an overabundance of bacteria called Lachnospiraceae. In humans, the bacteria Prevotellae is also prevalent in type 2. In chimps, Prevotellae appears in significant numbers in all three enterotypes, perhaps because it is associated with a high-carbohydrate diet.

Other differences could help explain certain human health issues. By comparing human and chimpanzee gut bacteria, the researchers found many of the bacteria present only in humans are linked to diseases such as inflammatory bowel diseases, conditions that cause pain, diarrhea and vomiting.

Seven of the chimps in the study were tested repeatedly over eight years, and their gut microbes were found to change from type to type over that time period. No one has ever tested humans for changes over a period longer than two weeks, Moeller said, but the results suggest our enterotypes may shift over time, too.

Our shared history

The similarities between chimp and human colonies suggest enterotypes predate our species, which in turn suggests that none of the three ecosystems are better than the others, Moeller said. [Gallery: Tiny, Nasty Bugs That Make Us Sick]

“Before we found this in chimpanzees, there was a possibility that enterotypes were a product of modernization, which could mean they have some negative effects on health,” he said. “I don’t think there’s any reason to think one enterotype is going to have an effect on health that’s going to be better” than the others.

Moeller and his colleagues are now examining gorilla fecal samples to find out where they stand as slightly more distant primate relatives to humans.

“The next step is to try to find out the processes and mechanisms responsible for producing these three community states,” Moeller said, “which is kind of a lofty goal, but I think more sampling will actually reveal why these communities exist.”

http://www.livescience.com/24738-chimp-human-gut-bacteria-identical.html