Humans Live Longer Than Other Mammals: Study

Humans and other primates burn 50 percent fewer calories each day than other mammals, shows a new study.

The study suggests that these remarkably slow metabolisms explain why humans and other primates grow up so slowly and live such long lives.

At Least Two Ancient Global Warming Events Responsible for Shrinking Body Size of Mammals
The body size of mammals shrunk significantly during two ancient global warming events, a new study reveals.

The study also reports that primates in zoos expend as much energy as those in the wild, suggesting that physical activity may have less of an impact on daily energy expenditure than is often thought.

An international team of scientists working with primates in zoos, sanctuaries, and in the wild examined daily energy expenditure in 17 primate species, from gorillas to mouse lemurs, to test whether primates' slow pace of life results from a slow metabolism.

Using a safe and non-invasive technique known as "doubly labeled water," which tracks the body's production of carbon dioxide, the researchers measured the number of calories that primates burned over a 10 day period.

Scientists Discover New Antiviral Response in Mammals
In mammals, scientists have identified a novel antiviral response. Many viral infections are nipped in the bud by the innate immune response.

Combining these measurements with similar data from other studies, the team compared daily energy expenditure among primates to that of other mammals.

"Humans, chimpanzees, baboons, and other primates expend only half the calories we'd expect for a mammal. To put that in perspective, a human - even someone with a very physically active lifestyle - would need to run a marathon each day just to approach the average daily energy expenditure of a mammal their size," lead author of the study Herman Pontzer, an anthropologist at Hunter College in New York, said.

Genetic Process may Solve Puzzle Behind Evolution of Sex Determination in Mammals
A genetic process found in many species of rodents could have a significant influence on our assumptions about sex determination and the pace of evolution, a new study reveals.

This dramatic reduction in metabolic rate, previously unknown for primates, accounts for their slow pace of life.

All organisms need energy to grow and reproduce, and energy expenditure can also contribute to aging. The slow rates of growth, reproduction, and aging among primates match their slow rate of energy expenditure, indicating that evolution has acted on metabolic rate to shape primates' distinctly slow lives.

Mammals Able to Choose Offspring�s Sex
A new study that tracked three generations of nearly 2,300 animals from the San Diego Zoo, found that mammals portray an ability to select the gender of their offspring.

The study was published in the Proceedings of the National Academy of Sciences.

Source-ANI