Cooking may have given humans edge over apes by reducing energy cost of eating.

Byline: ANI

Washington, February 14 (ANI): A study presented at the American Association for the Advancement of Science's annual meeting in Chicago this week suggested that cooking gave humans an evolutionary edge over apes in terms of growth.

The researchers presenting the study said that cooking, a "signature feature" of the human diet, might have originated in the extinct species Homo erectus 1.8 million years ago.

"The hallmark of dietary evolution is our flexibility and plasticity. What made humans humans is the ability to find or make a meal in the environment," National Geographic quoted William Leonard, an anthropologist at Northwestern University who was not involved in the new research, as saying.

H. erectus had a large brain and body size, and many believe that the species' hunter-gatherer lifestyle, associated with more cooked meat, fuelled its growth.

Scientists, however, have been unclear as to why they initially put food to fire.

Suggesting a reason for that, Harvard University biological anthropologist Richard Wrangham said that the earlier chefs might have started cooking because it decreases the energy cost of eating.

For primates, including humans, "energy is absolutely critical, and (it's) what natural selection is constantly trying to maximize," Wrangham said.

The researcher said that cooking makes starchy things gelatinous, breaks up proteins, and softens rock-hard edibles.

According to Wrangham, such textural and chemical changes make foods easier to eat and digest.

The researcher also said that the shift to cooking was reflected in modern human anatomy, as human jaws are considerably smaller and less able to bite into hard foods.

He further said that human gut is not set up for processing raw items as effectively as cooked food.

Leonard said that what set humans apart from apes was a need for a high-quality, high-calorie diet, combined with a drive to be active over a large area.

He said that humans' "remarkable ability" to find and process many types of food is what probably led to the tremendous diversity of healthy diets across the globe.

The researcher, however, called humans "a victim of evolutionary successes" because people these days consume many calories, but don't get nearly as much exercise as early humans. (ANI)

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