Toss a steak on the grill and you may be reenacting an event that helped separate men from apes thousands of years ago.
Cooking, according to a new theory from a Harvard anthropologist, was a key turning point in human evolution, and without it, we would still spend significant chunks of our day chewing heaps of raw foods, BBC News reported.
Humans would need to eat more than 10 pounds of fruits and vegetables a day -- a task which would require six hours of chewing, Harvard Professor Richard Wrangham told BBC News. Cooking, he said, allowed humans to begin eating meat.
"I think cooking is arguably the biggest increase in the quality of the diet in the whole of the history of life," he said.
"Our ancestors most probably dropped food in fire accidentally. They would have found it was delicious and that set us off on a whole new direction," he told BBC News.
When Homo erectus, the first truly "human" of our ancestors, evolved 1.8 million years ago, they had bigger brains and teeth than older species, along with the ability to walk upright and run.
Homo erectus also had smaller guts.
"Cooking made our guts smaller," Wrangham told BBC News. "Once we cooked our food, we didn't need big guts. They're costly in terms of energy. Individuals that were born with small guts were able to save energy, have more babies and survive better."
Cooking also allowed humans to spend more energy on thinking than on digestion, Professor Peter Wheeler from Liverpool John Moores University told BBC News.