Richard Wrangham a professor of biological anthropology at Harvard and the author of “Catching
Fire: How Cooking Made Us Human” was interviewed on NPR. He worked with Jane Goodall, and is director of the Kibale Chimpanzee Project in Uganda. According to Wrangham, great apes prefer cooked food to raw food or they have no preference. They prefer cooked meat to the raw meat that they occasionally form hunting parties to obtain, but are hampered by not controlling fire. Great apes, when given a choice, never prefer raw food to cooked food. Chimps will go into areas of wildfires and eat foods that they would never eat raw. Meat (at least wild meat) is tough when raw, but is much more easily assimilated when cooked.
Cooked food increases the proportion of nutrients that you actually digest. This was not widely appreciated for many years because scientists sampled the food going into the mouth then compared it to fecal output. But fecal digestibility does not really look at assimilation. We can only assimilate proteins in the small intestine, not the large intestine.