Utilizing craniometrics to examine the morphological changes to Homo with the advent of processing food by cooking

This thesis examines the extent to which the development of cooking by early humans contributed to morphological changes in the human skull, hypothesizing that the cooking of food by early humans had a direct effect on human evolution, leading to smaller face shape, larger body size, and larger brain development, which can be measured in the skull using craniometrics. Beginning with Homo erectus around 1 million years ago, early humans began cooking food. By beginning the process of physical and chemical breakdown of food prior to consumption, humans were able to better access calories and nutrients already found in their food and maximize their use in the body. This shift in eating method allowed for the overall size of the digestive tract to shrink, allowing for excess nutrients and calories to be redirected to the brain, causing total brain size to dramatically increase. The decreased emphasis on chewing also allowed muscles of the face associated with mastication to shrink, thus influencing the bone structure of the skull.

Established craniometric points of the skull were used to measure morphological changes in seven species; Paranthropus boisei, Homo habilis, Homo erectus, Homo heidelbergensis, Homo neanderthalensis, H. sapiens idaltu, and modern Homo sapiens. Odontometrics for each individual were also taken to determine whether cooking affected overall tooth size as well as skull morphology. Results of the study were supportive of the hypothesis. Several craniometric measurements found at muscle attachment site used for mastication indicate high levels of dissimilarity between individuals of different species.