PIP: In many hunter gatherer societies, food taboos dictate the diets of females. These taboos often happen during their most critical reproductive times in their life, e.g., pregnancy. Among some subarctic Athapaskan societies, females at menarche cannot eat fresh meat. They, like other hunter gatherer societies, also restrict fresh meat consumption for menstruating women. Young women of the Aranda society in Australia cannot eat protein rich foods, e.g., lizards, until they have a child. Australian aboriginal societies restrict protein and fat foods for pregnant and lactating women. Even though the literature shows that the undernourished are inclined to reach menarche at a later age than those who eat a well balanced diet, it does not clearly establish whether differences in age at menarche significantly affect overall fertility. Research done on many different under or marginally nourished populations indicates that maternal nutritional health influences birth spacing significantly. Specifically, undernutrition causes longer postpartum amenorrhea. Therefore, lower fertility rates follow longer birth intervals. Research shows that poor maternal nutritional health does not prevent the fetus from surviving and growing. Yet mothers who do not consume many calories often have low birth weight infants. These infants are at high risk of dying because they have little to no fat reserves and they consume inadequate amounts of nutrition since the mothers cannot make insufficient amounts of milk. Since contemporary research shows that maternal nutritional health does effect fertility and infant mortality, food taboos do have the ability to influence population size. More research is needed to understand the factors that influenced the reproductive rates of past hunter-gatherer societies, so anthropologists can identify the demographically significant changes which sedentism and agriculture caused 10,000 years ago.