mutation dated the Last Glacial Maximum (20,000 years ago). Average cranial capacity among modern male human populations varies in the range of 1,200 to 1,450 cm3. Larger cranial volumes are associated with cooler climatic regions, with the largest averages being found in populations of Siberia and the Arctic. Humans living in Northern Asia and the Arctic have evolved the ability to develop thick layers of fat on their faces to keep warm. Moreover, the Inuit tend to have flat and broad faces, an adaptation that reduces the likelihood of frostbites. Both Neanderthal and Cro-Magnons had somewhat larger cranial volumes on average than modern Europeans, suggesting the relaxation of selection pressures for larger brain volume after the end of the LGM. Australian Aboriginals living in the Central Desert, where the temperature can drop below freezing at night, have evolved the ability to reduce their core temperatures without shivering. Holocene (12,000 years ago to present) Neolithic or New Stone Age The advent of agriculture has played a key role in the evolutionary history of humanity. Early farming communities benefited from new and comparatively stable sources of food, but were also exposed to new and initially devastating diseases such as tuberculosis, measles, and smallpox. Eventually, genetic resistance to such diseases evolved and humans living today are descendants of those who survived the agricultural revolution and reproduced. The pioneers of agriculture faced tooth cavities, protein deficiency and general malnutrition, resulting in shorter statures. Diseases are one of the strongest forces of evolution acting on Homo sapiens. As this species migrated throughout Africa and began colonizing new lands outside the continent around 100,000 years ago, they came into contact with and helped spread a variety of pathogens with deadly consequences. In addition, the dawn of agriculture led to the rise of major disease outbreaks. Malaria is the oldest known of human contagions, traced to West Africa around 100,000 years ago, before humans began migrating out of the continent. Malarial infections surged around 10,000 years ago, raising the selective pressures upon the affected populations, leading to the evolution of resistance. A study by anthropologists John Hawks, Henry Harpending, Gregory Cochran, and colleagues suggests that human evolution has sped up significantly since the beginning of the Holocene, at an estimated pace of around 100 times faster than during the Paleolithic, primarily in the farming populations of Eurasia. Thus, humans living in the twenty-first century are more different