Early Human Evolution

If it's so unhealthy and unnatural for humans to eat meat, why did our ancestors turn to animal flesh for sustenance?

During most of our evolutionary history, we were largely vegetarian.¹² You could probably figure this out by noting that all the great apes, our closest living relatives, are also predominantly herbivorous. Like apes, our bodies evolved to eat fruits, nuts, and vegetables.¹³

Harvard anthropologist Richard Wrangham and his colleagues first explained that root vegetables—and the ability to cook them—prompted the evolution of large brains, smaller teeth, modern limb proportions, and even male-female bonding.¹⁴ Plant foods like potatoes made up the bulk of our ancestors' diet and spurred our advancement as a species.

The addition of modest amounts of meat to the early human diet came with the invention of fire, which allowed us to eat meat without being killed by it (usually). This practice did not turn our ancestors into carnivores but rather supplemented their traditional plant foods and allowed early humans to survive in periods when plant foods were unavailable.

Anthropologists believe that early humans started to consume small amounts of meat when climate changes made plant foods scarce. During this period, starting a little over a million years ago, humans began to hunt animals for sustenance in the ever-changing landscapes they encountered during their migrations.¹⁵

Modern Humans

Fully modern human beings (Homo sapiens) evolved about 150,000 years ago in Africa and soon spread across the globe.¹⁶ With the advent of agriculture, about 23,000 years ago, humans began to gather seeds and cultivate crops to provide a more consistent food supply.¹⁷ Our ancestors occasionally killed animals for their flesh, but they still received most of their nutrition from plant sources. Until recently, only the wealthiest people could afford to feed, raise, and slaughter animals for their flesh. Consequently, prior to the 20^th century, only the rich died from diseases like heart disease, obesity, and strokes.

Read more.