I think that's backwards.
"The diet of the earliest
hominins was probably somewhat similar to the diet of modern chimpanzees: omnivorous, including large quantities of fruit, leaves, flowers, bark, insects and meat (e.g., Andrews & Martin 1991; Milton 1999; Watts 2008). Tooth morphology and dental microwear studies suggest that the diet of some hominins may have included hard food items such as seeds and nuts, and underground storage organs (USOs) such as roots and tubers (Jolly 1970; Peters & O'Brien 1981; Teaford & Ungar 2000; Luca
et al. 2010)"
The first major evolutionary change in the human diet was the incorporation of meat and marrow from large animals, which occurred by at least 2.6 million years ago.
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