Some think so.
A series of 4 scientific papers shows evidence of an expanding variety of plant foods, written into the enamel of fossil teeth.
“What we have is chemical information on what our ancestors ate, which in simpler terms is like a piece of food item stuck between their teeth and preserved for millions of years,” said Alemseged.
These papers represent the first time that scientists have analyzed carbon isotope data from all early human species for which significant samples exist: 175 specimens representing 11 species, ranging from 4.4 to 1.3 million years in age. The results show that prior to 3.5 million years ago, early humans ate almost exclusively C3 plants. But starting about 3.5 million years ago, early humans acquired the taste for C4/CAM plants as well, even though their environments seemed to be broadly similar to their ancestors’. The later genus Homo, including modern-day Homo sapiens, continues the trend of eating a mixture of C3 and C4/CAM plants—in fact, people who enjoy mashed potatoes with corn are practicing a 3.5 million-year-old habit.
Apparently, giraffes, horses, and monkeys continued to munch whatever.
So that guy in the next cube who bores you with his account of finding the perfect arugula is still someone who bores you, and his predecessor was probably boring people a million years ago. Yawn.