Like goats, cows are ruminants, which means their stomachs have four chambers, allowing them to chew, digest and regurgitate their food multiple times.
However, the process by which grass and fiber is broken up in the stomachs of cows and other grazing ruminants has a byproduct, methane, a potent greenhouse gas.
As ruminants with multi-chambered stomachs, bison can extract more nutrients from grass and this may help explain why they survived when other grazers such as the wild horses did not.
Guess he has to deal with it every Bovidae and while he doesn't leave much ruminant for the cars passing by, it seems he's able to huff if they get too close.
It is an important fact that rudimentary organs, such as teeth in the upper jaws of whales and ruminants, can often be detected in the embryo, but afterwards wholly disappear.