Figure 43.6: A Food Web in the Grasslands of Yellowstone National Park The arrows point from resource to consumer. Even this highly simplified food web is complex. Primary consumers eat plant material (blue arrows). Secondary and tertiary consumers are carnivores that kill and eat live animals (red arrows). Omnivores such as grizzly bears, coyotes, and ravens eat both plant and animal tissues; ravens and grizzlies also eat carrion (flesh of dead animals that they did not kill; dashed red arrows).