How can fossil identification be difficult?
O It is rare to find a complete set of fossils.
O It is hard to tell animals apart based on their fossils.
O It is hard to tell different types of fossil apart based on looks
O All fossils have the same color.

Which of the following best describes the expensive tissue hypothesis? brains require more energy, so the gut had to be reduced, and larger brains and tool use led to higher quality diets. increasing body size means that homo neanderthalensis had to include more fat in its diet. brains require more energy, so the gut had to be reduced as brains got bigger. brains require more fat, so the gastrointestinal viscera (gut) had to expand, and hands were needed to acquire more food.