If you take 40 pounds of luggage with you on a vacation and you buy 10 pounds of souvenirs for your family (because you're really nice), do those extra souvenirs change the density of your luggage? if the density does change, how does this happen?

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.