The Earth is made up of 75% water. Sources such as oceans, lakes, and rivers have an important role in keeping Earth's surface insulated and warm. What property of water provides this protection?

Tropical rain forests support more species per unit area than any other terrestrial ecosystem. what is one way rain forests are important to the health of the biosphere?

Why did adult crab numbers decline in he ecosystem, even though sea stars were still available?

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.