As scientists have developed more productive crop varieties, farmers have switched from growing many traditional varieties to new high-yield varieties. For example, in Peru, the Indians once grew 500 native varieties of potatoes. That number has been reduced to about twenty major potato varieties, worldwide. Why is it potentially dangerous to reduce the number of crop species in potatoes? A) It reduces the variety of crops available for human diets. Eliminate B) It requires a larger investment than small farmers can make. C) It makes the overall crop more susceptible to pests or disease. D) It could reduce or cause the extinction of some predatory insects.

Monarch butterflies have brightly colored orange wings with black patterns on them, making them easily visible to birds that eat butterflies and moths, yet birds rarely eat the monarchs. likewise, the monarch caterpillars are brightly striped yellow and white and black, and they also are rarely eaten by birds, although some wasps will attack them and feed them to their young. what can be inferred from these observations? monarchs must threaten and attack birds, but not wasps. monarchs have a way of discouraging bird predation that does not involve hiding. monarchs’ wings are so colorful that most birds must find them difficult to eat. monarchs lay more eggs than other less conspicuous butterflies.