"runner's high" occurs when prolonged, intense athletic activity causes the release of the brain's natural painkiller.

What do animals wth echolocation have in common other than echolocation

Study the diagram of a desert food chain . what would most likely happen if the kangaroo rats were killed off and removed from the food chain ?

Write a paragraph explaining how energy flows through an ecosystem using the following terms: energy pyramid, trophic level, producer, primary consumer, decomposer, sun, secondary consumer, and tertiary consumer. .