Life is complex. Just a slight change in the population of one species will have a substantial change on the biotic and abiotic factors of that species' environment. In this video, Mr. Andersen explains the effects removing wolves from...

Cocos Island, a remote volcanic summit in the middle of the Pacific Ocean, serves as a beacon for hungry predators, including thousands of hammerhead sharks that travel here each year in search of prey. This video segment from NOVA:...