We are all too familiar with these birds of prey. They are the ones we see hovering above an animal that has been killed by its predator, and after its killers have left, they swoop down to finish the meal. We might think that vultures are gross because they like to finish up rotting dead meat. But, in truth, vultures help the environment at lot because although they are scavengers, they are also garbage keepers who make sure the environment is clean...