What is the source of carbon for the organisms of food chains?

Which of the following will not cause mass extinction? a. drastic change is weather b. geological change c. both a and b d. none of the above

What causes darkening of the skin as melanin production increases

African penguins, which inhabit the coasts of southern africa, were classified as an endangered species in 2010. two significant threats to their survival are ecosystem damage from oil spills and overfishing by humans. overfishing depletes the food supply of african penguins. the best method to reduce the threat of overfishing would be to . the risk of oil spills could be reduced by increasing the use of , which should oil consumption. if an oil spill does occur, could be used to remove the oil so the ecosystem may more quickly recover.