Stone tool manufacture has not been observed in free-ranging chimpanzees. has been observed in west african chimpanzee groups. has not been observed in any captive nonhuman primate. is uniquely a human characteristic. is common among free-ranging bonobos.

For this question look at the hydropic diagram water that is heated by the sun evaporates. select the number that represents it.

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.

Can a trait be both polygenic and have multiple alleles? explain why or why not.