the first recorded human outbreak of ebola virus was in 1976, but the source of the virus is still unknown. recent tests have shown that some species of fruit bats collected during ebola outbreaks show the bats have the virus, but do not show any signs of it. further studies also show that ebola can reproduce in fruit bats and other bats in the 'tadarida' genus. this could mean that the bats are the source of the virus. the marburg virus, which is related to ebola, has also been found in fruit bats in uganda.