Smallest

• The smallest species of bat is the Miniopterus aelleni, which weighs 5g or 1.7 oz. It was discovered by the Natural History Museum in Geneva, Switzerland in the summer of 2009.
  
  

Diet

• A majority of bats eat insects, but some will eat fruit, flower nectar, fish, frogs and blood. Two species are known to prey on other bats.
  
  

Oldest

• The oldest known bat species, Onychonycteris finneryi, lived 52.5 million years ago. The fossils were discovered in a quarry in Wyoming in August, 2003.
  
  

Lifesavers

• Vampire bats have an anticoagulant in their saliva. According to the American Heart Association's year-end report in 2003, scientists are trying to come up with a synthetic version in order to help patients with blood clotting problems.
  
  

Altruism

• According to the Humane Society of the United States, adult female bats will willingly adopt orphaned baby bats. According to the documentary, "Trials of Life: Friends and Rivals" (Sir David Attenborough, 1990), vampire bats will share blood with hungry bats in their colony.