There are over 1,100 species of bats worldwide, with at least 121 species found in Guyana and 86 found within the Iwokrama forest. They are found on every continent except for Antarctica, feed at every level of the ecosystem and are the only, true, flying mammal. The smallest bat measures around 3 cm in length with wingspans of 15 cm, whilst the largest measures around 15 cm with wingspans about 1.5 m in length.