Img 1 Adult fleas don’t fly, they jump.
Fleas do not fly. They don’t possess the wings needed for flight. Most parasites of mammals and birds lack functional wings and can’t fly (e.g. fleas, ticks, bedbugs, and lice).
Fleas & Flight
Flea Ancestors Flew
Fleas have parasitized mammals for 60 million years. While fleas don’t fly, it’s believed their ancestors did. They’re thought to descend from two-winged insects, specifically a species similar to scorpionflies. When early “pre-fleas” adopted a parasitic way of life, they began living within the burrows of their hosts. As a result, their wings and ability to fly became a hindrance. In time they were lost.
Adaptations for Jumping
The remarkable jumping ability of fleas has been described as “flying” with their legs. Though fleas have lost their wings during the course of evolution, many of the physical flight structures have been retained, modified, and incorporated into their jumping mechanism.
Most notably, fleas possess a pleural arch. This structure is homologous to the wing hinge ligament of flying insects. The pleural arch contains a highly elastic rubber-like protein called resilin. The resilin allows fleas to store and quickly release the energy needed to make their incredible jumps.