It is needed by all living things and every living cell to carry out life processes, such as breaking down and building up molecules, and transporting many molecules across cell membranes. The form of energy that living things need for these processes is chemical energy, and it comes from food.
Increased use of antibiotics since the few that are immune will survive and reproduce and will out grow others that arent.
Fluke don't contain bones, while fins do. Flukes go fast while fins steer. Flukes also manage temperature control.
Based on what i know of bats they have echo location to help them navigate were they are going and the echo location helps them to find food.a special feature that they have to help them survive is their hearing do to their lack of eye sight they compensate with unnatural hearing.