How does a mosquito find an animal or human to bite?

Female mosquitoes are attracted to the gas (carbon dioxide) that humans and other animals breathe out. Mosquitoes can follow a stream of carbon dioxide from as far as 50 feet away. Mosquitoes are also attracted to substances like lactic acid on your skin, which your body produces in greater amounts when exercising. Mosquitoes may also be attracted to certain scents or fragrances and are more attracted to dark colors than light colors.