system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do bugs seem to fly in circles around one when out hiking, particularly around the head?
gpt
Generally, they are either attracted to the carbon dioxide you are exhaling or the body heat you are giving off. For flies, it's the CO2, mosquitoes seek body heat. And the head is usually the hottest part of your body, and it's usually exposed, especially in the type of weather that mosquitoes are an issue.