Definition
A methanogen is a microorganism that produces methane as a metabolic byproduct. Think of them as tiny methane factories! 🏭 They belong to the domain Archaea and thrive in anaerobic (oxygen-free) environments. You'll find them in swamps, digestive tracts of animals, and even sewage treatment plants! They play a crucial role in the carbon cycle. Their methane production can be both beneficial (biogas) and problematic (greenhouse gas).