How does mutualism compare with commensalism? In both mutualism and commensalism, all organisms engage in active competition with each other, often at the other's expense.
In both mutualism and commensalism, there are benefits to one organism whereas the other organism may or may not benefit.
In mutualism, both organisms benefit, whereas commensalism benefits one organism without benefiting or harming the other.
In mutualism, one organism is unharmed while the other is harmed, whereas both organisms are harmed in commensalism.