Leg pain from degenerative disc disease can also result if the nerve root is compressed. This happens because as the disc degenerates it shrinks and moves, and as a result, there is not as much room for the nerve roots. This is also known as foraminal stenosis. Leg pain from a compressed and inflamed nerve root is typically shooting and electric.
Altruistic behaviour is therefore the opposite of egoistic behaviour. It involves intention to help others when used of human behaviour, but the fact that some animal behaviour is judged to be altruistic indicates that there are two possible bases to a definition: intentionality, and behavioural effects.
In biology, altruism refers to behaviour by an individual that increases the fitness of another individual while decreasing the fitness of the actor. Altruism in this sense is different from the philosophical concept of altruism, in which an action would only be called altruistic if it was done with the conscious intention of helping another. In the behavioural sense, there is no such requirement. As such, it is not evaluated in moral termsâit is the consequences of an action for reproductive fitness that determine whether the action is considered altruistic, not the intentions, if any, with which the action is performed.