The causes of leg pain can be musculoskeletal, neurological, or vascular. Shin splints and stress fractures can result from repetitive sports, such as running. Leg pain can sometimes indicate a serious vascular problems.
Noun. 1. altruism-the quality of unselfish concern for the welfare of others. selflessness. unselfishness-the quality of not putting yourself first but being willing to give your time or money or effort etc. for others; rural people show more devotion and unselfishness than do their urban cousins.
Biological Altruism. First published Tue Jun 3, 2003; substantive revision Sun Jul 21, 2013. In evolutionary biology, an organism is said to behave altruistically when its behaviour benefits other organisms, at a cost to itself. The costs and benefits are measured in terms of reproductive fitness, or expected number of offspring.