Since parasites depend on their hosts for survival.

• Position: SCIENCE SCENE - Brief article

Since parasites depend on their hosts for survival, why do they harm them? Parasites strike a middle ground between the benefits gained by reproducing rapidly and the costs to their hosts, according to the 'trade-off hypothesis" put forth by scientists at Emory University, Atlanta. "Parasites have to harm their hosts to replicate and be transmitted but, if they harm their hosts too much, they'll suffer, too. On the other hand, it does not benefit the...