The behavioral mechanism of sperm thermotaxis has been so far only investigated in human spermatozoa. In the case of mammals, it appears to be done by chemotaxis, thermotaxis and rheotaxis. Blocking both pathways fully inhibits sperm thermotaxis. The sperm follows temperature gradients (thermotaxis) and chemical gradients (chemotaxis) to locate the ovum. Thermotaxis is movement along a gradient of temperature. Mammalian sperm thermotaxis was, hitherto, demonstrated in three species&colon; humans, rabbits, and mice.