thermotaxis

In the case of mammals, it appears to be done by both chemotaxis and thermotaxis.

M. incognita has been found to be able to move along shallower temperature gradients (0.001C/cm) than any other known organism, an example of thermotaxis.

Research has explored the neural mechanisms responsible for several of the more interesting behaviors shown by C. elegans, including chemotaxis, thermotaxis, mechanotransduction, and male mating behavior.

The temperature gradient in the rabbit oviduct was calculated to be at the order of 0.1 C/cm (Bahat and Eisenbach, 2006), within the range of known thermotaxis systems.

Following the suggestion of Hunter (1998) that this temperature difference might serve as a cue for guiding spermatozoa to the site of fertilization, Bahat et al. (2003) demonstrated that rabbit and human spermatozoa are able to sense small temperature differences and respond to them by thermotaxis.

The findings that mammalian spermatozoa are capable to respond to a chemoattractant gradient by chemotaxis and to a temperature gradient by thermotaxis and that both such gradients are established in the female genital tract raised the possibility that spermatozoa guidance is done by both chemotaxis and thermotaxis.