Types of sperm motility in different species

There are large variations in sperm motility both between species and within a given species—depending on the surroundings (see [74] for a 

The rotation of spermatozoa around their long axis is not restricted to human spermatozoa the spermatozoa of all species appear to do so [75], In each species the spermatozoa rotate both clockwise and counterclockwise, but the proportion of the clockwise-rotating and counterclockwise-rotating populations varies between species. Interestingly, the majority of sea urchin and starfish spermatozoa rotate clockwise (viewed from the anterior end), and their flagella form right-handed waves. In contrast, the majority of mammalian spermatozoa rotate counterclockwise and their flagella form left-handed waves which, in the case of human and bull spermatozoa, look like a three-dimensional left-handed helicoid [75]. 

A given spermatozoon can change its direction of rotation, indicating that the three-dimensional geometry of flagellar movement can change 

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