If you remove a fruit fly’s front legs, which contain a number of sensory organs, then it will mate with both male and female fruit flies as well as other fly species. – WTF Fun Facts
Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3823234/
fruit fly
Fun Animal Fact – Sperm Size
A mouse’s sperm is much, much larger than an elephant’s sperm. However, the fruit fly produces the longest sperm known to science. – WTF Fun Facts
Source: https://gizmodo.com/this-is-why-a-mouses-sperm-is-longer-than-an-elephants-1743378063