Research from University College London has shown that male flies that are genetically programmed to produce only female offspring compensate for their low sperm count by growing larger testes. Male ...

After a decade of research, Howard Hughes Medical Institute scientists have succeeded in reprogramming adult stem cells from the testes of male mice into functional blood vessels and contractile ...

Easily accessed and plentiful, adult stem cells found in a male patient's testicles might someday be used to create a wide range of tissue types to help him fight disease -- getting around the need ...

It may only be half the size of a human finger, but this cricket is hiding a big secret: it has the largest testicles in relation to its body weight in the world. Scientists have discovered that the ...