Believe it or not, but ducks have a reputation for the unexpected: bizarre and intricate mating anatomy. According to ...

Medically reviewed by Andrea L. Braden, MD Key Takeaways The female reproductive system includes organs that produce hormones like estrogen and progesterone. Ovaries release one mature egg each month ...

The cellular biology of reproduction is often depicted as an epic journey, in which millions of intrepid sperm fight to be the first to claim the ultimate prize: the chance to fertilize the egg, which ...

During mammalian reproduction, millions of sperm undertake a journey that only one will finish. This journey to fertilization has been commonly viewed as a race: a sea of sperm competing to get to the ...

Mercedes Burns has previously received funding from the National Science Foundation. An Asian water dragon hatched from an egg at the Smithsonian National Zoo, and her keepers were shocked. Why? Her ...