University of Manchester scientists have discovered significant concentrations of microplastics in the male reproductive ...

Fish anatomy reveals that these unique aquatic creatures reproduce sexually by producing and fertilizing eggs and sperm.

DESCRIPTION: Freshwater mussels are bivalve mollusks that have a two- valved hard shell, a soft body with respiratory, digestive and reproductive organs, and a muscular ... must attach to the gills of ...

A parasitic fish called a lamprey sometimes attaches itself near a male shark’s claspers, or reproductive organs. This can make it more difficult for scientists to identify an individual’s sex.