Animals don’t only need to look for and attract food: Bioluminescence can also play a part in attracting mates. There are different ways that animals use glowing to attract mates.
1:Flashing lights – female fireflies are attracted to flasher males. The bright flashes generated by the male fireflies are signals designed to catch the eye of interested females. If she feels one of the males, the female flashes back in response (1). Different species of fireflies have different duration and rate of flashing. Females are only attracted to the flashing pattern of males of their own species (2).
2:Moving their body
One example of a species that uses its body are fireworms that live on the floor of the ocean. With the onset of the full moon they move to the open water where the females of some species, like Odontosyllis enopla, use bioluminescence to attract males while moving round in circles (1).
There are also Anglerfish that have a pole-like structure on the top of their head that glows at the very end. This glowing is used to communicate between the male and female in order to mate (1).
3:Vomit glowing mucus
In a very bizarre method of attracting mates, some males crustaceans actually vomit up a bioluminescent mucus to attract females. Their display looks like strings of tiny, glowing pearls. Some light up in a zigzag pattern, others appear in a horizontal form upward toward the surface. The glowing goes for a few seconds, then fades to black like underwater ghosts. But these are blobs of mucus vomited up by crustaceans called ostracods. Males use the vomit to impress potential mates.(3) To see a cool video of this behaviour, click on the following link: https://www.youtube.com/watch?v=9HXXQBz6Vv0&feature=emb_imp_woyt
An underwater image of ostracods glowing courtship displays.