In some species of anglerfish, the males are tiny, with simplified body features, and they live as parasites on the females. This is thought to be an adaptation to save energy, allowing the females to feed on whatever food is available. The males seem to have evolved for one purpose only: to find a female and deliver sperm.
In Oneirodes, the males are free-living but much tinier than the females, and they lack teeth. Males have extremely large nostrils and a powerful sense of smell, which they use to locate females. The females apparently release a special chemical that males can detect and follow. Such special chemicals are called pheromones.
The deep sea may seem remote, but what we send down will eventually cycle back up into our lives. Deep-sea animals are part of a thriving ecosystem. Our trash and chemicals may harm them if we are careless with our waste.
The "fishing rod" growing from the female anglerfish's snout ends in a glowing blob of light. At the tip of this modified fin ray, is a small organ (esca) that contains millions of light-producing bacteria.