Appearance

• Many deep sea fish have incredibly large mouths in relation to their overall body size. This is thought to be because food is so scarce that they need to be able to swallow as much as they can when they find food.
  
  

Food

• Scientists are still unclear as to the exact diets of many deep sea creatures. Most deep sea fish are carnivorous, hunting and scavenging.
  
  

Types

• Some of the most common types of deep sea fish include lanternfish, anglerfish, viperfish, ogrefish, orange roughy and the umbrellamouth gulper.
  
  

Sight

• Many deep sea fish are able to produce blue or red light, called bioluminescence, from chemicals in their bodies. This light is usually concentrated in one spot.
  
  

Controversy

• According to BBC News, many deep sea species take nearly 20 years to become sexually mature. It is thought some species are on the verge of extinction because of over-harvesting from trawler fishing.