– How do scientists know that a sea creature is extinct or endangered if they haven’t explored 80% of the sea?

Question

– How do scientists know that a sea creature is extinct or endangered if they haven’t explored 80% of the sea?

In: 2

Answer 1

The world can be divided into “biomes” which share characteristics such as rainfall, temperature, sunlight etc. and most life is suited to one particular biome.

Conditions in the oceans vary massively with depth so a creature living near the surface won’t be found in the unexplored depths of the seas, thus we can conclude that a creature we know about with a declining population is endangered and won’t be found in deeper water.