Physiognomy

[Nobel]

I deem it unnecessary to develop such self-ability, but what about you? Do you depend on it and on what instances would it be practically useful?

 

[YowYan]

For a word You probably learned earlier today; Shouldn't You add the meaning of it for starters

 

[ChicagoJhawk]

Physiognomy deez nuts

 

[Callypigia]

It's evolution. The ability to discern a person's character by their facial expressions is a primary form of communication. Non-verbal communication is crucial for empathizing with others. It also can offer protection from people with ill intent. Dogs have adapted to not only read human facial expression, but respond to it with their own facial expression (a trait that they do not use with other dogs). Many studies have been done, and continue to be conducted on how modern technology through social media and cellphones is slowly removing this ability.

If you're using the other definition (using facial characteristics to determine ethnic origins) to start some race discussion the answer is still the same. It's evolution. Species on this planet show a preference to aesthetically similar beings. This is to help ensure passing of homogeneous genetic lines for survival of the particular species' traits. Just as an anecdote I've seen this occur with puppies and chickens; they will bully the puppies/chicks that look different.