What is the reason for the darker fur on the tail, ears, nose, and legs of a Siamese cat?

Question

(a) Incomplete dominance

(b) the interaction of the environment with gene expression

(c) quantitative inheritance

(d) epistasis

(e) none of these

I put (a), but I'm kinda confused. Please & thank you!

Answer 1

I guess when someone started the breed they bred them to look that way.  Did you know that they are born show white and they start to darken a bit in the first few days.  Not totally because it is gradual but you can see the shading start.  I love Siameses.  A lot of people don't but I have had them in the past and mine were lovely cats.

Answer 2

Apparently, the dark fur grows only if the part of the body is cold.

Of course it is a gene that induces this feature.

The description of the process:

http://en.wikipedia.org/wiki/Siamese_(ca...

A description in Animal Genetics, very technical,

see bottom of summary:

http://www.blackwell-synergy.com/doi/ful...

My best answer is like you (a).

Answer 3

MathJakk is right about the cold. However, I think that it makes the best answer "b".