What are the Limitations of Evolution and Selective Breeding?

Aug 2016
977
US&A
I've been wondering why a lot of domesticated animals aren't even more suitable for life with humans than they are. For example, it seems like many farm animals could've been bred to produce more females than males.



What are the limitations of selective breeding and evolution? Why are some traits modifiable and others not?
 

aggienation

Ad Honorem
Jul 2016
9,745
USA
I've been wondering why a lot of domesticated animals aren't even more suitable for life with humans than they are. For example, it seems like many farm animals could've been bred to produce more females than males.

What are the limitations of selective breeding and evolution? Why are some traits modifiable and others not?
In 2018, we can't breed for sex, we can only cull the sex we don't want. It can be done in a dish now (when doing IFV), or by abortion. Back then they had to wait for an animal to be born to kill or toss away the one they didn't want.

Some traits are modifiable and others not because science.