At least 20
genes under positive selection in cats are associated with vision - related pathways, which fits with the importance of visual acuity for these natural - born hunters.
There are at least six genes that look to be
under positive selection in cats that are associated with hearing capacity; we know this because mutations in these genes cause nonsyndromic recessive hearing loss or deafness.
Earlier, I mentioned how the generation of dog breeds has caused large stretches of DNA to be
placed under positive selection, generating breed specific «haplotypes.»
In natural selection, neighboring mutations «hitchhike» with the mutation that is
under positive selection, leading to a loss of genetic diversity near the favored mutation.