Thus the genetic basis to the origin of bird species is to be sought in the inheritance of adult traits that are subject to natural and sexual selection. ↗
With the absence of a flu vaccination last year, I did not take a flu shot; but there is still some immunity that carries over from year to year; but about every 30 years, there is a major change in the genetics of the flu virus. ↗
It's perfectly obvious that there is some genetic factor that distinguishes humans from other animals and that it is language-specific. The theory of that genetic component, whatever it turns out to be, is what is called universal grammar. ↗