by E Orix on 27 Dec 2009, 20:08
People look at birds as just all related but this is far from it.
Birds are grouped the same as say animals
Cats; Lions, Leopards and Tigers
Munias,Tri Coloured Nuns,Yellow Rumps, Silver Nuns etc.
Bovine; Cows ,Buffalo etc
Waxbills,St Helena , Cordon Blue etc
Cats won't breed with Bovines( Cows and Cats won't breed together)
but Lion and Tiger can and have
Same applies to the birds Munias won't cross with waxbills,but will inter breed readily.
Chickens will not breed with Ducks or Geese
They all have feathers as animals have hair.
You do get hybrids but some are both fertile (Bengalese),some are both infertile(Horse and Donkey) and some are half fertile either male is and female not or reverse. and example is Red Siskin/ Canary produce what is called an F1 Males are fertile females are sterile and these crosses were the basis of the Red factor Canary of today.
I hope this explains it as I am not a scholar.