Ducks and Geese are in the same family of birds, Anatidae, and both have 40 pair of chromosomes, so it is possible for them to produce young.
Quote: Abstract:
A hybrid between a domestic duck (male) and a domestic goose (female) acquired by the Zoological Gardens, Copenhagen superficially resembled a duck, but by a closer examination it was showed that morphologically and ethologically it showed characters of both duck and goose. Although it is a male it has never shown any sexual activity. I therefore tried to activate it by hormone injections. Treatment with gonadotropic hormones and with sexual hormone were both ineffectual. Therefore I conclude that this bird does not have the nervous mechanisms underlying the sexual patterns, because it is known that castrated male birds and young male birds show sexual activity when treated with hormones.
Apparently goose/duck crosses are an extreme rarity, but genetically, it is not impossible.
Inter-species breeding is rather common place, i.e. horses and donkeys are bred to make mules. More exotic examples are lions and tigers makers Ligers and Tigons.
What biologists consider two different "species" does not always mean they can't interbreed due to a genetic limitation. Sometimes animals are classified as different species even though they are inter-fertile. In the wild they either choose not to interbreed or are physically prevented from breeding through geography, lifestyle, or size difference. There are many species of beetles that are gentically compatible, but physically their genetalia do not fit each other, so they cannot breed naturally and are considered different species. It's fascinating.
Quote: Abstract:
A hybrid between a domestic duck (male) and a domestic goose (female) acquired by the Zoological Gardens, Copenhagen superficially resembled a duck, but by a closer examination it was showed that morphologically and ethologically it showed characters of both duck and goose. Although it is a male it has never shown any sexual activity. I therefore tried to activate it by hormone injections. Treatment with gonadotropic hormones and with sexual hormone were both ineffectual. Therefore I conclude that this bird does not have the nervous mechanisms underlying the sexual patterns, because it is known that castrated male birds and young male birds show sexual activity when treated with hormones.
Apparently goose/duck crosses are an extreme rarity, but genetically, it is not impossible.
Inter-species breeding is rather common place, i.e. horses and donkeys are bred to make mules. More exotic examples are lions and tigers makers Ligers and Tigons.
What biologists consider two different "species" does not always mean they can't interbreed due to a genetic limitation. Sometimes animals are classified as different species even though they are inter-fertile. In the wild they either choose not to interbreed or are physically prevented from breeding through geography, lifestyle, or size difference. There are many species of beetles that are gentically compatible, but physically their genetalia do not fit each other, so they cannot breed naturally and are considered different species. It's fascinating.