This manslaughter-by-Husky thread had me wondering: Do dogs recognize relatives of other dogs, and if so, do they treat them differently? For example, would dear, fluffy Chomper recognize – by scent or otherwise – an estranged pup-in-law? Would the dog be any less inclined to attack a relative? Less inclined to mate with one? Would it care at all one way or another?
And what about dogs recognizing human kinship? Do dogs exhibit any sort of familiarity towards their owner’s siblings, parents, or offspring? Or towards identical human twins? Facial similarities aside, do human relatives share enough identifying genetic material to enable dogs to sense them as being related?
I am not sure on the answer but do have an anecdote.
We foster rescue dogs and many come from the same reservation. We had a dog and an interested family who had previously adopted from the organization. They came over to meet our dog and brought theirs to see if they were compatible. They were NOT! They really got in to it!
After talking, we found out that they came from the same reserve and were actually brothers. So I’d guess that they grew up fighting each other for food and still remembered. They hadn’t seen each other for about eight or ten months.
Well, there is the problem where brothers and sisters will mate, which you would think wouldn’t happen if they realized they were related, as the offspring would have a lower chance of survival.
Of course, my logic could be wrong. I just know the above is a common problem when breeding. In fact, any blood relatives of opposite sexes are usually kept away from each other: the reason I got my chihuahua was that he was trying to mate with his daughter.
More anecdotes: Our neighbor’s Shih Tzu was separated from his mother (the mother is owned by family friends) after weaning and then not reintroduced for about a year. Now, they are brought together every few months, and they do NOT get along. They tolerate and ignore each other at best, fight at worst.
Many animals have evolved defenses against this, though it doesn’t necessarily work by recognizing kin per se. For instance, males who are just coming of age might be forced out of the pack/herd/whatever and made to join or form other packs/herds/whatever. If no male lives in the same group that he grew up in, but every female does, then immediate-kin incest will be impossible, and near-kin incest (such as between cousins) will be uncommon.
We had a german shepherd when I was growing up; he was pretty vicious for some strange reason, barking and lunging at anyone who walked past our yard. (Strong chain!) Yet, when my 1yo nephew was over, he not only did not snarl at this little kid he’d never seen before, the kid went up to him and was pulling on his upper lip and he did nothing but take it calmly.
Not sure what makes dogs act the way they do. Their psychology is very different than ours; things like whether they think themselves leader or follower, what’s a member of the pack and what is food, etc.
Can’t remember where I read it, but it might have been in Jared Diamond’s The Third Chimpanzee that scientists have done experiments that are along this angle and have concluded that the separated related animals do not “recognize” one another.
The experiment is really hard to design and tried to determine whether the animals would be “nicer” to one another if they were related. In reality, if you are a species that competes for resources it doesn’t really help you are nice to your brother. Both of you will end up not being able to continue the genetic line if you then have to “share” resources designed to only support one of you.
Dogs are social animals, but must also compete with each other to maintain status. They don’t really care if the animal they are competing against is their brother or sister.
When it comes to mating, it doesn’t seem to matter to some animals, but others it does. IIRC, from the book, some social animals prefer to want to mate with someone who looks like those they were raised around. If you take a black-marked bird sub-species of bird and raise it with the red-marked sub-species exclusively, it will want to mate with the red-marked sub species it was raised around, not the black-marked one.
There is at least one alternate explanation I can come up with: territoriality. People passing by on the street were encroaching on the borders of “his” territory, and so your dog put up a display intended to show his strength and his claim of territory. This might make you assume that the nephew would be seen as even more of a threat, since he’s gone beyond the borders to the interior of the territory. On the contrary, by being inside the pack territory, your dog perceived that the child must be a pack member, and therefore accepted.
I’m not saying this is the only explanation, but it is another hypothesis that would have to be considered and tested before we accepted that the dog recognized a familial relationship between you and your nephew.