Domestic Dog – Canis lupus familiaris. ?!. Relatively wolf like. More like a rodent?. Homeless man with his dog. Paris Hilton. Questions :. 1. WHY are dogs and humans together? 2. WHO is the ancestor of the dog? (Is there more than one?)
Relatively wolf like
More like a rodent?
1.WHY are dogs and humans together?
2. WHO is the ancestor of the dog? (Is there more than one?)
3. WHEN did dogs and humans start living together?
4. WHERE did it happen first?
5. HOW did it happen? (Led by dogs or people?)
6. How can the breeds look so different and be so genetically similar (they can interbreed)?
What's in it for people
What's in it for dogs
"I do not believe...that all our dogs have descended from any one wild species"
Was he right...?
(Remember all those varieties can interbreed)
Dog origins – Who, where?
Most recent genetic evidence says...
Probably the East Asian gray wolf(China, Mongolia, Siberia)
(not the North American one, as we used to think)
But several different strains of wolf intermixed at different times.
Archeology vs. Genetics
15,000 years ago?
135,000 years ago?!
(probably closer to the former)
10,000 BCE, Israel – Buried with puppy
Red – current gray wolf distribution
X – origin of dog ancestor (approx.)
So... single origin of dogs; they came with people into the new world
How did dogs and humans come together? - Something in it for both parties...
Theory 1: people caught wolf puppies and raised them among people
Theory 2: dogs approached closer and closer to human settlements (scavenging)
[cf. other domesticated animals]
“People are organized into continuous settlements — villages where they remain for a long period of time, whether there were sitting on the edge of a shell fishery or on the edge of a coral reef. When humans live in the same spot for a long period of time, they create waste, including both sewage and, more importantly for the dog, leftovers. There are things people can’t eat, seeds that fall on the ground, things that have gone bad,” Coppinger says, “The garbage, which might be found in dumps, or just scattered near houses, attracts scavengers: cockroaches, pigeons, rats, jackals — and wolves.”
Shar pei skin infections, bloodhound eye infections
Too big or too small -> structural problems (esp. hips)
Origins of dog diversity
Coppinger – Flight distance - “My argument is that what domesticated — or tame — means is to be able to eat in the presence of human beings. That is the thing that wild wolves can’t do.”
Once we had dogs living with us, we could do...
Hunting, herding, guarding,
companionship, etc. (“smarter than chimps”)
Breeding ground for bacteria
All dogs are mutts – but now there are rules for “purity”
All modern dogs are very very close genetically – all can interbreed.
So how do you get so much PHENOTYPIC variation with so little GENOTYPIC variation (Darwin’s problem)?
One major way: changes in timing of development - a general principle in evolution (grow a little slower here, a little faster there)
That way, subtle genetic differences can translate into big morphological differences.
e.g. Neoteny - adults behave / look like puppies