2. DOMESTICATION
HOWDID WE DOMESTICATEANIMALS?
‣ There was no master plan
‣ At first our relationship to animals was the same as any other large
animals
‣ They were either food sources or threats, or neither
‣ We hunted some; scavenged others
‣ Our mode of life was in small “troops” (a term used for primate
groups) as part of larger regional “bands”
‣ We were primarily foragers rather than hunters
3. DOMESTICATION
THE CASE OF DOGS
‣ Dogs are thought to be varieties of wolves
(Canis lupus lupus)
‣ May have been domesticated in two
regions: central Asia and east Asia from the
Asian wolf (C. l.chanco)
‣Wolves (all canids,
really) crossbreed
widely Red wolf
Canis lupus (gray wolf) and one of
its subspecies, C lupus domesticus
4. DOMESTICATION
THE CASE OF DOGS
‣ Dogs are thought to be varieties of wolves
(Canis lupus lupus)
‣ May have been domesticated in two
regions: central Asia and east Asia from the
Asian wolf (C. l.chanco)
‣Wolves (all canids,
really) crossbreed
widely Red wolf
Canis lupus (gray wolf) and one of
its subspecies, C lupus domesticus
5. DOMESTICATION
DUALORIGIN
‣ Recent work has suggested
that domestic dogs are of
mixed ancestry, having been
domesticated once in
Europe/ Middle East and
once in Asia around 20,000ya
‣ Dingos are derived from
Asian singing dogs around
5000ya
‣ All dogs and wolves are
considered varieties of C.
lupus
Laurent A. F.Frantz et al. Science 2016;352:1228-1231
6. DOMESTICATION
HOWDID THIS HAPPEN?
‣ The reigning hypothesis is that
wolves would scavenge from
human campsites
‣ The more human-tolerant
individuals got more food
‣ Human-tolerance led to greater
interactions with humans, and thus
more food
‣ Thus there was inadvertent
selection for wolves that could
interact with humans
7. DOMESTICATION
BELYAEV’S
EXPERIMENT
▸ Soviet geneticist Dmitry Belyaev was barred
from research for political reasons
(Lysenkoism)
▸ Bred Russian silver foxes
▸ Would feed and breed the individuals that
would approach their feeders
▸ Within ten years, he had evolved foxes with
dog-like features
8. DOMESTICATION
BELYAEV’S EXPERIMENT
▸ Critics note that his breeding stock
came from a Canadian site that
already had bred for affability (Lord et
al. 2019)
Lord, Kathryn A., Greger Larson, Raymond P. Coppinger, and Elinor K. Karlsson. “The History of
Farm Foxes Undermines the Animal Domestication Syndrome.” Trends in Ecology & Evolution
online (December 3, 2019). https://doi.org/10.1016/j.tree.2019.10.011.
9. DOMESTICATION
BELYAEV’S EXPERIMENT
▸ Belyaev selectively bred from kits that
approached their feeders
▸ In ten generations, the kits’ ears
drooped, their tails began to wag
when they were happy, they started to
bark, and their coats started to show
patterns
▸ This showed that wild-type animals
under selection can change body
shape and behaviour very rapidly
Wild-type response to humans
Domesticated response
11. DOMESTICATION
ANIMALS THAT HAVE BEEN DOMESTICATED
Zeder,
Melinda
A.
“Domestication
and
Early
Agriculture
in
the
Mediterranean
Basin:
Origins,
Diffusion,
and
Impact.”
Proceedings
of
the
National
Academy
of
Sciences
105,
no.
33
(August
19,
2008):
11597.
https://doi.org/10/cqxmb7.
12. DOMESTICATION
ANIMALS THAT HAVE BEEN DOMESTICATED
Mountain Goat
Mou
fl
on Sheep
Wild Domesticated
Teach
Middle
East
@
Chicago
13. DOMESTICATION
Clockwise (from top left): kiang (E. kiang), Przewalski's horse (E. ferus
przewalskii), Grévy's zebra (E. grevyi), domestic horse (E. f. caballus), onager (E.
hemionus), plains zebra (E. quagga), donkey (E. africanus asinus) and mountain
zebra (E. zebra)
ANIMALS THAT HAVE BEEN DOMESTICATED
Clockwise (from top left): kiang (E. kiang), Przewalski's horse (E. ferus przewalskii),
Grévy's zebra (E. grevyi), domestic horse (E. f. caballus), onager (E. hemionus),
plains zebra (E. quagga), donkey (E. africanus asinus) and mountain zebra (E.
zebra)
Equus genus
Subgenus
Scienti
fi
c
name
Common name
Chromosome
number (2n)
Hippotigris
(Zebras)
Equus zebra Mountain zebra 32
Equus grevyi Grévy's zebra 46
Equus
quagga
Plains zebra 44
Asinus
(wild asses)
Equus
africanus
African wild ass;
includes
domesticated donk
ey
62
Equus
hemionus
Onager, hemione,
or Asiatic wild ass
56
Equus kiang Kiang 52
Equus
Equus ferus
caballus
Domesticated horse 64
Equus ferus
przewalskii
Przewalski's horse 66
Wikipedia
18. DOMESTICATION
THE ORIGINS OF AGRICULTURE
▸ How did it happen?
▸ Nomadic humans subsisted on wild wheat and other seed bearing
grasses
▸ To eat them, the seed needed to be husked and ground
▸ A certain amount of seed was spilled, and germinated the next year
▸ Since humans reaped the most seed bearing, more seed bearing
varieties grew in each place
▸ On returning to that locale, the process was repeated
▸ Over time humans began to plant and water these seeds
▸ Eventually this evolved into horticulture
19. DOMESTICATION
INADVERTENT SELECTION V. ARTIFICIAL SELECTION
▸ The process of domestication was coevolution:
▸ The animals and plants changed
▸ The humans changed (mostly culturally, but also
biologically – lactose tolerance; diabetes resistance)
▸ Farming had a toll – longer work and shorter statures
▸ Humans suffered individually, but population size increased
dramatically
▸ Led to large scale societies from ~250 to tens of thousands
20. DOMESTICATION
INADVERTENT SELECTION V. ARTIFICIAL SELECTION
▸ Coevolution is due to inadvertent effects on one species by
other species (humans are another species)
▸ But once we learned how to get the breeds we wanted, we
could do it deliberately, and so arti
fi
cial selection began
▸ It’s all about relative
fi
tness
▸ In wild environments, change happens at the pace of
ecological change
▸ In arti
fi
cial environments, it happens at the pace of changes
to cultural goals (economic, aesthetic)
21. DOMESTICATION
THE EFFECTS OF DOMESTICATION ON HUMANS
▸ We changed our way of life:
▸ From nomadic to sedentary
▸ From relatively stress-free long lives to lives of hard work
and shorter duration
▸ We changed what we could digest (milk, carbohydrates)
▸ We adapted to our domesticated organisms, behaviourally
and biologically
▸ The
fi
nal result of agriculture is urbanisation
