Saturday Morning Open Thread: Cooperation Is Evolutionary

Carl Zimmer, in the NYTimes, on dogs’ evolution “From Fearsome Predator to Man’s Best Friend”:

Dog brains… have become exquisitely tuned to our own. Scientists are now zeroing in on some of the genes that were crucial to the rewiring of dog brains…

As they reported [last week] in the journal Nature Communications, they found that the split started 32,000 years ago. Those early dogs would have encountered small bands of hunter-gatherers. People didn’t settle in villages to farm in East Asia until about 10,000 years ago.

After dogs split from wolves, their genes began to evolve in a new direction. Dr. Zhang and his colleagues were able to identify some of these evolving genes. A number of them, it turned out, are active in dog brains. (Dr. Zhang and some of his colleagues published some of these results last week in the journal Molecular Biology and Evolution.) …

The results offer some tantalizing hints about how wolves first turned doglike. “The conventional view is that the hunter-gatherers go out and get a puppy,” said Chung-I Wu of the University of Chicago, an author of the Nature Communications study. If humans actually did breed early dogs this way, then dogs would have descended from a very small population.

That’s not what Dr. Wu and his colleagues have found, though. Instead, it appears that a large population of wolves started lingering around humans — perhaps scavenging the carcasses that hunters left behind.

In this situation, aggressive wolves would have fared badly, because humans would kill them off. Mellower wolves, by contrast, would thrive. If this notion turns out to be true, it means that we didn’t domesticate wolves — they domesticated themselves. SLC6A4 may have played a crucial part in this change, because serotonin influences aggression.

To test these ideas, Dr. Zhang and his colleagues are gathering DNA from more dogs and wolves. They also hope to collaborate with cognitive scientists to see how variants of genes like SLC6A4 affect the behavior of dogs today. Their results may also help explain human evolution, because Dr. Zhang and his colleagues found that some of the same genes that evolved in dog brains, such as SLC6A4, also experienced natural selection in human brains.

“Humans have had to tame themselves,” said Adam Boyko of Cornell University, one of Dr. Zhang’s collaborators on the Molecular Biology and Evolution study. “The process is probably similar to dogs — you have to tolerate the presence of others.”

Progressively cooperative or not, what’s on the agenda for the start of the weekend?

64 replies
  1. 1
    Baud says:

    Hey, my dogs are still fierce predators . . . who want their tummies rubbed occasionally.

  2. 2
    Fred says:

    Dogs are like immature wolves. When wolves mature it seems they lose their playfulness. That is why they don’t make good house pets. When they are pups they are fun but adult wolves are not entertaining as well as being dangerous preditors.

  3. 3
    Heywood J. says:

    Memorial weekend bleg for you good folks: I have two guitar books published at Amazon now, and I’m running a free promo all weekend for both, and would appreciate it immensely if you could take a couple minutes and download to help with rankings.

    As an incentive, there are cat photos.

  4. 4
    raven says:

    Katy Lied

    Katy tried
    I was halfway crucified
    I was on the other side
    Of no tomorrow
    You walked in
    And my life began again
    Just when I’d spent the last piaster
    I could borrow
    All night long
    We would sing that stupid song
    And every word we sang
    I knew was true

    Are you with me Doctor Wu
    Are you really just a shadow
    Of the man that I once knew
    Are you crazy are you high
    Or just an ordinary guy
    Have you done all you can do
    Are you with me Doctor

  5. 5
    raven says:

    @Heywood J.: Done, someone is bitching that it’s not kindle friendly.

  6. 6
    raven says:

    @Fred: Did you see “Dogs Decoded”> This woman tried raising wolf pups at home until, one day, one jumped up on the kitchen table and got really aggressive! Back to the kennel. The show is really cool, it shows how dogs track your right eye to read emotion in humans. It also has a segment on this long project in Russia where they have tried to breed the aggressiveness out of fixes, It seems that the light in color the more passive. Really cool program.

  7. 7
    raven says:

    Lyudmila Trut


    Lyudmila N. Trut is head of the research group at the Institute of Cytology and Genetics of the Siberian Department of the Russian Academy of Sciences, in Novosibirsk. She received her doctoral degree in 1980. Her current research interests are the patterns of evolutionary transformations at the early steps of animal domestication. Her research group is developing the problem of domestication as an evolutionary event with the use of experimental models, including the silver fox, the American mink, the river otter and the wild gray rat

  8. 8
    c u n d gulag says:

    “The process is probably similar to dogs — you have to tolerate the presence of others.”

    Well then, I guess our Reich-wingers are half-way there – at least they tolerate the presence of people like themselves.

    I’ve been saying this for some time:
    When our righties shout “Freedom!”, and “Liberty,” what they mean, is the freedom to deny liberty to anyone who doesn’t agree with them.

    The weather here in Upstate NY is really sh*tty – aka: cold, rainy, and windy – until Monday.

    So, maybe I’ll bake a ham, and then cook some potato’s, celery, carrots, and onion, in the fat – YUM!!!
    And I’ll dress the ham with cloves, of course,and later glaze it with a mustard/apricot jam/orange marmalade mix.

    Of course, if you don’t hear from me by Tuesday, I’ve probably had a massive coronary or stroke, or gagged on grease.
    Enjoy the long weekend, folks!

  9. 9
    raven says:

    @c u n d gulag: We have incredible weather here, it’s 49 and clear as a bell and only going to the upper 70’s.

  10. 10
    WereBear says:

    @raven: This woman tried raising wolf pups at home until, one day, one jumped up on the kitchen table and got really aggressive! Back to the kennel.

    If you have ever been near adult wolves (I’ve seen them at some distance, briefly) you will understand the PERSONA they project which is nothing like domestic dogs.

    Her mistake was raising them as a pack? You can semi-tame a wolf by being their Pack.

    I believe the Russian Fox Experiment achieved domestication in three generations, with tools no more sophisticated than: this one is very cuddly and sweet.

  11. 11
    raven says:

    @WereBear: They bred the foxes to a lighter color if I recall.

  12. 12
    Linda Featheringill says:

    Morning, all.

    Gotta work today but I’m free for a couple of days after that.

    Corn is finally up in the garden. I am so impatient! It’s so hard to wait for the little rascals to proceed at their own pace!

    I spent a good chunk of yesterday transcribing reports about children who were born with things wrong with their brains. I think most of the problems were developmental, as opposed to injury at birth. At any rate, it was all very sad and depressing. Really got me down.

    Maybe today will be better. Maybe I’ll get to type about old folks with pain in their sacroiliac and such.

  13. 13
    TomG says:

    I was going to bring up the silver fox domestication experiment myself, because it is one of the coolest demonstrations of evolution I have read about.
    Wikipedia article

    The key takeaway is that the scientists were not at all aiming for physical changes. All they did was divide the foxes according to shyness or approachability. Yet over the years, the foxes who were bred for “greater approachability” (my term) also happened to have marked changes in appearance, more puppylike and less resembling their wild cousins.

  14. 14
    Ramalama says:

    My dog had wolf in him, I mean — recent wolf in him as opposed to building blocks wolf from way back.

    We had a retired lady come take care of our dog in our house when we had to take a trip. was where we found her and another dog sitter and they’ve both since become friends of ours. Anyway, retired lady declared our dog to have wolf in him based on the expressive eyes in addition to…looking like a wolf (he had mostly Malamute traits, though). She lived in the deep woods (Canada) at one point in her life and had a female wolf who couldn’t keep up with her pack settle in on her property. When the wolf realized it was ok for her to be there, she set up shop at the base of the long driveway, and howled anytime someone drove up. Wolf became very protective of the lady and her family for about a year, and then disappeared.

    She said the way our dog looked at us reminded her so much of her alarm wolf. People in the dog parks in Montreal told me how it was all the rage way back when … 30s 40s to mate sled dogs with wolves.

    My dog was good around most kids but my niece, who wants to be a dog when she grows up, made him take special notice of her. He had a special glint in his eyes whenever he saw her and so while we were very mindful of whenever he was around kids, we hovered when she and he were in the same room together. Niece only met him a handful of times since we’re in Quebec and my family is ‘Merican. And they didn’t really play together because he was huge and she so little. And he just wanted to treat her like his dog friends, biting her ears and pushing her around.

    But when he died she took it harder than the other kids.

  15. 15
    Amir Khalid says:

    In other news, Charles Ramsey continues to show real class.

  16. 16
    c u n d gulag says:

    Please don’t rub it in… :-(

    On the plus side – NO YARDWORK!!! :-)

  17. 17
    Ultraviolet Thunder says:

    32KYA is way farther back than most theories of canine/human interaction. I’d like to know what they base that on since it’s pretty critical to their theory.

  18. 18
    c u n d gulag says:

    @Amir Khalid:
    He turned down a year’s worth of free Mickey D’s food!

    I guess the man doesn’t have a suicide wish.

  19. 19

    My dog Sam (1989-2002) was a mutt with a great deal of Cairn Terrier in the mix: imagine Toto with floppy ears. His picture is on the banner of my blog. He was a wee doggie — he topped out at 17 lbs — but he was fearless. He would bark and growl at another dog no matter the size. And he was as loving a friend as you could want. He was also very protective of the pack. When I would sit at the computer, he would lie on the carpet facing out to the room keeping watch. I miss him every day.

    As for the weekend, this is Day 2 of the Long Weekend, and all the chores — car washing, oil changing, grocery getting, and laundry — were all done by noon yesterday. I’m only awake and doing because of noisy mockingbirds in the trees outside. They won’t shut up, and it’s a sin to kill them (or so I’ve been told), so here I am. Another steamy sultry day in South Florida.

  20. 20
    sm*t cl*de says:

    “The process is probably similar to dogs — you have to tolerate the presence of others.”

    Fortunately the intertubes have freed us of that constraint.

  21. 21
    Chris says:


    Technical question – are wolves and dogs the same species? (In the scientific, can-they-breed-together-and-have-offspring-that’s-still-fertile sense, personality and appearance aside).

  22. 22
    Ultraviolet Thunder says:

    BTW, thanx for the recommendations for Feedly as a replacement for Google Reader. I’m using both the desktop and mobile versions (app) and I like it quite a bit better than Reader.

  23. 23
    Ramalama says:

    @Mustang Bobby: Your guy looked like a cutie. I have a special affection for little dogs who have no fear. My dog loved them the best, though it was really comical watching both him and whichever little dog he befriended realize that there was no way they could play together.

  24. 24
    dmsilev says:

    @Ultraviolet Thunder: Here’s what the actual paper has to say; I’m not qualified to comment on how plausible the claims are:

    With an assumed mutation rate of 2.2 × 10−9 per year17 and a generation time of 3 years, the effective population size of dogs at the beginning of the bottleneck is found to be around 8,500 and the effective size of the extant Chinese indigenous dog population to be around 17,000. Compared with other domesticated species, which typically experienced a population shrinkage of several magnitudes18, 19, this level of population size reduction is rather weak.

    The population divergence time is estimated to be around 32,000 years ago, which is much older than previous estimates using mtDNA data9, 10 (see discussion).
    The divergence time between the dog and wolf that we estimated implies a more ancient age for domestication than suggested by previous studies9, 10. Even though the genetic evidence and fossil records in many parts of the world are still very preliminary37, archaeological remains of wolf-like canids, with some resemblance to the dog, as old as 30,000 years ago have recently been reported, although their status as dog is debated38, 39, 40, 41. A deeper divergence and a mild population size reduction during domestication suggest an evolutionary trajectory for dogs that is often called self-domestication42. Early wolves might have been domesticated as scavengers that were attracted to live and hunt commensally with humans. With successive adaptive changes, these scavengers became progressively more prone to human custody. In light of this view, the domestication process might have been a continuous dynamic process, where dogs with extensive human contact were derived from these scavengers much latter when humans began to adopt an agricultural life style.

    Edit: And from their Methods section, which I’m _really_ not qualified to comment on,

    Population demographic history
    We inferred the population demographic history using methods implemented in the package ∂a∂i (version 1.60), which is based on the joint site frequency spectra between multiple populations16. Site frequency spectra is first extracted from our genotyping data and then polarized using a red wolf (an outgroup species) that we sequenced in a separate study. To avoid biases in the coding regions, only SNPs in the noncoding parts of the genome more than 5 kb from any coding region were extracted. Non-parametric bootstrapping was done by resampling (with replacement) the same number of SNPs from the total pool of SNPs.

    We assumed that the mutation rate per year is 2.2 × 10−9 per year (ref. 17) and that the generation time is 3 years, thus the mutation rate per generation is 6.6 × 10−9 per generation. Using the genetic diversity θ (4 Neμ) estimated across the genome and the mutation rate per generation, we can get a hold of the effective population size for the extant wolf population. Using the relative sizes of different populations (Fig. 3) inferred from the demographic inference, we can calculate the population sizes of the other populations. The divergence time is calculated by combining the information from ∂a∂i and the population size estimates. In particular, the divergence time (τ) from ∂a∂i is measured in 2Ne generations. The divergence time in years will be calculated as 2Neτ × 3.

    In the demographic analysis, we were setting the possible range of time of domestication to be between 0 and 0.3 (equivalence of 100,000 years, that is, before modern human’s migration out of Africa). In the bootstrap analysis, time spans of much larger range were also explored. In replicates where the estimated divergence time was far beyond the possible domestication time (that is, 250,000 years ago or further), those estimates were removed from the final results. This is equivalent to putting a hard bound on possible range of parameter estimates.

  25. 25
    Soonergrunt says:

    My dog thinks she’s a predator. And she’s hell on crickets, let me tell you. But a frog just completely defeats her. We had wild rabbits in our back yard in the old house. They tunneled in under the fence. She would bark like crazy at them, and tear-ass down after them if we opened the door, but once she got within one body length or so, she’d stop in place and bark. The rabbits, of course, would bolt for cover and never be harmed.

  26. 26
    Ultraviolet Thunder says:


    That’s a reasonable sounding explanation. They seem to be hedging somewhat because of thin evidence.
    The situation might be complicated by the process happening simultaneously or repeatedly with different populations.
    Earlier estimates that I had seen were around 8-10KYA, coincident with the rapid development of agriculture and permanent fixed habitations.

  27. 27
    lectric lady says:

    This is not a new idea, but genetic evidence for an old one. See Budiansky, Stephen, The Covenant of the Wild (1992). Yale University Press (reprint ed, 1999).

  28. 28
    lojasmo says:


    Canis Lupus Familliaris (dogs) are a subspecies of the grey wolf. They can interbreed. Any dog with wolf hybridization within five generations is considered to be a wolfdog.

    Pretty sure mine is.

  29. 29
    maya says:

    It is my theory that my 5 year old pit bull rescue evolved from a pack of mules. Is there any grant money available whereas I can study this farther?

  30. 30
    Svensker says:

    @Heywood J.:

    I have two guitar books published at Amazon now, and I’m running a free promo all weekend for both, and would appreciate it immensely if you could take a couple minutes and download to help with rankings.

    Went to your link but couldn’t click on anything. Are we supposed to go to Amazon? Some pointers for the olds (or at least this old) please.

  31. 31
    Brother Machine Gun of Desirable Mindfulness (fka AWS) says:

    Weird that I had a dream last night about getting a dog, like a dog would fit in with the two female cats here in this apartment. yeesh. but the puppy was so cute.

  32. 32
    Brother Machine Gun of Desirable Mindfulness (fka AWS) says:

    @Heywood J.: I see the titles, but I can’t click on them.

  33. 33
    quannlace says:

    I just looked at my dog and said, ‘Is your brain exquisitely tuned?”

  34. 34
    wonkie says:

    @Heywood J.: Okay. Did it! Now will you return the favor? Go to the Kindle Store and put Jill Kearney in the search. That’s my book The Dog Thief and Other Stories. People into dog rescue might like the title novella. The other stories aren’t about animals, though.

  35. 35
    Brother Machine Gun of Desirable Mindfulness (fka AWS) says:

    @wonkie: How did you get the links to work. I’m actually interested in the subject matter of Heywood J’s books, but I can’t click on the titles.

  36. 36
    wonkie says:

    The idea that dogs domesticated themselves coincides with primary resource history of the relationship between dogs and Native Americans in the west. Lewis and Clark among others noted that western NA commmunities included packs of dogs that lived in the community but usually were not treated as pets. The dogs ate by stealing food or by scavenging scraps., The puppies, in turn, were eaten by the people.

    The dogs acted as lookouts by barking and got some protection from preditors by living in proximity to people.

    One of the British explorers on the BC coast wrote that coastal hunting camps usually had abandonned starving dogs which had been brought to the camps ot serve as lookouts and as food, but were left behind when the hunters went home.

    So a somewhat symbiotic rfelationship wherein both people and dogs got food and some protection. There were individual dogs that were valued by individual people and had a special pet status. It just wasn’t the norm.

    Francis Parkman observed the same pattern.

  37. 37
    Ultraviolet Thunder says:


    “Technical question – are wolves and dogs the same species? (In the scientific, can-they-breed-together-and-have-offspring-that’s-still-fertile sense, personality and appearance aside).”

    There’s really no easy answer to that. Here’s a decent discussion of the issue:

  38. 38
    cmorenc says:

    My Italian Greyhound has evolved quite a ways from her ancient wolf ancestry. I don’t think any self-respecting wolf would climb on a couch and then beg to be covered with a light blanket while snuggling in your lap.

  39. 39
    Slugger says:

    I wonder to what extent dogs modified humans. When I walk my husky some people avoid us, some tolerate us, and some seem to instantly like the dog. A man/dog combo is a much better hunting team than either alone. Walking through waist high grass, I can see rabbits but can’t catch them. The dog can learn commands like directions and get the rabbits that would otherwise be hidden from them. Dogs had to evolve to be “tame,” but did we evolve to like canines rather than fear them and be emotionally available and readable by the dogs?

  40. 40
    Hungry Joe says:

    Talk about “attuned”: My Aussie mix knows when we’re going for a walk, even when I try not to give any hint at all. I’ll go into the kitchen (where the leash is) to get a drink of water, and she barely glances at me. I’ll go into the kitchen to get the leash for a surprise walk, telling myself (so as not to tip my hand) “I’m going to get a drink of water” — and she leaps up and is instantly at my heels. Damned if I can figure out how I give it away.

  41. 41
    Ultraviolet Thunder says:

    @Hungry Joe:

    Probably the way you walk. Your stride is different when you’re going in the other room compared to starting a long walk.
    Aussies have to have a finely tuned sense of what a sheep is going to do next, and that’s based on body movement.

  42. 42
    RaflW says:

    “The process is probably similar to dogs — you have to tolerate the presence of others.”

    I suppose even in gated Republican enclaves, this is somewhat true.

  43. 43
    Hungry Joe says:

    @Ultraviolet Thunder: I agree. That’s why I tell myself to use my Going to Get a Drink of Water stride. But apparently I can’t do it perfectly; there’s some difference in my gait that I’m unaware of but that she picks up on. If she ever learns to play poker she’ll clean me out.

  44. 44
    YellowJournalism says:

    @Mustang Bobby: Cairn Terriers are really the sweetest little toughies. Ours is a mix of Cairn and pug, which gives her a puppy’s playfulness even at almost seven years old. Right now she’s feasting on Cheerios my youngest “donated” to her food bowl.

    And on the walking thing, I just have to think about a walk, and I swear she trots to the door and starts wiggling her butt with excitement.

  45. 45
    Ultraviolet Thunder says:

    Our Geezer, a Poodle/Maltese mix knows walkies time by the time of day. If you stand up in the late afternoon he knows it’s on. Then we make him go get his harness from the walkies bag. No walk until he brings the harness. Much barking!

  46. 46
    Lazslo Anton Zapotec says:

    @Fred: I suspect the same observation can be applied to humans as well.

  47. 47
    Johnny Coelacanth says:

    Hey, Heywood/Dan, your links don’t work on your page. At least not for me on Chrome build 26.0.1.

  48. 48
    vogon pundit says:

    Loved the Times article. Our dog has *nearly* domesticated me, but i’m not ready to off leash yet.

  49. 49

    Zimmer is a great science article. He’s got a big piece in THE ATLANTIC about a disease where you grow a second skeleton.

  50. 50
    eddieb says:

    I find it interesting that the article says that “Man” was involved in the selection of the wolves/dogs

    In this situation, aggressive wolves would have fared badly, because humans would kill them off..

    Then goes right ahead and tells us they are self selecting. The reality is there is a special bond that appears between Man and Dog that is universal in wolves and through Domestication the wolf is changed just as it has been changed in all domesticated animals except for that special bond.

  51. 51
    Steeplejack (tablet) says:


    At the upper right on his page are links to Amazon to “purchase” his books. When you click those you go to Amazon pages where the price is $0.00 to download Kindle editions.

    Read other comments. Maybe it’s a browser issue.

  52. 52
    Karmus says:

    FWIW the book links worked okay in my updated Firefox on XP. Thanks for the books! Also for a very cool discussion. I get off on the whole “what’s a species” thing? Had read about the fox domestication thing before (incl. Wikipedia article). Seem to recall there, or somewhere, that one of the physical characteristics displayed by foxes selected & bred for tameness included floppy ears.

  53. 53
    swbarnes2 says:


    Right, floppy ears is in fact a trait found in lots of domesticated species. The genes that changed to make the animals tame apparently wear many hats, which is why you see a lot of physical changes in tamed populations. The tamed foxes were more likely to have color variations, and tame animals in general are much more likely to generate “sports” than wild populations. And I don’t think that’s an issue of the sports dying earlier in wild populations; I think the genetics of the tame animals makes sports more likely to pop up in tame populations than in wild populations.

  54. 54
    Steeplejack says:

    @Steeplejack (tablet):

    Just got on here with my computer. Adblock Plus blocks the Amazon links because they are ads.

    Links for Heywood J.’s books:

    Practice Power: Secrets to Practicing and Playing Amazing Guitar.

    Climbing the K2: Kreutzer Etude No. 2.

  55. 55
    Heywood J. says:

    @raven: Thanks Raven! Yes, one of the books has guitar tablature in JPG format, and the initial upload was formatted incorrectly. I have (hopefully) since fixed that issue; but if you see a black camera with a red triangle and exclamation point anywhere in there, please let me know.

  56. 56
    Heywood J. says:

    @Svensker: The Amazon links for the books should be at the top in the right sidebar on my blog page. Seems to be working in both IE9 and Firefox for me, so I don’t think it’s a browser issue.

  57. 57
    Heywood J. says:

    @Steeplejack: Awesome, thanks for catching that! And big thanks to everyone who’s checking out the books. I am very excited about this whole self-publishing thing, and in fact am spending most of my holiday/birthday weekend working on more (and bigger) tab books; each of the next two books will probably be around 60 pages when done (and still reasonably priced; I am not trying to grind 15 bucks out of people for these things).

    If you have time, please feel free to leave a review on the Amazon page, good or bad. :P

  58. 58
    Jebediah says:

    @Heywood J.:

    Done –

  59. 59
    confusedponderer says:

    For the same reason ravens lead wolves to moose today, wolves led humans to mastodons back then. I know. I was there. Thog The Mastodon Slayer, I was. Now? Just call me Chuck….

  60. 60
    Heywood J. says:

    @Jebediah: Thanks, I hope you enjoy the book(s)!

  61. 61
    pluky says:

    @Chris: Dogs and wolves are completely inter-fertile.
    Generally, drift sufficient to speciate takes more than broadening of the degree of allelic variation between subtypes. At the very least one needs substantial transposition (changes in gene location either on a chromosome, or between chromosomes), or at an extreme changes in ploidy (i.e. chromosome number).

  62. 62
    Brother Machine Gun of Desirable Mindfulness (fka AWS) says:

    @Steeplejack: Glad I checked back on this thread. Just downloaded the two books. look forward to checking them out.

  63. 63
    Bloix says:

    It would have been nice if that article had credited Raymond and Lorna Coppinger, the evolutionary biologists, dog breeders, and dogsled racers who developed the theory of dog evolution as the self-domestication of wolves as scavengers over ten years ago. Over the past decade the Coppinger’s theory has become the leading theory among evolutionary biologists. Wu, Zhang and their colleagues didn’t develop these ideas, although they may be helping to confirm them.

    The Coppinger’s theory of dog evolution was the subject of an episode of Nature on PBS about five years ago:

    And anyone who cares about dogs at all should read the Coppinger’s 2001 book for lay audiences, called Dogs: A Startling New Understanding of Canine Origin, Behavior & Evolution. It will help you understand your dog in ways that you wouldn’t imagine.

  64. 64
    Heywood J. says:

    @Brother Machine Gun of Desirable Mindfulness (fka AWS): Thanks, hope you enjoy them. Love the handle, btw.

Comments are closed.