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  • in reply to: "Carolina dogs" in reference panel? #7274
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    Jennifer
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    How do researchers handle this when sampling village/pariah dogs? For example, if you’re collecting DNA from, say, Indian Pariah Dogs, how do you “ensure” you’re only sampling “pure” ones, and not mixes of IPD with recently arrived strays of foreign ancestry, or even just plain ol’ mutts?

    I gather from articles I’ve read that Brisbin at least sometimes approves dogs for the CD studbook based solely on looking at photos and completed questionnaires from owners who mailed in that information, and at some other times, based solely on meeting and observing a dog someone adopted from a shelter somewhere. Maybe not the most scientific way to do it, especially in a time when, as Stephanie mentioned, there’s an increasing amount of romanticized public interest in these dogs. (For awhile there, there was an eyebrow-raisingly improbable number of “Carolina Dogs” and “Carolina Dog mixes” being posted to Petfinder–basically, “Well, it’s tawny, prick-eared and shorthaired, so let’s call it a CD”–but I notice they’ve recently quietly dropped CDs from their breeds list altogether, which makes me wonder if someone of influence complained.) But what else is Brisbin supposed to do? He knows better than anyone else what the real thing can look like, they need genetic diversity to build a breed, and wild-caught CDs are hard to come by and could even themselves turn out to be mutts anyway.

    in reply to: "Carolina dogs" in reference panel? #7271
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    Jennifer
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    It may be that there already are some Darwin’s Ark participants with registered CDs, I don’t know–this is, after all, a citizen science project designed to draw upon dog owners’ personal knowledge of their own dogs’ everyday behaviors. Currently, the UKC is the only registry for Carolina Dogs, and Brisbin himself is the keeper of the UKC Carolina Dog studbook, so to own a registered CD is by definition to own a dog Brisbin approved for addition to the studbook (or whose immediate ancestors had all already been thus approved and registered). I mention registration because I gather from previous statements by members of the Darwin’s Ark team that proof of registration is a prerequisite for their using a participant’s dog’s DNA as a breed reference sample. Which would make sense, since that’s how it’s usually done by any researchers or testing companies whose work requires verifying the purebred status of dogs who are specifically being studied as examples of that breed, or whose DNA will be used as a reference in breed mix analysis of other dogs.

    in reply to: "Carolina dogs" in reference panel? #7219
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    Jennifer
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    Have you seen the studies from Shannon et al (2015) and Ni Leathlobhair et al (2018)? Those are the two most recent genetic studies to include Carolina Dogs, and both concluded that all CDs tested were of predominantly European ancestry, with a range of 0-35% pre-Columbian/Asian ancestry at the level of individuals. Which is still a high average of pre-Columbian/Asian ancestry for an American dog type from outside the Arctic/Alaska region, but nonetheless paints a pretty different picture from what Brisbin had originally speculated, back in the days before this kind of testing was possible. AFAIK, the only other studies relevant to the CD are a couple earlier, more tentative ones that had looked only at mitochondrial DNA.

    Shannon et al: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4640804/
    Ni Leathlobhair et al: https://www.researchgate.net/publication/326211519_The_evolutionary_history_of_dogs_in_the_Americas

    I know Embark tests for Carolina Dog, FTR. They are fairly generic-looking dogs even when pure, in the sense that any number of mixes with a good dose of spitz and/or herding type in them could wind up looking quite a lot like one.

    in reply to: looks #7184
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    Jennifer
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    I guess(?) in principle you could, if your image hosting service wouldn’t consider that hotlinking and you’re using the correct HTML tags and attributes. A simpler way would be to just cut and paste the “Direct Link” for your picture(s) or album, which on most image hosting services will be in the form “https://NameOfImageHostingService/IndividualPhotoOrAlbumCode” or something like that. That would just appear as ordinary text on this forum, but any reader could then cut and paste it into their browser’s address bar to view the picture(s).

    in reply to: looks #7177
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    Jennifer
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    Which test? What was the exact breakdown of the results? And do you have a link to any photos of the dog? It’s hard to know what to picture when someone says a dog “looks just like a pit bull.”

    in reply to: results seem to be spot on #7168
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    Jennifer
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    Boxer mixes are often very fast, if they inherit the breed’s sprinter’s legs and fast-twitch : slow-twitch muscle ratio without its impeding top-heaviness. Like Corsos and Danes, Boxers descend from coursing mastiffs used to hunt wild boar, which required both lots of speed and lots of brute strength (boars fight back), so their build had to strike a balance between two opposing needs. A mix, though, could potentially wind up inheriting the speed traits but not so much the strength ones. Of course, her speed could also come from something else in her ancestry–it’s just a thought.

    in reply to: Research update #7150
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    Jennifer
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    So does this mean that Labs appear to show less behavioral diversity between individuals than other breeds? Or that Lab owners were more likely to choose the statistically least common answer to a question? Or something else?

    in reply to: Research update #7097
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    Jennifer
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    That workshop sounds really fascinating. My late mother had a very rare lysosomal metabolic disorder, and while she didn’t expect every medical professional she might encounter to be highly knowledgeable about her condition, still it was obviously important background info, so she had to develop multiple ways of introducing the subject, so that she could basically cycle through different terminologies until she hit on one that triggered recognition with whoever she was talking to. Perhaps today’s digitized medical records have alleviated that problem considerably(?) so that now the problem is more relaying the proper terminology to the patients, but in those days, for some diseases at least, the confusion flowed both ways.

    in reply to: Research update #7078
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    Jennifer
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    Well, you never know…might score some extra crumbs that way…(good at finding food)

    We sometimes offer both our dog and cat food containers, plates, or flatware to let them lick the residue off before we wash them. It always amazes me how exhaustive and meticulous a job both of them do of it, licking until long after every last bead of moisture and every pinprick-sized speck of food is gone. Yes, I’ve been known to lick such items on occasion too, but never that thoroughly–my taste buds stop being happy once the licks start tasting more of plastic, stainless steel, or tempered glass than of food. I know I have many more taste buds than they do though, so I guess my experience of it is just different.

    in reply to: science question — atavism, reversion and pariah morphs #7058
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    Jennifer
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    Thanks, Kathryn, for the informative answer. I’ll have to add that Coppinger book to my reading list. I’d never thought about it quite that way before…that if you’re conceptually lumping all non-purebred dogs in the world into one arbitrary “mongrels” category, you’ll probably tend to come up with some pretty far-fetched theories trying to account for the tendency of longstanding “pariah” populations to look a certain way. I think it was that Dunbar quote that really threw me for a loop, because I thought, OK, well here’s someone with serious credentials, and even he seems to be saying there really is some sort of “reversion” effect intrinsic to mixing different breeds that’s destined to generate a “primitive”-looking population in pretty short order. To be fair, the quote is 30 years old, and in context he was discussing the unreliability of breed ID in bite statistics, not trying to explain why “village dogs” look the way they do. Still, I find it hard to read it as anything other than implicit support for the “mutts morphing into pariahs” scenario, and indeed that’s why the person I saw post it chose to cite it. Of course, it’s completely true that housepet-descended “First World” shelter mutts, like many of us own, often have no overall resemblance to any breed in them, and also that the loss of “type” relative to their purebred ancestors tends to be especially pronounced when those ancestors were phenotypically extreme (which seems to be a theme with Dunbar’s chosen example breeds). But at least to the best of my limited understanding, that’s not because these mutts are “reverting” towards any particular predestined form or forms, and certainly not because natural selection was substantially in play for their near ancestors.

    in reply to: Results!! Question about "Unknown" #7044
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    Jennifer
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    The data are phased; Kathleen mentioned that in her overview of how to read and understand the results. link

    I don’t know what the average generational reach would be, but the breed results aren’t reported as a family tree organized into parental lines and generations, rather as a simple bar chart ordering the detected breeds from lowest to highest percentage of ancestry. example

    in reply to: Recent research #7043
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    Jennifer
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    Oh boy, that sounds really tedious having to manually convert all those ages. What do you mean about answers changing based on the dog’s age? Like the way some behavioral traits tend not to manifest clearly until sexual maturity, or that owners tend to perceive dogs’ strengths and weaknesses differently depending on how old the dog is, or…?

    in reply to: Got Zoe's Results Last Night #6949
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    Jennifer
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    I wonder with “American Village Dogs” to what extent it will ever be possible to confidently say whether trace matches with existing breeds truly might represent a purebred ancestor of that breed at some point further back in the line, or whether they might represent a shared ancestor with that breed much, much further back. Embark’s description of the “American Village Dog” does mention that “these dogs are almost completely descended from European dogs imported during the Colonial Era.” It looks like Darwin’s Ark also found trace amounts of several other breeds not detected by Embark in Zoe–some European, some Amerasian, some mixes of both.

    There was a study published last year examining genetic relationships between 161 breeds: Parker et al. 2017. One of the surprises from that study was that the GSD, in particular, showed significant genetic relationships with many distinctly American breeds, including breeds like the Xolo and Peruvian Hairless which hadn’t previously been supposed to have any such ancestry. The researchers weren’t sure whether this finding reflected unrecorded outcrossings to actual registered purebred GSDs in more recent times, or colonial-era interbreeding between truly indigenous American dogs and imported Southern European cousins of the German landrace herding dogs which were later selectively developed into the GSD.

    in reply to: Results!! Question about "Unknown" #6931
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    Jennifer
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    Thanks Kate! I knew that WP and Embark generally don’t update breed analyses over time, but they’re both always changing the array of markers they look at, so it makes sense that you’d have to purchase a new test kit if you wanted a more up-to-date analysis for your dog.

    in reply to: Results!! Question about "Unknown" #6924
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    Jennifer
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    Will individual dogs’ results be retroactively updated as the size and robustness of the reference panel improves, or will those improvements only affect dogs analyzed after the improvements are made?

Viewing 15 posts - 16 through 30 (of 39 total)