Skeptophilia (skep-to-fil-i-a) (n.) - the love of logical thought, skepticism, and thinking critically. Being an exploration of the applications of skeptical thinking to the world at large, with periodic excursions into linguistics, music, politics, cryptozoology, and why people keep seeing the face of Jesus on grilled cheese sandwiches.

Tuesday, September 25, 2018

Canine DNA analysis

When we adopted our latest rescue dog, Guinness, the people at the shelter told us that he was a Black Lab/Akita mix.  He certainly looks like it:

But I've heard from a lot of people that the assessments made at shelters are guesses at best, so a few months ago we had him DNA tested.  The results:

He is neither Black Lab nor Akita.

The test gave us the following results, most of which seem spot-on.  The largest portion of his ancestry is Staffordshire Terrier, which is one of the breeds from which Pit Bulls are bred.  He has the broad chest and blocky head of a pitty for sure.  The next three on the list were Husky, Chow, and Dalmatian.  He's got a curly tail and a thick, sleek coat, so those make some sense as well.  The only one I'm not buying is the last one on the list, which is Bichon Frisé, which (for the non-doggy people in the audience) is a small white dog that looks like a cross between a poodle and a cotton ball.

Maybe the white splotch on his chest and the tips of his toes are from his Bichon ancestry, I dunno.  Or maybe one just ran into him at some point, and that's the splat mark.

So okay, maybe the DNA tests have their issues, too.  But at least the majority of it makes sense, from his appearance and personality, the latter of which is seventy pounds of spring-loaded bounce.  He has two settings: full throttle and off.  Our mellow old coonhound, Lena, frequently looks at him with this expression that says, "Dude, you have got to switch to decaf."

This all comes up because of a study out of Arizona State University that appeared in PLoS-One a couple of weeks ago.  Titled, "More Than a Label: Shelter Dog Genotyping Reveals Inaccuracy of Breed Assignments," the researchers took DNA samples from nine hundred shelter dogs and ran a full genotypic analysis on them.  The results were startling; they found ancestry from 125 different breeds, and the accuracy of the breed assignment by the shelter was only ten percent.

It shouldn't be surprising; the handful of genes that codes for basic body shape and features like coat color, eye color, ear shape, and so on, and relatively responsive to selective breeding, and since that's what we're basing our assessment on, it stands to reason we'd get misled.  If you keep selecting the same thing over and over in two unrelated lineages, you'll eventually end up with their progeny looking like each other.  (This is called convergent evolution and is why the marsupial sugar glider and the flying squirrel are so strikingly similar; it's also why distantly-related groups of humans who live near the equator all have dark skin despite not sharing recent ancestry.)

"Breed identification has quite an outsize role in people's perceptions of dogs," said Clive Wynne, professor of psychology and head of the Canine Science Collaboratory at ASU, and co-author of the study.  "'What breed is he?' is often the first question people ask about a dog, but the answer is often terribly inaccurate."

As far as Guinness, I did ask what breed he was, but it was more out of curiosity than any kind of deciding factor regarding our potentially adopting him.  I fell for him right away, and he's turned out to be a sweetheart, despite being (and I say this with the utmost affection) a big galoot.  (Which my wife tells me in Latin translates to "galooteus maximus."  We are all about multilingual wordplay in this family.)

But it's still interesting how far wrong they were.  I get why they thought "Black Lab," with his shiny, thick, jet-black coat; it never really occurred to me to question it.  When I got the test results back, I was pretty stunned.

I guess it's no wonder, though, with a 90% fail rate.

So anyhow, keep adopting rescue animals -- it's the best way to go.  We've always gotten rescues and never gone wrong.  But don't necessarily believe what they tell you about the breed.

Now, I gotta go, because Guinness is ready to play his sixth round of "fetch the rubber ball over and over."  Simple pleasures, y'know.  And maybe I can get him to run off some of his ya-yas.  As the trainer told us, "A tired dog is a good dog."


This week's recommendation is a classic.

When I was a junior in college, I took a class called Seminar, which had a new focus/topic each semester.  That semester's course was a survey of the Book Gödel, Escher, Bach: An Eternal Golden Braid by Douglas Hofstadter.  Hofstadter does a masterful job of tying together three disparate realms -- number theory, the art of M. C. Escher, and the contrapuntal music of J. S. Bach.

It makes for a fascinating journey.  I'll warn you that the sections in the last third of the book that are about number theory and the work of mathematician Kurt Gödel get to be some rough going, and despite my pretty solid background in math, I found them a struggle to understand in places.  But the difficulties are well worth it.  Pick up a copy of what my classmates and I came to refer to lovingly as GEB, and fasten your seatbelt for a hell of a ride.

[If you purchase the book from Amazon using the image/link below, part of the proceeds goes to supporting Skeptophilia!]

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