Taimyr wolf and the origins of dog
There’s an ongoing debate about where and when dogs originated. The when part might be closer to an answer now. Genetic drift is used by evolutionary biologist to try to recreate the lineage of species. The discovery of a 35,000-year-old wolf rib bone in the Taimyr peninsula in northern Siberia was the key to this story. The DNA from that bone suggests that it diverged from a common ancestor of present-day wolves and dogs near the beginning of the domestic dog lineage. Their technique uses genetic drift of ‘regular’ DNA and mitochondrial DNA.
► Genetic Drift
There are non-lethal random mutations in DNA that survive to the next generation due to natural selection and sometimes due to ‘luck’. Surviving by natural selection makes sense, a mutation affords an advantage so that offspring should excel and survive. Genetic drift is when a mutation doesn’t necessarily result in an advantage but is nevertheless passed on ‘by chance’. Tracing these mutations help create a lineage for evolutionary biologists.
► Mitochondrial DNA vs. Nuclear DNA
Mitochondria are the energy power plants inside cells. They have a few genes necessary for oxidative phosphorylation, which is a fancy term for making energy. The nucleus of the cell is where the chromosomes are. Nuclear DNA is the DNA that you hear about in the news, for example in forensic science. In the figure below, you can see that mitochondrial DNA is passed on only by the mother while nuclear DNA is passed along by both parents. Genetic drift in mitochondrial DNA is much slower and helps refine the lineage of a species. It is slower because it is only inherited by half of the genetic source, i.e., the mother.
You can read a summary of the article in layman’s terms here:
Arctic find confirms ancient origin of dogs
http://news.sciencemag.org/biology/2015/05/arctic-find-confirms-ancient-origin-dogs
Full article and source of the very cool graphical abstract:
Ancient Wolf Genome Reveals an Early Divergence of Domestic Dog Ancestors and Admixture into High-Latitude Breeds
Skoglund et al
Current Biology May 2015
http://www.cell.com/current-biology/abstract/S0960-9822(15)00432-7
Source for the mitochondria DNA figures:
University of California Museum of Paleontology’s Understanding Evolution (http://evolution.berkeley.edu) http://goo.gl/WZgKRV
A bit more reading:
How the wolf became the dog (full article behind paywall)
http://news.sciencemag.org/environment/2015/04/how-wolf-became-dog
Late for #FidoFriday but always on time for #ScienceEveryday
May 23, 2015
Interesting article!
May 23, 2015
Thanks Kathryn Huxtable. I’m glad it didn’t offend my cat loving friends, since I posted this on #caturday.
May 23, 2015
Nice post Chad, I invite you to share this post over on Science on G+, we always like well written, well researched, well referenced posts and this one has all three.
Done like a Viking.
May 23, 2015
I will do that, like a Viking, Gary Ray R.
May 23, 2015
Someone was telling me that foxes were being domesticated as pets and that it takes only a few generations of breeding to bring out domestic traits in them.
May 23, 2015
#protip say ox phos to avoid saying oxidative phosphorylation 🙂
May 23, 2015
I figured that was too much jargon, Rajini Rao. I’ve been meaning to write about the domestication of the silver fox in Siberia for a long time. It’s a fascinating story that spans decades of work.
May 23, 2015
Would love to see that story too, Chad Haney . Don’t know much about it.
May 23, 2015
Rajini Rao http://blogs.scientificamerican.com/guest-blog/mans-new-best-friend-a-forgotten-russian-experiment-in-fox-domestication/
May 23, 2015
Rajini Rao, have you seen graphical abstracts before? I think it’s a great idea.
May 23, 2015
Yes, I like them too. We’re asked for them at the publication stage. Often we design a graphic just for this purpose- it’s creative and the pressure is off because the paper is already accepted!
May 23, 2015
I don’t see them in the journals I read.
May 23, 2015
You’re right, it’s a subset but they range from solid journals like Biochemistry to the elite ones like Cell.
May 23, 2015
Maybe the journals I read can evolve. 😉
May 23, 2015
As long as they don’t do this:
http://www.stemwomen.net/recognising-sexism/
May 23, 2015
I remember that, Rajini Rao. I’m glad my area of research hasn’t been tainted by a coconut bra or broteomics.
May 23, 2015
Haha, stay away from pina coladas just in case 😀
May 24, 2015
This is an interesting timesink I can go down. I kept trying to draw a line from Dire wolves – to modern wolves to dogs. So very interesting!
May 24, 2015
SciFi Author: Lacerant Plainer, I’m glad to have provided the rabbit hole.
May 24, 2015
This stuff is interesting Theory. Don’t pretend it’s a fact though.
May 24, 2015
Chad Haney I feel like Alice! 🙂
May 24, 2015
i see
May 24, 2015
Rajini Rao yhey cant be domesticated its just there learning to take advanteg of us
May 30, 2015
very intreresting…good
June 4, 2015
Thanks I will do that
June 4, 2015
thank you