Friday, February 6, 2009

Wolves love dogs, Dogs love wolves

Here's an article (New World Wolves and Coyotes owe debt to Dogs) that relates to our understanding of the species concept. “This is an important paper that among other things should make us revisit and likely revise what we mean by a ‘pure’ species.”
Geez, how much biology can you learn! Speciation, genetics, mutations, adaptive advantage, interbreeding, hybridization. Wow!


Period 2 Jenn said...

I thought this was very interesting, considering that the pale colors in dogs is significantly more common than in wolves. If this cross-breeding between dogs and wolves is so prominent, and has existed for around 50,000 years, then why are there so many issues for species of wolves up in Alaska? Why don't the two species mate on their own if they're so closely related? I also thought it was interesting that this mutation of color provided immunity to viral skin infections, when it seems like something as trivial as skin color serves little to no purpose.

Period2marika said...

I agree with Jenn. This seemed very interesting to me. I had a hard time figuring out what the problem or benefit from the mutation was because the article did not make this clear until the end. I wish that the article had elaborated on what the benefits of the mutation are. In other words, they mentioned that it provides immunity to viral skin infections, but they didn't explain the genetics of this: I agree with Jenn that it is interesting that skin color can provide this immunity.
I also was very confused about the dating of the wolves' various species. I also wonder if there are wolves that lack the mutation, because the article did not mention anything about this.
Another concept that I find interesting is the question of "When does a mutation become a normal trait?" In other words, if an entire species carries the mutation then is it still a mutation?

Period 2_Kanishka said...

I really liked this article because you hardly ever read a story about a domesticated animal being helpful for a wild animal. I think the article makes really important points about how all changes in a species comes from mutations and how certain characteristics are helpful in certain environments.
I think Marika brings up a good point. Is a mutation situational? or is it still called a mutation even when it has become "part of"
the species' genes?

period1carlos said...

I find this to be very interesting, but not too surprising. I’ve always been confused of what a species is and troubled by the fact that there is no hard and fast distinction between different species. It feels only natural that the lines between several distinct species that can interbreed would blur. I wonder if, under the current classification system (which, even for its flaws, if very good) it might be more appropriate to created a new species for black wolves that have inherited the color gene from domesticated dogs. Of course, this would encounter the problem that those black wolves freely associate, breed, and are bred by white wolves. Because of this, it perhaps modern wolves as a whole (or all the species amongst them that can have black fur) should be considered distinct species from their ancestors who did not have dog genes.

Period1Gelsey said...

It is very interesting that dogs and wolves interbreed often enough to have one trait pass between them. It raises the issue about the definition of a species. If wolves and dogs can still interbreed after thousands of years of so-called separation, are they really different species or are they more closely related than we believe?

It's also ironic that the dark-skinned wolves are the ones with the natural immunity to skin infections. In a society where those with dark skin are often made inferior and assumed to be less "fit" to survive, the wolves and dogs show that this is not true.

The issue of what it means to be a mutation versus being part of the organism's dna is also interesting. If you trace back through the evolution of all living creatures, we all evolved from one common ancestor after many, many mutations. But would we still call these changes mutations? The simplet bacteria don't have eyes or appendages, but these are the norm for most animals. How do we limit the distinction between mutation and hereditary gene?

Gelsey and Danielle (there aren't enough pcs)

Period 1 Virginia said...

Before the article mentioned the mutation's immunity to viral skin infections, I assumed that the darker color of the wolves' skin helped them hide from their prey better in the dark forest than on the bright white tundra. The scientists in the article mentioned the immunity almost as an afterthought which makes me think that perhaps there are other benefits (since viral skin infections don't seem like a huge issue). I also was curious about the issue of cross-breeding. If a dog and a wolf produce offspring together, would the hybrid prefer to mate with one species over another? Would it just mate with the species it has the genes most similar too (in which case its different every time) or is one species preferred over the other?

Period 1 Chloe P-C said...

I agree with Carlos- this article made me question the line between the two different species. If dogs and wolves can interbreed, and live in the same general area, wouldn't they be considered subsets of the same species? I thought it was interesting, though, that mutations from domestic dogs would benefit their wild counterparts. Like Jenn, I thought it was really interesting that something like skin color could provide protection from viral infections. But this made me think: will these beneficial mutations eventually overtake the entire wolf population? Will the "pure" wolf species be phased out for dog-wolf hybrids? I wish the article had speculated on this a little more, because, as gray wolves are classified as endangered, I think it's a very important issue: are we willing to let endangered wolves slowly disappear? Should we interfere with evolution or let nature take its course?