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Monday, March 15, 2010

Domesticated Dogs--Mutualists or Parasites?

Photo courtesy of Dog Tag Art via Flickr

This thought exercise was motivated in part by my second reading of The Red Queen: Sex and the Evolution of Human Nature (by Matt Ridley) while on a trip to Argentina. The book covers parasitism's role in evolution. While in Argentina I noticed the stark difference between the urban mostly purebred lapdogs in Buenos Aries and the often malnourished mutts found in rural areas. Here are some Wikipedia links to the terms parasitism and symbiosis for reference.

Look at the picture of that blue-eyed, smiling beauty. Is that a smile? It's like the false eye patterns that have evolved on some moth wings. The false eye patterns are an illusion to scare off predators and just maybe that false smile is an illusion that works to tweak human emotions. The moth can't close its false eyes anymore than this dog can stop smiling. Dogs have evolved ways, both physically and behaviorally to endear themselves to us (elicit chemical reactions).

Most of us would not be best buds with another person who has bad breath and a tendency to pant while their huge dripping tongue hangs out of their gaping mouth, but dogs have to do that to regulate body temperature. Rather than evolve another way to manage body temperature, have some managed to get us to look past that rather unique and bizarre cooling system by placing a (simulated) smile behind it?

I'm not a dog hater. But I'm also not a "dog person." I consciously resist attributing more to a dog's behavior than is really there. The dog wants my resources but will do nothing to move my genes into the future in return for them (help me provide food and protection for my family), which is one definition of a parasite.

The dog will make me feel good the way a cigarette makes a smoker feel good (a case for tobacco plants manipulating us), whereas my natural affinity toward the opposite sex evolved specifically to move genes into the future. And of course dogs don't really consciously scheme in this way. The laws of mathematics and natural selection are simply moving things in this direction.

For 98 percent of our shared history, our relationship with dogs could be viewed as a form of mutualism, where both species benefited. This remains true where dogs are still used as biological burglar alarms, defenders of and even herders of livestock, and for hunting. All of these activities served indirectly to help move human genes into the future by helping to keep us safe and fed.

However, it's easy to see a trend, especially in cities, where dogs have lost most if not all of their usefulness when it comes to gene propagation (from an evolutionary perspective) and may actually be hindering human reproductive success. I'm not saying that is a good or bad thing. I'm just saying...

Clearly we have impacted dog evolution, and they have impacted ours although we tend not to notice or acknowledge that fact. Evolution is a response to our environment and clearly dogs have been a major part of that environment long enough to have impacted us genetically.

Most dogs today in first world countries are used almost exclusively for companionship. By companionship I mean the good feeling (chemical reactions) derived from the company of someone you like who also likes you. Feelings (chemical reactions) like that evolved in social primates to motivate the formation and maintenance of groups or monkey troops for mutual benefit.

Dogs are commandeering for their own gene propagation our companionship chemical pathways (feelings). Your dog is programmed to like his owner. The fact that everyone's pet dog seems to love its owner and vice verse is some evidence to suggest that this happens automatically, without conscious effort or thought--to like its owner regardless of who it is and for the dog owner to like their dog even if it is an ugly, snarling, stupid, untrained, hand-licking, crotch-sniffing, carpet-pooping, hair-shedding, smelly abomination. And that goes for cats as well:

My neighbor's cat--with summer hair cut

Given time, your dog would develop the same affinity with a new owner, and you with a new dog. This tendency probably evolved to enhance our past mutualism, but once this relationship evolves away from "mutual" propagation of genes, you have by definition, a parasite.

Grandparents can contribute mightily to the welfare of grandchildren, which may help explain our ability to live so long past our reproductive age. It's easy to see how a lapdog could not only divert physical resources from that role, but reduce the motivation to spend the time and energy to seek out those grandchildren by meeting those needs (feelings, chemical reactions) for those grandparents, especially now that most of us don't live in three generation households.

The antics of the grandparent's lapdog hanging out on a couch has become a ubiquitous stereotype and endless source of material for the TV show called America's Funniest Videos. These lapdogs might be viewed as genetically modified biological endorphin generators (tranquilizers).

Another ubiquitous stereotype is the guy in a pickup truck with his best friend hanging out the passenger window, a big (false) smile on his face, tongue flailing in the wind. Instead of a real person, man, woman, child, uncle, brother, parent, or in-law who might help care for or defend a family, you find a dog sitting there making his owner feel good inside. One could argue that chicks dig dogs and the dog will therefore attract a mate, but you can't argue that all chicks dig dogs. Chicks that do not dig dogs have been eliminated from that guy's list of potential mates the way cigarette smoking would have limited it. A tradeoff many smokers and dog owners are perfectly willing to make.

There is a trend among some street persons to keep a pit bull in their company, much to the chagrin of government officials and anyone else that feels obligated to cross to the other side of the street rather than cross a potential alcoholic, mental patient, or drug addict in possession of a dog bred to fight to the death.

And finally we have the young mom with her stroller and one, two, or three young kids along with two golden labs out for a leisurely stroll. Do those dogs add to the extensive energy and time required for child care? I have on more than one occasion seen parents who actually give deference to the family dog over their kids, within limits.

Most of today's lapdogs started out as hard working rat dogs, which today is considered a derogatory term. They were bred to chase and kill, and even to go into the burrows of various rodent pests, rats in particular.

Today, dogs bred to hunt bears, or foxes, or wolves, or game birds, or water fowl, or to herd and protect livestock, are caged up in cramped dark houses all day with nothing but a bowl of dried dog food and maybe a chew toy for company. They get to go outside on a leash twice a day to crap in a planter strip, or if they are really lucky, fill the backyard with their poop. Zoo animals have it better. What's wrong with this picture?

Dog owners quite simply rationalize away this grim reality so they can continue to get their fix. Their dog is ecstatic to see them when they walk through the door (after having spent the day alone in mind numbing isolation) and just look at that smile on his face!

The backyards in American cities are literally open sewers. This mountain of poop accounts for much of the degradation of bodies of water in and around cities. The news headline while I was in Buenos Aires was that a parasite spread by dogs had been found in the grass and soil of every park in the city.

Our dog and cat rescue and shelter facilities are bursting at the seams. Having saturated homes with rescue animals they have started rescue foster animal programs. It's starting to get ridiculous.

From an environmental perspective, consider keeping only lapdogs, dogs bred specifically as companion animals instead of larger, higher status breeds bred for other jobs. They did not evolve (albeit artificially) to live in a house environment. A dog's ability to elicit endorphin releases from your brain is not dependent on its size.

One environmental argument in favor of dogs is that a dog (poop issue aside) will do far less damage when substituted for children. That's a valid point but it also supports the contention that some dogs, by intercepting energy, resources, and feelings from owners, have moved from mutualist to parasite, which from an evolutionary perspective is neither good or bad, it just is.

Parasites, you gotta love 'em, or at least some of them.

[Update 5/9/2010] My eldest daughter pointed out that it has become popular for single young guys to own cute lapdogs, which she suspects are being used to get the attentions of women. If she's right, then using lap dogs as chick magnets would not qualify them as parasites ; )

[Update 11/21/2010] I watched a film called Dogs Decoded last night. Here is the transcript near the end of the show:

NARRATOR: But when we treat dogs as if they were children, do we sometimes allow them to replace our children?

MORTEN KRINGLEBACH: They are, essentially, moving our focus away from having children onto having pets.

PETER ROWLEY-CONWY: I think we can think of little puppies brought home as parasites. They don't do anything useful, they're not perceived as a food source, they're not perceived as a guard dog. They are simply brought home for fun.

The cuckoo is perhaps quite a good analogy because the baby cuckoo, of course, being planted in somebody else's nest, prompts mother bird to look after baby cuckoo, even though there's nothing in it for the mother bird at all.

MORTEN KRINGLEBACH: I think it's safe to say that dogs have, evolutionarily, been very successful. If you compare them to wolves, you will see that wolves are now an endangered species, while dogs, of course, are all around the world.

NARRATOR: Whether they are viewed as parasites or as beloved companions, no one can deny the evolutionary success of the domesticated dog.

In fact, there are over 400 million, worldwide. And humans have created over 400 genetically distinct breeds.

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  1. The "false" smile of which you write is also present in wolves, from which dogs were derived. I don't think dogs evolved expressions that were attractive to humans - these expressions were already coincidentally present in wolves. That coincidence was probably a big factor in their domestication and the development of dogs, but it doesn't mean that wolves [and dogs] evolved a "smile," or other expressions, in order to placate humans. Like much of natural selection, it was just chance.

    As an owner of two "working-type" dogs (who get plenty of exercise, I can assure you), I found your article interesting. What are your thoughts about evidence suggesting that dog ownership boosts overall health and happiness?

  2. Very good point about wolves and I suspected somebody might call me on it. Congratulations.

    If a study can show that dogs improve reproductive success then I will stand corrected : ).

    What age group do these health benefits extend to and do they lead to the survival of more human progeny?

    Cigarettes provide moments of happiness (defined as a measure of frequency of pleasure generating hormones) but happiness is not a necessary condition for gene propagation, in fact, it may get in the way of it.

    Just saying.

    And I appreciate the intelligent, civil comment.

  3. amazingdrx9:53 AM

    A dose of symbiotic thinking might be useful on this one bio-d.

    Imagine, if you will, a small tribe of humans, set upon by huge dangerous predators when they are trying to sleep. Then imagine a straggler from a local wolf pack, outcast, hungry, adopted by the tribe after he starts snacking on their leavings.

    The next time a big bear or cat attacks at night, their new wolf/dog friend warns them. The tribe gets their sleep, the wolf gets a new pack. Puppies are born and bond with their new tribe.

    Soon a well fed troop of dangerous friends are waiting with both nostrils open, while they sleep, awaiting any sign of trouble.

    The cats and bears learn to steer clear of the new tribe composed of humans and dogs. Soon, maybe after a few hundred years, the tribe learns to get a few herd animals, they can do that because thier dog friends are on guard.

    Evolution is symbiosis, much more complicated than stimulus/response calculations.

    I believe personally that raising a puppy from an early age, of both the child and the dog, makes that person better someday to be a parent, dogs teach empathy by example and much more.

    They teach kids to be alert, to tune into their surrounding and trust their instincts. Confidence, survival instincts, they should be out on the trail or the street watching and absorbing the way our ancient allies view the world.

  4. Good points, drx

    This is just a thought exercise. I'm not telling people they should not have pet dogs. They do offer many benefits, but not necessarily ones that lead to human gene propagation, or at least, they are much less effective at doing that than they once were.

  5. Human predators are even worse than ancient animals though, even worse than grizzlies, most would agree. Kids need what dogs teach about survival instincts now, just as ancient humans did.

    And the advantages of empathetic child rearing, especially in the crucial first few years, can't be stressed enough. Compare the offspring off genius IQ parents, that sits in front of the tv since birth (impossible you say? consider star parents who hire a nanny), to average IQ parents that have inspired their children with empathy and constant stimulation.

    That's what raising a puppy gives future parents, direct experience in the most successful techniques to have successful offspring. It's ancient learning from ancient symbiosis.

    I realize the trouble of having a dog in urban/suburban environments is annoying and energy intensive, but well worth it in terms of human evolution.

    Parasitic? Ahhouoxoxooohh, no way says Arnie, hehey. (click on my nick to see him)

  6. Anonymous1:55 PM

    Sorry to comment on an old article, but you said that happiness is not necessary for gene propagation and may get in the way of it?
    I agree happiness is not necessary per see, but how do you justify that assertion that happiness may get in the way on gene propagation when many studies have shown that chronic exposure to stress hormones have a negative impact on both male and female fertility?

  7. " do you justify that assertion that happiness may get in the way on gene propagation when many studies have shown that chronic exposure to stress hormones have a negative impact on both male and female fertility?"

    There is a very big range of hormone levels between suicidal depression and mania. The seeking of happiness is what moves genes into the future: friends (and allies), the love of a good spouse, children, grandchildren, food and on and on. If the pleasure of having a dog reduces the incentive to seek pleasure that leads to gene propagation, you have a parasite by definition. If having a dog facilitates baby making, then it doesn't fit the definition of a parasite. Your hypothesis is that dogs provide stress release, thus increasing fertility, making them into aphrodisiacs instead of parasites.

    Love to see a study to show evidence for or against either hypothesis. It's totally possible that dogs have the capacity to do both depending on the situation.


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