The Corpus Callosum

Susanne Sternthal, a writer based in Moscow, has published an article
about the ecology of stray dogs.  The article is in Financial
Times
, of all places.  Why is that?

href="http://www.ft.com/cms/s/2/628a8500-ff1c-11de-a677-00144feab49a.html">Moscow’s
stray dogs

By Susanne Sternthal
January 16 2010 00:04

…They also acted differently. Every so often, you would
see one waiting on a metro platform. When the train pulled up, the dog
would step in, scramble up to lie on a seat or sit on the floor if the
carriage was crowded, and then exit a few stops later. There is even a
website dedicated to the metro stray (www.metrodog.ru)
on which passengers post photos and video clips taken with their mobile
phones, documenting the ­savviest of the pack using the public
transport system like any other Muscovite…Where did these animals
come from? It’s a question Andrei Poyarkov, 56, a biologist
specialising in wolves, has dedicated himself to answering. His
research focuses on how different environments affect dogs’ behaviour
and social organisation. About 30 years ago, he began studying Moscow’s
stray dogs. Poyarkov contends that their appearance and behaviour have
changed over the decades as they have continuously adapted to the
changing face of Russia’s capital.

Poyarkov has identified different ecological niches, that are occupied
by different packs of dogs.  Each shares a characteristic set of
behaviors.  For example, the most socialized dogs:

Those that remain most comfortable with people Poyarkov
calls “guard dogs”. Their territories tend to be garages, warehouses,
hospitals and other fenced-in institutions, and they develop ties to
the security guards from whom they receive food and whom they regard as
masters.

One thing that interested me is the description of how dogs lose their
spots.  It turns out that domesticated dogs are more likely to
have spots.  Those that are evolving back to the wild lose the
spots.  Poyarkov attributes this to changes in the activity of the
href="http://www.cnsforum.com/imagebank/item/HPA_NORM_DPN_3/default.aspx">hypothalamic-pituitary-adrenal
axis (although this is not specified in the article).

i-35fd0588ecadfffb484318828b1486a7-HPA_NORM_DPN_3.pngWhat the article says is this:

…He began to select foxes that showed the least fear of
humans and bred them. After 10-15 years, the foxes he bred showed
affection to their keepers, even licking them. They barked, had floppy
ears and wagged their tails. They also developed spotted coats – a
surprising development that was connected with a decrease in their
levels of adrenaline, which shares a biochemical pathway with melanin
and controls ­pigment production.

“With stray dogs, we’re witnessing a move backwards,” explains
Poyarkov. “That is, to a wilder and less domesticated state, to a more
‘natural’ state.” As if to prove his point, strays do not have spotted
coats, they rarely wag their tails and are wary of humans, showing no
signs of ­affection towards them…

This is perplexing.  Adrenaline and melanin do not share a
biochemical pathway.  I have to infer what Poyarkov meant. 
He probably mentioned a peptide that serves as a precursor to various
hormones (although adrenaline is not one of them).  It probably is
pro-opiomelanocortin (POMC).  POMC is a peptide that can be broken
up into a variety of biologically active molecules.  A major end
product is adrenocorticotropic hormone (ACTH).  This stimulates
the adrenal glands, but not the part that produces adrenaline. 
Rather, ACTH stimulates the cortex, where steroids such as cortisol are
produced.  (Adrenaline is produced in the adrenal medulla, not the
adrenal cortex.)  Stress of many sorts will activate this system,
such that more POMC is produced, which leads to more ACTH, which leads
to more cortisol. 

Recall that I mentioned that POMC can be broken down into a variety of
biologically active molecules.  One of these is
α-melanocyte-stimulating hormone (α-MSH).  This, in turn, promotes
the development of melanin (not to be confused with melatonin). 
Melanin is what causes pigmentation of skin.  In some cases, a
stimulus that increases the production of ACTH will lead to an increase
in other products from the cleavage of POMC; hence, the increased
melanin.  (See href="http://medical.all-details.com/function-of-melanocyte-stimulating-hormone">this
link for a more detailed explanation.)

This, incidentally, is what causes some pregnant women to get a brown
stripe (linea negra) on their abdomens. 

Anyway, back to the alleyways of Moscow.

The grooviest of the Muscovite stray dogs are the Metro dogs:

“This began in the late 1980s during perestroika,” he says.
“When more food appeared, people began to live better and feed strays.”
The dogs started by riding on overground trams and buses, where
supervisors were becoming increasingly thin on the ground…”They
orient themselves in a number of ways,” Neuronov adds. “They figure out
where they are by smell, by recognising the name of the station from
the recorded announcer’s voice and by time intervals. If, for example,
you come every Monday and feed a dog, that dog will know when it’s
Monday and the hour to expect you, based on their sense of time
intervals from their ­biological clocks.”

I used to live next to a llama farm.  The guy who owned it urged
me to let him know if I saw any coyotes, and to make note of the time
and location.  He said the coyotes tend to show up at the same
time, in the same place, every evening.  He knew some guys with
night-vision rifle scopes, who would be happy to take care of the
problem for me.

I never called him.  The only time I saw a coyote, I took off
after it with a two-by-four. Never saw it again.  So much for that
theory.  I’d rather have a coyote around my house, than some eager
guys with high-powered rifles and night-vision scopes, anyway.

Sternthal then turns to a discussion of the question of whether Moscow
should make more of an effort to eradicate, or at least control, the
population of stray dogs.  This leads to perhaps the most
interesting ecological point:

Poyarkov believes this would be dangerous. While the goal,
he acknowledges, “is to do away with dogs who carry rabies, tapeworms,
toxoplasmosis and other infections, what actually happens is that
infected dogs and other animals outside Moscow will come into the city
because the biological barrier maintained by the population of strays
in Moscow is turned upside down. The environment becomes chaotic and
unpredictable and the epidemiological situation worsens.”

It is hard to predict what would happen, if the ecology were
perturbed.  That is the point.  History is littered with
examples of unintended consequences.  Ecological system are
complex, sort of like economic systems.  You “fix” them at your
own peril.

Poyarkov does not believe that the strays should be eliminated:

“I am not at all convinced that Moscow should be left
without dogs. Given a correct relationship to dogs, they definitely do
clean the city. They keep the population of rats down. Why should the
city be a concrete desert?

So why does the Financial Times publish a story about the
ecology of stray dogs in large, economically-distressed cities? 
Is this what the future holds for many large, urban areas?  Stray
dogs on the subway?  Should we all be getting night-vision rifle
scopes, or at least some 2×4’s?  No, but we may need to be
prepared for some serious epidemiological challenges.

Comments

  1. #1 stumpy
    January 22, 2010

    Why?

  2. #2 Newt
    February 8, 2011

    You’re trying too hard; the precursor is tyrosine; both adrenaline and melanin are synthesized from it. The implication is if you’re not using it for adrenaline, you have more for use elsewhere.

  3. #3 Orjin krem
    March 19, 2011

    So why does the Financial Times publish a story about the ecology of stray dogs in large, economically-distressed cities? Is this what the future holds for many large, urban areas? Stray dogs on the subway? Should we all be getting night-vision rifle scopes, or at least some 2×4’s? No, but we may need to be prepared for some serious epidemiological challenges.

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