Dog Smart

Lilah_face

“I used to think my human was smart, but I now realize he only looks that way.

I know I shouldn’t be anthropomorphic about one I’m particularly fond of.”

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Did you ever suspect that dogs often turn out looking like their owners—or the other way round?

…the portly owner of a British bulldog…the old lady with a blue rinse and a coiffed poodle in her arms…the greasy-haired young man in a leather jacket leading a pair of snarling pitbull terriers… Yes they are caricatures, but we have all seen them. And now there’s research to prove an association.

Lance Workman has been collaborating with the British Kennel Club to find out if there is any correlation between dogs and their owners for what psychologists call the “big five” personality traits—openness, conscientiousness, extroversion, agreeableness, and anxiety. After analyzing questionnaires returned by 1,000 pedigree dog owners Workman concluded, “We go for dogs that are a bit like us, just as we go for a romantic partner like us.” The breed predicted its owner’s personality: owners of working dogs were more extroverted, hound owners more emotionally stable, gun dog owners more affable, and toy dog owners were “an open and imaginative bunch.”

It makes sense if our dogs resemble us in some ways because either we chose the dog or it chose us. People domesticated them thousands of years ago because they are smart animals that can share a slice of our emotional lives. We sometimes overestimate them, treating our pets like cute little hairy people. I don’t think it’s wrong to hold that attitude because they are more likely to be the lucky ones showered with love and care from their owners. It is when we underestimate their intelligence and emotions that they are more likely to be treated shabbily. I used to visit an old farmer from New York who contradicted me when I explained the rich emotional life I have with our golden retriever. “It’s only a dog,” he’d say. But I still believe I am nearer the truth because I live closer to the animal.

Of course they have a wide range of abilities and personalities: smart ↔ dumb, placid↔aggressive, et cetera.  Dogs bred for working or hunting are generally at or near the top of the scale, except for poodles (no airheads). We like to be praised for owning a smart dog, as if it reflects on our own brains. It’s safer not to mix compliments like, “For a dumb breed he’s a magnificent specimen,” to a chow chow owner.

Some animal behaviorists used to deny that dogs have much emotional life. That seems ludicrously false to dog owners and is now contradicted by modern research (Ádám Miklósi, Dog Behaviour, Evolution, and Cognition). The controversy now centers on what emotions they can express. Love of their owner, joy at greeting a friendly face, and fear of punishment are all transparent emotions which they never conceal as we sometimes do. Expressions of love almost overwhelm some dogs, like the black lab greeting the soldier returning after six months deployment. If we say that a dog only loves when it is rewarded, is that so very different to the bonding of human hearts by more subtle rewards?

Perhaps the fame of Pavlov’s experiments gave some people the impression that dogs are little more than furry automatons. But we too learn automatic responses to coupled stimuli, including salivation to the sound of a dinner gong like the conditioned reflex in his dogs. Dog training and learning, and a good deal of human education, is owing to associations made between a voluntary behavior and a reward or punishment. The stock example is giving your pet a treat for returning a ball, which psychologists call ‘operant conditioning’.  That’s how working dogs, Grace and other smart dogs are trained to look so brilliant.

A really big brain isn’t needed to express the basic emotions like love, joy, and fear, but it helps build a larger repertoire. I carried out a simple experiment on my three-year-old golden retriever to test her learning ability, but she educated me.

dog intelligence

“Be patient, I’ll figure it out”

Taking advantage of her high motivation for food, I prepared three empty crème brûlée dishes. I wiped the insides with her favorite treat, peanut butter, so she couldn’t tell which concealed the reward. I turned each dish upside down, and stuck a US postage stamp on the one containing the blob of peanut butter. Then I lifted each in turn to show her where it was, and finally switched their positions in her plain sight. The experiment was repeated over and over ending up with different positions.

When I gave the release command she knew there was a reward at stake. We would have gone immediately to the dish labeled with the stamp, but she nosed each dish in turn again and again. Finally she came to the right answer. It is possible that despite my efforts the dish hiding the treat had a stronger odor than controls, but I think her strategy was to check her olfactory bulb first and hippocampus second.

Dogs trust their noses and ears more than their short-term memories which are not as sharp as ours. This is certainly a carry-over over from wolf ancestors, but dogs have a unique stock of behavior and an emotional intelligence that has been molded by domestication. Over the generations the two have been apart, gene expression in the hypothalamus has diverged which might explain differences in emotions and hormonal and autonomic responses.

Of the more complex emotions I’m sure dogs can express jealousy because ours proves it every time we walk together. She protests by jumping and barking when a neighbor’s dog pays me too much attention. Charles Darwin, a dog-lover, had no doubt “that a dog feels shame” (The Descent of Man, 1871). And when dog owners were polled recently, half of them believed their dogs can express grief and guilt. Judging by the viral video of Denver the dog who stole kitty cat treats guilt is written all over his expressive face video. But animal behaviorists look for other explanations, although none are as entertaining as guilt.

There is no doubt that dogs really care what we think of them, and they are amazingly sensitive to our body language. John Bradshaw, who studies dog behavior in Bristol, England, says that “at present, then, there has to be considerable doubt about whether dogs can actually experience an emotion similar to our guilt”. Perhaps we do misinterpret a low wagging tail and avoidance of eye contact, which may be conditioned by their anxiety to please us.

So they may be reacting to our behavior instead of an internal feeling. It is imponderable how much self-awareness a dog has, but perhaps not a great deal. They live very much in the present and we can confuse them by punishment after the fact.

If dogs have weak powers of reasoning and learn mainly by trial and error that doesn’t make them stupid. They have impressive powers of recall and skill retention. Theirs is a different kind of intelligence, and if we make much of the confusion we cause each other by sending misleading signals between the sexes we ought to admit greater misunderstanding of our pets.

Our golden was right. Her expectations of me were too high, because her owner is both smart and stupid. But he is trying to do better.

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Our Mutual Friend

What species has been domesticated for thousands of years, lives in our homes, helps to feed us, comes in different strains (‘pedigrees’), was one of the first to have its genome sequenced, and has limited alcohol tolerance—like us? I’m not thinking about one of our furry friends, but we would soon miss it.

I was musing about yeast while the breadmaker pounded dough to a low drumbeat in the kitchen. We don’t normally regard yeast as a companion species, but it has been with us longer than dogs or cats. It has had a much greater impact on human culture than either of them, and all because of the peculiar way it generates energy for life—by fermentation.

This is one of the first processes we learnt about in biochemistry class, and one of the simplest. Yeast cells possess an enzyme (zymase) that converts 1 molecule of glucose into 2 molecules of ethyl alcohol and 2 of carbon dioxide. Alcohol and gas are just waste products to these cells, but gifts of the gods to us. We have been harnessing fermentation to make bread and drinks for thousands of years before we figured out how it worked. The transformation of a heavy lump of dough into a light loaf of bread or a cloudy ‘must’ of grape juice into wine seemed miraculous to our ancestors.

And wine that makes glad the heart of man…and bread that strengthens man’s heart (Psalm 104)

The man or woman who first discovered fermentation has gone unrecorded, although archeological relics suggest it was in Egypt and the Middle East thousands of years ago, perhaps in Neolithic times. Like a number of great discoveries, the breakthrough probably came not to someone searching for a better bread or drink, but to a quick-witted person whose curiosity was aroused by changes in a lump of uncooked dough and a jug of fruit juice left out in the warm. Instead of discarding them, as most of would, he or she watched the natural experiment develop and tested the product. It was good. They had no notion about the underlying biochemistry, and it took a long time to realize that the process that raised dough and fermented juice were the same.

France’s greatest 19th Century scientists were engrossed with the process because the wine industry struggled for vintages of consistent quality and that didn’t spoil. Their names come straight out of textbooks—Lavoisier, Gay-Lussac, Cagniard de la Tour, and above all Louis Pasteur.

It is hard to put ourselves in the mind of people who until fairly recent had no clue that fevers, ‘fluxes,’ and biological decay are caused by microscopic organisms. Yeast, bacteria, and sperm (‘animalcules’) first came into view under the simple microscopes invented by the draper of Delft, Antoni van Leeuwenhoek. That was two centuries before Louis, the genius who unveiled the world of tiny things and announced a ground-breaking germ theory of disease.

He had an uphill struggle. Many fellow scientists were unconvinced that fermentation is caused by living cells, and they don’t need oxygen to ‘breathe.’ It was thought to be a purely chemical process, and the debate grew bitter with Justus von Liebig, a German chemist who can be claimed to be the Father of Marmite (concentrated yeast, see Post March 23, 2013). When knowledge is familiar and deeply-rooted it’s hard to understand there was ever a contrary view. It seems obvious that yeast is a living thing. Poured into a lukewarm sugar solution you can see them generating gas bubbles from ‘breathing.” Bake them in bread and they die. Transfer a few into a vat of nutritious fruit juice and the broth soon ‘boils’ (Latin fervere, hence fermentation).

The domestic and industrial applications of these energetic little friends are endless. As a dietary supplement yeast is unrivaled as a source of B complex vitamins. Yeast fermentation is used to make other liquors: kumis from milk/ kombucha from tea/ kvass from rye/ soy sauce, tauco and doenjang from soybeans/ root beer from sassafras (until it was declared carcinogenic and replaced). It didn’t matter if the alcohol content was low so long as there were bubbles. Fermentation of cereals looms large for manufacturing biofuel so our automobiles can run on 10% alcohol. Yeasts are used as low cost bioremediators to mop up pollutants like, including copper, zinc, nickel, and arsenic in groundwater and ponds. They even render safe the explosive TNT!

But our friends, domesticated baker’s and brewer’s yeast, have shadier relatives that also like to find a sweet place to call home. Yeasts spread by air or contact can spoil foods and on our bodies they have a particular fondness for orifices. If our immune systems did not protect us from pathogenic species we would soon succumb to them, and patients with weakened immunity need treatment with fungicides to protect them.

But when home bread makers get together the talk is positive, and only about the staff of

Home made bread

Half eaten, and it’s still warm!

life, exchanging formulas, and recommended suppliers of flour and yeast. Not all are loafers like me, happy to let a bread making machine do the hard work. Some of them love the exercise of beating dough, and a few use such violence that I wonder what is in their minds.

When two cycles of kneading and resting in the machine are complete I haul the dough out. I love how a sloppy mess of ingredients changes into an elastic, living ‘organism’ at blood temperature. I punch it down for a final rise (‘proofing’) in a baking tin before sliding it in a hot oven.

Bread making brings out the experimenter. My current favorite recipe for making a 2 pound loaf is:Bread recipe

It takes barely 15 minutes hands-on to make a loaf, but an eternity to cool enough for cutting the first slice.

Home made wine

Vintage label from our wine cellar

Alas, home wine making from berries (even grapes!) takes so much longer. I don’t have the patience. It was disheartening to open a vintage that was tenderly stored for a couple of years only to find it was contaminated with something that made it sour. Louis might have chuckled that I should have washed my feet before trampling fruit.

But if a recipe goes wrong I blame myself, not the yeast. Humans have shared life with yeast cells for thousands of years in a cooperative relationship that ecologists might call mutualism. We give them sugars to grow and they give us alcohol and bubbles in return. We are mutual friends.

Next Post: Dog Smart

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The Wolf Sharing my Fire

Lilah by firesideThere is something incongruous about the notion that the golden warming herself by our fire is still mostly wolf. It doesn’t fit her doggy nature. But how much shaggy wolf is still inside her remains a moot point.

They are members of the same species, share a common ancestor and have nearly identical DNA. However there have been ~20,000 years of domestication in the making of modern Max and Molly, which offered plenty of generations for molding their behavior and appearance. It really does matter how much wolf still hangs on in dogs because it affects attitudes and how we train them.

We all know what wolves are like, or thought we did, and will never forget the Grimm story of Little Red Riding Hood.

Little Red Riding Hood by Grimm

It is paradoxical that the closest relative of our best friend is one of the most reviled

Little Red Riding Hood

“All the better to see you with” Walter Crane (1845-1915)

creatures, an arch-enemy of farmers and shepherds, and the fount of so many myths and scary stories about blood-thirsty wolves and chimeric werewolves.

Even biologists held hard views about wolf society until recently. The pack was regarded as a hierarchy topped by an alpha male and an alpha female which claimed first rights to a carcass and kept discipline in the lower ranks. Peace was preserved by a mien expressing threats of aggression towards subordinates who responded with submissive gestures. This fierce portrait reminds me of feudal societies in which royals and nobles used to rule vassals by accepting homage in exchange for privilege. So inured are we to old assumptions about these animals that attitudes can resist the challenge of research throwing fresh light on their behavior.

The TV celebrity Cesar Millan evidently bases his dog training program on an outdated picture of wolves (The Dog Whisperer/ Leader of the Pack). If it seems unfair to use him as an example I’m sure he knows that being picked on is the price of winning public attention. He certainly deserves admiration for a talent in handling difficult animals and his endeavors to save and rehabilitate abandoned dogs. But he makes no apology for the conflict between his philosophy and science: “Once your dogs see you as their pack leader, the dog on dog aggression will stop as they stop fighting for dominance because you will be their calm-assertive pack leader.” He believes we must become accepted as leaders of our pets’ “pack.” Since dogs strive for dominance, we must firmly lay down rules and boundaries for them, otherwise we lose control. This disciplinary style has sometimes gotten him into hot water with humane societies, despite so obviously being an animal lover. Nevertheless there is surely a risk that this thinking can be used to justify the harsh and cruel treatment that dogs have suffered down the ages. The victims may not even understand why they are being punished.

Another TV presenter Victoria Stillwell (It’s Me or the Dog) trains dogs in almost the opposite way, as her website name implies, Positively. Her policy is to shower them with love and treats to reward good behavior, which we might call positive reinforcement. According to Victoria most trouble with dogs is their owners’ (our) fault, so we need at least as much education as they do. Sometimes a cameraman on her show catches the expression of a dog looking on “sympathetically” at its owner being grilled by the bossy Englishwoman.

Of the two views, Millan’s is harder to reconcile with the new understanding of wolf society. Extrapolation wolf→dog is becoming blurry.

Gray wolf

Gray wolf. Courtesy US Fish & Wildlife Service

Until recently wildlife researchers had to fall back on zoos for studying these animals. But in captivity packs are loose associations of individuals that seldom share a family history and live in confined spaces. It is not surprising in an artificial environment that animals are anxious and find ways to adapt behavior to avoid injury from those famous fangs. But we have probably misread some of their gestures, like the lowered head which was interpreted as submission to a supposedly superior wolf. This posture is actually an excellent position for grabbing the “boss” by its throat, but perhaps it had a friendly meaning and was cementing a social bond. We can’t be sure.

The new picture of wolf society has emerged from studies under natural conditions by tracking wolves wearing radio-collars and with GPS technology. Blood samples revealed genetic relationships within packs (L. David Mech & Luigi Boitani, Wolves: Behavior, Ecology and Conservation, Univ. Chicago Press). Contrary to impressions of a band of bushwhackers banded together under feudal leaders, a pack turns out to be just a family party. Its members are usually close relatives, and often former cubs that never split away from their parents. Sometimes an animal adopts the solo life, but they benefit from sticking together when there is big game to be had, like moose and bison.

We expect more cooperation than competition within families. Members are more loyal and less aggressive to each other, and the greater harmony boosts success in hunting and breeding and avoids danger and injury. Consequently more genes are contributed to the next generation to shape evolution of the species, as predicted by kin selection theory. Besides, no dominance hierarchies have been found in wolf packs apart from the relationship between Dad, Mom, and their offspring. Nor should we expect to find them in dogs. When they go wild, they never become wolf-like in behavior or jostle to create a hierarchy, although they can form a fractious group. There appears therefore to be no teeth to Cesar Millan’s belief that successful dog training requires us to fill in for the tough alpha wolf depicted in old stories.

If we think we know dogs I suspect that familiarity often blinds us to the marvel and mystery of our furry companions. While their wolf cousins are afraid of us and terrified of fire, dogs are comfortable with both. Sociobiology theory rules out altruism in animals and caring for the welfare of others unless they are genetically related, but there are remarkable examples of untrained dogs that have saved lives at their own risk (see Hero dog drags another dog to safety).

John Bradshaw, a British biologist, explains Dog World by taking us back to the origin of the canine family about five million years ago (Dog Sense, Basic Books). The Swiss Army knife is his metaphor for the genome of “proto-dogs.” Flexibility enabled their descendants to spread across six continents and evolve into many species of jackals, foxes, coyotes, and wolves. Perhaps it was this adaptability, he argues, that made domestication from wolves possible, and the emergence of an animal with greater loyalty and willingness to please us than any other.

I was musing about dogs while Lilah was dozing at my feet and sharing heat from logs on the fire. She opened an eye to check I was still there. It wasn’t an anxious look waiting for instructions from her alpha male: she was only looking at her “dad.”

Next Post: Our Mutual Friend

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Groundhog Day

My groundhog day will arrive when the raider of our strawberry patch sits in the cross-hairs of my sights. Last year the little ‘hog’ grazed it to the ground, leaves and all.

A neighbor over the fence told me he often sees our groundhog padding across his yard towards our back forty. I imagined the critter was a little larger than a guinea-pig with a snub nose, but my friend stretched out his arms.

“Whoa, that’s a giant!” I guessed it was a fisherman’s tale, but apparently not. After a

snow tracks

Groundhog, rabbit and deer tracks in the snow

heavy snowfall Tuesday night I found his broad tracks mingling with those from rabbits and deer. Evidently, our raider was on the rampage again, even while his northern relatives are still curled up in hibernation to give gardeners and farmers a break—all the critters except one.

There is a groundhog that has made the little Pennsylvania town of Punxsutawney famous. To other nations, it is a mystery why a country with a long history of hunting and extirpating animals devotes a whole day to Groundhog, which falls after Martin Luther King Day and before Presidents’ Day. It could only happen in a nation of animal lovers.

Phil boasts more titles than any European royalty, but his celebrity status rests on a reputation for being the only true weather forecasting groundhog. On Groundhog Day, he emerges from his burrow to be presented on stage at Gobbler’s Knob in front of his

followers and TV cameras. There he informs his Inner Circle of grim-faced men in black frock coats and top hats about the weather for the next six weeks. If Phil sees his shadow winter weather will continue; if he doesn’t see it we can expect an early spring. It’s a question that everyone is interested in after bitter weather from the polar vortex.

The tradition was brought to the USA by immigrant farmers from Germany where badgers were the seers. According to an old proverb: The badger peeps out of his hole on Candlemas Day and, if he finds snow, walks abroad; but if he sees the sun shining he draws back into his hole.

Predicting the last day of frost and higher ground temperatures has always been important for spring planting, and farmers often looked to nature for wisdom—when animals came out of hibernation or the thickness of their fur coats or the crop of winter nuts and berries. You can see why people thought these were signs, but not how they work. But perhaps when anticyclones are ‘parked’ for days or even weeks over the continent in winter, which creates calm, clear and cold weather, people associated the sunshine and shadows cast by them with continuing cold. At least that’s my theory for Punxsutawney Phil.

CandlemasGroundhog Day coincides with Candlemas mid-way between the winter solstice and spring equinox. The day was probably marked in pagan calendars, later becoming a Christian Feast Day when candles were blessed in churches like a festival of lights and when it was time to predict the change of season.

If Candlemas Day be fair and bright

Winter will have another fight.

If Candlemas Day brings cloud and rain,

Winter won’t come again.

Phil’s reputation suffers when his predictions turn out wrong, but how can one groundhog predict the weather across all the climatic zones of a continent? Minneapolis and Miami are totally different. I decided to check his record over the past five years at the closest major weather station to his burrow—Pittsburgh PA. As a Pittsburgh Steelers fan I think he’d approve my choice.

The average temperatures for February and March in 2009-11 and 2013 were all rather cold, although he only saw his shadow in two of the four years. And after he saw it again in 2012 the following two months were 10°F warmer than normal. Looking further back, he seems to have been right 50% of the time, which is what you’d expect for a binary choice by a statistically astute groundhog.Groundhog forecast

Like traditional weathermen and almanacs, Phil’s reputation is based on a long history of record-keeping. He announced his first forecast in the long winter of 1887-88, and is undisputed as the oldest groundhog in the world. Most of his kind survive no longer than 6-8 years in the wild (hopefully less in my yard), but his longevity is owing to a secret elixir that he sips at his summer picnic to keep him young. When you notice his coat color has changed from grey and grisly to brown and sleek you know that he has been rejuvenated again, which is more times than Doctor Who of the British TV sci-fi series.

Shortly after dawn this morning, Phil’s big day arrived. He faced followers who had temporarily forgotten about the Superbowl. Soon enough we were told that he had seen his shadow, so there are six more weeks of winter ahead. Quite how he managed to see his shadow on a rainy morning with cloud cover down to 400 feet mystifies me. Oh well, it’s just a bit of fun!

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Scavengers

Charles Dickens

Gaffer Hexam and Lizzie fishing for corpses on the Thames.
Charles Dickens: Our Mutual Friend. Clarendon edition, 1864

“Half savage as the man showed, with no covering on his matted head, with his brown arms bare to between the elbow on his shoulder, with the loose knot of a looser kerchief lying low on his bare breast in a wilderness of beard and whisker, with such dress as he wore seeming to be made out of the mud that begrimed his boat, still there was business-like usage in his steady gaze” (Charles Dickens: Our Mutual Friend).

Scavengers get a bad rap. In Dicken’s story, Gaffer Hexam and his daughter Lizzie made a living from scavenging corpses floating in the Thames. They rummaged pockets for valuables before giving the bodies up to the authorities. But one day he found a body with papers identifying it as John Harmon, a missing man, and Gaffer was accused of his murder. Living in squalor and in thickets of thieves, scavengers soon fall under suspicion of crime.

In Tudor England a skawager was a customs collector (a more honorable occupation today, although it still causes sinking feelings in a traveler waved to their desk). Over time, the word scavenger emerged as the name for any kind of street cleaner. In removing waste and carrion they performed useful services, although it was not realized until mid-Victorian times that they were helping to safeguard the public from epidemic diseases.

I remember scavengers when I was growing up in London. Those so-called “totters” were easily recognized with their horse and cart and hand bells or from their ringing voices,

“Rags and bones! Rags and bones!” We didn’t have much household waste in the 1950s

because post-war austerity still held a vice-grip on domestic budgets. Most of our stuff was collected by “dustmen” (garbage collectors), but some choice items were saved for the rag-and-bone man, like the remains of the Sunday roast joint which we were told would be rendered by some miracle into glue or soap. Children liked to stroke the horse stamping outside their homes while the man loaded his cart, but their parents often called them indoors until the ragamuffin went away.

In the BBC sitcom, Steptoe and Son (1962-74), Harold and his irascible father Albert are in the business together, although not in any other sense together. Harold aspired to a better life, deriding Albert as “a dirty old man,” but his pretensions to middle class respectability in a rag-and-bone yard always let him down, especially with women. We laughed at the show from the comfort of our living room, and the comedy crossed the Atlantic to become Sanford and Son. It is harder for the Millennial Generation to understand the rag-and-bone trade because, after four centuries of keeping our streets cleaner and freer of disease, it had almost vanished by 1980. Its last representative in London, Alf Masterson, died in 2007.

Animal scavengers don’t enjoy any better reputation than rag-and-bone men. Hyenas, raccoons, rats, flies, dung beetles, et cetera are all regarded as vermin. And although birds are more generally loved than most other animals, vultures are regarded with particular loathing.

Riding the thermals, vultures are aerial marvels that catch the slightest uplift even on cold days; and to watch a condor hanging over the Colorado River in the Grand Canyon is a memory to savor long after the vacation. In the eastern and southern USA turkey vultures and black vultures patrol the countryside from several hundred feet scouting for carrion

turkey vulture

Turkey vulture.
Courtesy: Virginia Master Naturalists

with their sharp eyes, although it is often the turkey vulture’s exceptional sense of smell that catches the first savory whiff of a meal. Where it dives its brethren quickly follow. Black vultures are the more sociable of the two species, but both are intelligent like that other carrion-eating family, the crows, but vultures are more reviled. The sight of a venue (the collective noun for a vulture gathering) around a carcass with their naked heads bobbing in and out of the gore looks revolting, although we don’t have the same reaction to the look-alike heads of wild turkeys. Baldness makes hygienic sense for this kind of diner, and it also helps to control body temperature in hot sun. Despite a scuzzy appearance, they are finicky about preening because their lives depend on their plumage.

black vulture swiping windshield blade

Black vulture – windshield wiper swiper.
Courtesy: Virginia Master Naturalists

These “buzzards” have become more common since the Migratory Bird Treaty Act (1918) which protects them from casual shooting, and they have spread north of the Mason-Dixon Line to breed in Canada. Perhaps they are responding to global warming, but certainly to food supplies.

According to the National Highway Traffic Administration the numbers of white-tailed deer have increased from half a million in 1900 to perhaps 15-20 million today, and many of them stalk suburban gardens and public parks close to roads. Every year 1.5 million vehicular accidents with deer are reported, which cause 150 human fatalities on average, 10,000

dumpster

vulture feeding station

injuries, and a billion dollars in costs. Vultures have often cleaned the road-kill before a highway maintenance crew arrives to dispose of the carcass. They are not always so welcome, particularly at landfills and around dumpsters backing onto schools and shopping centers, but they always provide services gratis.

Vultures in India and Pakistan are not faring so well, and some are in crisis. Populations have crashed by 98% from consuming carcasses of livestock treated with the anti-inflammatory diclofenac. Despite bans on the veterinary drug, their numbers have not bounced back and the costs of losing these scavengers are tragic and still being counted. Carrion often carries disease organisms normally destroyed in the guts of vultures but which survive passage through feral dogs and rats, which become carriers and spread rabies, anthrax, brucellosis, plague, and dangerous strains of E. coli. Bites from these animals are now even more serious, and carcasses left to rot contaminate water supplies, adding to human misery and fatalities. The Parsi (Zoroastrians) mourn the vultures that used to consume their dead relatives in funeral rites, and we should grieve the loss for many reasons.

The habits of vultures have barred them from ever becoming symbols of a nation, although the American bald eagle is a part-time scavenger. Sometimes an eagle can be seen crouching over road-kill, and even in vulture company. Benjamin Franklin was unhappy when the bald eagle was chosen for the Great Seal of the USA, and in 1784 wrote his daughter Sally:

Ben Franklin

Benjamin Franklin on $100 bill

“For my own part I wish the bald eagle had not been chosen the representative of our country. He is a bird of bad moral character. He does not get his living honestly…too lazy to fish for himself… (but) the turkey is in comparison a much more respectable bird, and…though a little vain and silly, a bird of courage, and would not hesitate to attack a Grenadier of the British Guards who should presume to invade his farm yard with a red coat on.”

If the ways of bald eagles made them ill-suited to be national symbols the British lion is also a national embarrassment. But many top predators—lions, tigers, white sharks, and even piranhas—will take carrion given an opportunity. And our prehistoric ancestors probably had few qualms about carving left-over flesh from beasts that were preyed on by other animals, which brings me back to our species as the top waste-maker and recycler.

Adam Minter, the son of a Minneapolis scrap dealer, describes how the humble rag-and-bone trade has evolved into a vast and hugely profitable industry (Junkyard Planet: Travels in the Billion-Dollar Trash Trade). Canny businessmen have always known that one man’s trash is another man’s treasure. In Our Mutual Friend, the corpse that Gaffer Hexam recovered from the murky Thames was misidentified as John Harmon, the heir to a fortune made by his estranged father from collecting garbage from London streets. That reminds me of a sage saying I often heard in Yorkshire, “Where there’s muck there’s brass (money).”

Thanks to friends at the Virginia Master Naturalists (Historic Rivers Chapter) for permission to reproduce images.

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