Thinking Doggie-Style
Has our long shared history with dogs shaped their brains - and ours?
By David Hambling
December 2010
Photo by Etienne Gilfillan
FT271
A common – if unlikely – claim made by dog owners is: “He understands every word you say.” But scientists are increasingly finding that it might be truer than you think. The evidence suggests that the two species have moulded each other over a long period of co-evolution, and have developed sophisticated communications in the process.
Archæological findings show that dogs were first domesticated at least 10,000 years ago, with one find at the Goyet Cave in Belgium recorded in 2008 possibly pushing that back to 30,000 years. Genetic studies indicate that the process of domestication that split dogs from wolves may date as far back as 100,000 years. And the relationship may have started long before that, as some archæological finds put humans and wolves in the same place 400,000 years ago.
The aptly named biologist Wolfgang Schleidt suggests that the two came together in Northern Europe at a time when humans – either Homo sapiens or the earlier H.erectus or H.heidelbergensis – existed in small nomadic groups. Humans joined wolves in their following of migratory reindeer, and the two races of hunter-scavengers started working together.
The success of the wolf pack hinges on the members’ ability to work together without conflict and share the kill. Recent work with dogs shows that they have a sense of ‘fair play’, previously thought to be limited to primates. The experiment at the University of Vienna involved training dogs to extend a paw. The dogs were happy to perform this trick with or without a reward when on their own. But if they were with another dog which received a reward when they did not, the dogs quickly refused to play.
We don’t know yet whether wolves share this attitude. Some have suggested that dogs became attuned to fairness as an adaptation for living with humans. This seems questionable: the phrase “a dog’s life” dates back to the 17th century, meaning “a life of misery, or of miserable subservience”.
Perhaps humans gained their own notions of fairness from their companions during the period when the two worked together. Wolfgang Schleidt suggests that “wolves and dogs, with their remarkable capacity for co-operation and loyalty, were both role models and companions on this long trek toward humanity.”[1]
Sherlock Holmes once noted the curious silence of a dog, which failed to bark in the night (clear evidence to the great detective that an intruder was known to the dog). However, what is really curious is that dogs bark at all. Barking is rare among wolves, whose vocal communications are generally howls or growls. Barking appears to have been evolved to talk to people.
Barking is more effective at getting human attention than growling. Peter Pongracz, a behavioural biologist at Eotvos University in Budapest, has shown that the pattern of barking is different for aggression, loneliness and happiness. Pongracz’s team recorded hundreds of different barks from different situations. Not only were the barks consistently different depending on the dog’s emotional state, but even people who had never owned a dog were able to correctly interpret them. Our long association with them means that understanding dogs is hardwired into the human psyche.
Humans and dogs also share the ability to follow a gaze or gesture to see what someone else is looking at or indicating. This is very unusual in nature – even chimpanzees have trouble with pointing tasks. However, the same team at Eotvos University also showed that dogs are capable of following both gaze and pointing. This should not come as any great surprise when you consider what Pointers are bred to do. Wolves are also capable of learning the same tricks, but it is much harder for them: unlike dogs they are not used to looking at humans.
Again, it would be interesting to know if pointing or gaze-following is a natural skill in wolves that humans – being mere primates and a bit slow – gradually acquired over time.
Dogs also read human facial expressions. A team at the University of Lincoln has found that dogs show what is termed ‘left gaze bias’. This is the tendency, when looking at a human face, to look left (i.e. at the right-hand side of the face) first, and to spend more time looking at this side. Left gaze bias has already been established as a human trait and only occurs when looking at faces. The reason for it is that emotions register more clearly and more intensely on the right side of the face. And dogs have been around humans long enough to have face-reading in their genes.
However, while it might seem that dogs and humans have evolved to understand each other very well, there is one huge gap. Children under the age of five have very little understanding of dog body language or barks and can’t tell a happy dog from an angry one. An excited child may try to hug this big fluffy toy, with disastrous results. Dogs and small children should always be supervised; possibly ancient humans didn’t leave children alone with dogs the way their modern descendents are prone to. Or perhaps evolution still has some work to do.
So far, research into dog-human communication has only scratched the surface; but the indications are that, even if they don’t catch every word, dogs understand us very well indeed because they shaped our brains as we shaped theirs.
NOTES
1 WM Schleidt: “Apes
This is a journal of sorts. A compilation of thoughts, dreams, ideas and misfortunes. This is a collection of experiences shared with people that I've met as well as a walk through this world of mine. This is also a collection of interesting things I've seen or read on this wonderful world we call the internet.
Thursday, September 29, 2011
Thinking....Doggiestyle
Saturday, September 10, 2011
Do dogs recognize death?
Last night as I was walking the two hounds, Xerxes and Emmy, we happened upon the corpse of a raven. This is the story of what happened during that 4 minute adventure.
Xerxes was the first to spot, approach and sniff the carcass. The bird was laying prostrate on it's back, talons clenched. Xerxes approached with apprehension and gingerly sniffed, ready to spring back at a moments notice. He sniffed the dead bird an moved on.
Emmy, on the other hand, showed a great deal of apprehension and caution. She crept over carefully, ready to spring back...but with even greater fright, as if she was approaching something quite dangerous. Finally she sniffed the corpse once and that's when the surprise kicked in. Emmy started nosing pine needles over the body in a very delicate and ginger manner. She very carefully and thoroughly covered the bird in pine needles, maneuvering herself all the way around the critter to do so. Only after the bird was completely buried did Emmy walk away from the raven.
Why is this event unusual, one may ask. It stood out in my mind because I have been reading a great deal about self-awareness, consciousness, language and even the recognition of death among different species of animals. So this event leads me to the questions:
What was the purpose of this burying behavior?
Was Emmy saving this bird for a future meal?
Did Emmy recognize that the bird was dead and in decay, thus needing to be covered to prevent other scavengers from entering the area?
Why was Xerxes reaction completely different than Emmy's reaction?
Were her actions altruistic? Was she showing some sort of inter-species respect for this animal? (She has encountered dead and dying squirrels before and never performed this behavior.)
Xerxes was the first to spot, approach and sniff the carcass. The bird was laying prostrate on it's back, talons clenched. Xerxes approached with apprehension and gingerly sniffed, ready to spring back at a moments notice. He sniffed the dead bird an moved on.
Emmy, on the other hand, showed a great deal of apprehension and caution. She crept over carefully, ready to spring back...but with even greater fright, as if she was approaching something quite dangerous. Finally she sniffed the corpse once and that's when the surprise kicked in. Emmy started nosing pine needles over the body in a very delicate and ginger manner. She very carefully and thoroughly covered the bird in pine needles, maneuvering herself all the way around the critter to do so. Only after the bird was completely buried did Emmy walk away from the raven.
Why is this event unusual, one may ask. It stood out in my mind because I have been reading a great deal about self-awareness, consciousness, language and even the recognition of death among different species of animals. So this event leads me to the questions:
What was the purpose of this burying behavior?
Was Emmy saving this bird for a future meal?
Did Emmy recognize that the bird was dead and in decay, thus needing to be covered to prevent other scavengers from entering the area?
Why was Xerxes reaction completely different than Emmy's reaction?
Were her actions altruistic? Was she showing some sort of inter-species respect for this animal? (She has encountered dead and dying squirrels before and never performed this behavior.)
Thursday, September 08, 2011
Why some Languages Sound So Fast
SOURCE
Slow Down! Why Some Languages Sound So Fast
By Jeffrey Kluger Thursday, Sept. 08, 2011
Read more: http://www.time.com/time/health/article/0,8599,2091477,00.html#ixzz1XMPaNWb8
Here's one of the least-interesting paragraphs you've ever read: "Last night I opened the front door to let the cat out. It was such a beautiful night that I wandered down to the garden to get a breath of fresh air. Then I heard a click as the door closed behind me."
OK, it becomes a little less eye-glazing after that, with the speaker getting arrested while trying to force the door back open. Still, we ain't talking Noel Coward here. All the same, this perfectly ordinary passage and a few others like it are part of an intriguing study just published in the journal Language — a study that answers one of the longest-standing questions about human speech.
(Read why speaking more than one language may delay Alzheimer's.)
It's an almost universal truth that any language you don't understand sounds like it's being spoken at 200 miles per hour — a storm of alien syllables almost impossible to tease apart. That, we tell ourselves, is simply because the words make no sense to us. Surely our spoken English sounds just as fast to a native speaker of Urdu. And yet it's equally true that some languages seem to zip by faster than others. Spanish blows the doors off French; Japanese leaves German in the dust — or at least that's how they sound.
But how could that be? The dialogue in movies translated from English to Spanish doesn't whiz by in half the original time, after all, which is what it would have to do if the same lines were being spoken at doubletime. Similarly, Spanish films don't take four hours to unspool when they're translated into French. Somewhere among all the languages must be a great equalizer that keeps us conveying information at the same rate even if the speed limits vary from tongue to tongue.
To investigate this puzzle, researchers from the Universite de Lyon recruited 59 male and female volunteers who were native speakers of one of seven common languages — English, French, German, Italian, Japanese, Mandarin and Spanish — and one not so common one: Vietnamese. They instructed them all to read 20 different texts, including the one about the housecat and the locked door, into a recorder. All of the volunteers read all 20 passages in their native languages. Any silences that lasted longer than 150 milliseconds were edited out, but the recordings were left otherwise untouched.
(Read about the death of a language.)
The investigators next counted all of the syllables in each of the recordings, and further analyzed how much meaning was packed into each of those syllables. A single syllable word like "bliss," for example, is rich with meaning — signifying not ordinary happiness but a particularly serene and rapturous kind. The single syllable word "to" is less information-dense. And a single syllabile like the short i sound, as in the word "jubilee," has no independent meaning at all.
With this raw data in hand, the investigators crunched the numbers together to arrive at two critical values for each language: The average information density for each of its syllables and the average number of syllables spoken per second in ordinary speech. Vietnamese was used as a reference language for the other seven, with its syllables (which are considered by linguists to be very information dense) given an arbitrary value of 1.
For all of the other languages, the researchers discovered, the more data-dense the average syllable is, the fewer of those syllables had to be spoken per second — and the slower the speech thus was. English, with a high information density of .91, is spoken at an average rate of 6.19 syllables per second. Mandarin, which topped the density list at .94, was the spoken slowpoke at 5.18 syllables per second. Spanish, with a low-density .63, rips along at a syllable-per-second velocity of 7.82. The true speed demon of the group, however, was Japanese, which edges past Spanish at 7.84, thanks to its low density of .49. Despite those differences, at the end of, say, a minute of speech, all of the languages would have conveyed more or less identical amounts of information.
"A tradeoff is operating between a syllable-based average information density and the rate of transmission of syllables," the researchers wrote. "A dense language will make use of fewer speech chunks than a sparser language for a given amount of semantic information." In other words, your ears aren't deceiving you: Spaniards really do sprint and Chinese really do stroll, but they will tell you the same story in the same span of time.
None of that, of course, makes the skull-cracking business of trying to learn a new language any easier. It does, however, serve as one more reminder that beneath all of the differences that separate Tagalog from Thai from Norwegian from Wolof from any one of the world's 6,800 other languages, lie some very simple, very common rules. The DNA of speech — like our actual DNA — makes us a lot closer to one another than we think.
Read more: http://www.time.com/time/health/article/0,8599,2091477,00.html#ixzz1XMPGjmF2
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