Archaeology has placed the earliest known
domestication of dogs approximately at 30,000 BC, and with certainty at 7,000 BC. Evidence suggests that dogs were first
domesticated in southern East Asia.
Due to the difficulty in assessing the structural
differences in bones, the identification of a domestic dog based on cultural
evidence is of special value. Perhaps the earliest clear evidence for this
domestication is the first dog found buried together with human from 12,000
years ago in Palestine and a burial site in Germany called Bonn-Oberkassel with
joint human and dog interments dating to 14,000 years ago.
In 2008, re-examination of material excavated from
Goyet Cave in Belgium in the late 19th century resulted in the identification
of a 31,700 year old dog, a large and powerful animal which ate reindeer, musk
oxen and horses. This dog was part of the Aurignacian culture that had produced
the art in Chauvet Cave.
In 2010, the remains of a 33,000 year old dog were
found in the Altai Mountains of southern Siberia. DNA analysis published in
2013 affirmed that it was more closely related to modern dogs than to wolves. In 2011, the skeleton of a 26,000 to 27,000
year old dog was found in the Czech Republic. It had been interred with a
mammoth bone in its mouth—perhaps to assist its journey in the afterlife.
Domestication of the wolf over time has produced a
number of physical or morphological changes. These include: a reduction in
overall size; changes in coat colouration and markings; a shorter jaw initially
with crowding of the teeth and, later, with the shrinking in size of the teeth;
a reduction in brain size and thus in cranial capacity (particularly those
areas relating to alertness and sensory processing, necessary in the wild); and
the development of a pronounced “stop”, or vertical drop in front of the
forehead (brachycephaly). Certain wolf-like behaviors, such as the
regurgitation of partially digested food for the young, have also disappeared.
Adapted from: http://en.wikipedia.org/wiki/Origin_of_the_domestic_dog
EOB-2....
How many of you are sitting there comfortably, looking at your "best friend" (the 4-legged one), wondering just which parts of your pooch bear the most resemblance to a wolf? There's no doubt that man's best friend has taken on a lot of different appearances and traits...however, genetic and archaeological evidence do provide a direct pathway from Canis familiaris (your "best friend") back to Canis lupus (the wolf).
How Dogs Evolved Into 'Our Best Friends'
Dogs have aided humans for thousands of years. Man's
best friend has provided protection, companionship and hunting assistance since
the days of the earliest human settlements.
But how and when dogs evolved from wolves is a
matter of debate. Naturalist Mark Derr says there are two main schools of
thought: Some researchers believe that humans domesticated wolves who were
scrounging around their villages for trash. Others think that humans were
taking care of wolves from the time they were puppies — until enough puppies
were tamed and they somehow then evolved into dogs.
"Neither explanation seems satisfactory,"
writes Derr in How the Dog Became the Dog — From Wolves to Our Best Friends.
"That is why there's no consensus."
In his book, Derr explores how the relationship
between humans and wolves developed, and how that relationship then influenced
the physical evolution of wolves into dogs. He tells Fresh Air's Dave Davies
that he believes humans and wolves developed a close relationship after
recognizing themselves in each other while hunting on the trail of big game.
"[That's when] they started traveling together,
and they've been at it ever since," he says. "The dog is a creation of
wolves and humans — of two equal beings that came together at a certain point
in history and have been together ever since."
Derr says our ancestors likely followed behind
wolves as they hunted for game on the trail. Wolves, in turn, learned to wait
for scraps from bipedal hunters — who were far more accurate with their
rudimentary weapons than the wolves were with their teeth.
The wolf could say, 'These people are far more
profligate hunters than we are. When they go out, they always leave a surplus.
It's easier for us to take the scraps that they have than to hunt,'" says
Derr. "Hunting is a highly energetic activity. And they could learn from
each other, just by observing each other."
As humans and wolves began to work and live
together, physical features on the wolf began to change: Its skeletal frame
grew smaller, and its jaw shortened. Wolves that socialized well with humans
began to travel with them, and then were able to pass on their genes.
"You had populations of dog-wolves that became
isolated, and in doing so, they began to inbreed," says Derr. "And
when you inbreed, you get genetic peculiarities that arise, and then those
peculiarities become part of the population. If they work or become popular or
have some function of beauty or utility, then they were kept by the humans —
and that population then spreads those through other populations through
breeding."
Fossils of wolves and dogs have been found in early
hunting camps. In China, researchers have found evidence that some hunters were
raising millet to feed to their hunting companions.
"This kept the dogs alive during times of thin
meat," says Derr. "When they weren't getting as much meat as they
wanted, they would feed [the dogs] millet. That would indicate that the early
dog was being used as a hunter, but also that it was highly valued."
On puppies
"There's something about them that makes us
friends with them. There are people who dislike dogs for sure. But dogs also
have an uncanny ability ... to walk in a room and pick out the one or two who
seem to dislike dogs the most and make friends with them. It's happened to me
with some of my dogs on numerous occasions. I think there's a deep — some
people call it love, I call it a 'deep empathy' between these two species that
resonates with each other in a way that makes them comprehensible to each
other, even though they don't speak the same language."
On small dogs
"There are some people who suggest that the
small dog, because of its size, was a curiosity, an easier dog to have as a
companion. In much of American history and even today, you'll find people who
have two dogs: a large dog, who is in the yard, and a small dog, whose job is
to kill rats and make a noise if somebody comes near, be a companion or
playmate for the children, or a guardian."
On the cultural evolution of dogs
"This is one of the reasons why people like to
speak of the dog as a separate species than the wolf, even though they're so
closely related. The dog lives with us in a way that wolves don't. It is
created by us in different ways."
On breeding
"I'll say it bluntly, and it has to be said:
Some of these breeds are incapable of giving birth without C-section. ... I
think that it certainly is wrong to produce animals that aren't healthy. It's
bad for the animal and bad for the people who take them into their homes and
find out that this dog they love is going to die at a very young age because of
an inheritable disease. ... We really should ask ourselves whether it is fair
to the animal to do that. I am of the opinion that it's not."
Adapted from: http://www.npr.org/2011/11/08/142100653/how-dogs-evolved-into-our-best-friends?ps=cprs
Dog:
man's best friend for over 33,000 years
He's
been man's best friend for generations
An
ancient dog skull found in Siberia and dating back 33,000 years presents some
of the oldest known evidence of dog domestication.
When
combined with a similar find in Belgium, the two skulls indicate that the
domestication of dogs by humans occurred repeatedly throughout early human
history at different geographic locations -- rather than at a single
domestication event, as previously believed.
"Both
the Belgian find and the Siberian find are domesticated species based on morphological
characteristics," said Greg Hodgins, a researcher at the University of
Arizona's Accelerator Mass Spectrometry Laboratory and co-author of a study
reporting the find.
"Essentially,
wolves have long thin snouts and their teeth are not crowded, and domestication
results in this shortening of the snout and widening of the jaws and crowding
of the teeth."
The
Altai Mountain skull is extraordinarily well preserved, Hodgins said, enabling
scientists to make multiple measurements of the skull, teeth and mandibles that
might not be possible on less well-preserved remains. "The argument that
it is domesticated is pretty solid," he said. "What's interesting is
that it doesn't appear to be an ancestor of modern dogs."
At
33,000 years old, neither the Belgian nor the Siberian domesticated lineages
appear to have survived earth's last ice age. Still, they show, just how far
back our special relationship with our canine companions goes, Hodgins said.
"The
interesting thing is that typically we think of domestication as being cows,
sheep and goats, things that produce food through meat or secondary
agricultural products such as milk, cheese and wool and things like that,"
he said.
"Those
are different relationships than humans may have with dogs. The dogs are not
necessarily providing products or meat. They are probably providing protection,
companionship and perhaps helping on the hunt."
"And
it's really interesting that this appears to have happened first out of all
human relationships with animals."
and….
To come
to the finding, a team led by Anna Druzhkova of the Russian Academy of Sciences
sequenced mitochondrial DNA taken from one of the skull’s teeth. This type of
genetic material comes from an organelle inside each cell called the
mitochondria, which has a distinct type of DNA that’s separate from the cell’s
normal chromosomes. For each individual, mitochondrial DNA is inherited
directly from one’s mother without any modifications and thus remains
relatively constant over generations, except for the gradual effect of
mutations. Similarities found in such DNA collected from various animals helps
scientists understand the evolutionary relationships between species.
The
research team compared their sample of mitochondrial DNA from the ancient skull
with samples from 70 different modern breeds of dog, along with 30 different
wolf and 4 different coyote DNA samples. Their analysis found that the fossil’s
DNA didn’t match any of the other samples perfectly, but most closely resembled
the modern dog breeds, sharing the most similarities with Tibetan Mastiffs, Newfoundlands
and Siberian Huskies in particular.
Scientists
know that dogs evolved as a result of the domestication of wolves, but the
specific time and location of this domestication is still poorly understood—and
this discovery further complicates that picture. Most experts agree that dogs
predate the invention of agriculture (which happened roughly 10,000 years ago),
but some say that domestication may have occurred as long as 100,000 years ago.
This
finding—and the previous radiocarbon dating of the skull which established its
age—set that event to at least 33,000 years ago. However, dogs may have been
domesticated from wolves multiple times, and this breed of Siberian dog may
have actually gone extinct, rather than serving as an ancestor for modern dogs.
Archaeological evidence indicates that, with the onset of the last glacial
maximum (around 26,000 years ago), humans in this area of Siberia may have
stopped domesticating dogs, maybe due to food scarcity. In that case, an
independent domestication elsewhere may have led to the dogs of today.
On the
other hand, domestication in the vicinity of the Altai Mountains, as evidenced
by this finding, may have led to the geographic spread of dogs elsewhere in
Asia and Europe, even if they died out in Siberia. Previously, many have
suggested that the first domestication occurred in the Middle East or East
Asia, but this skull could force scientists to rethink their theories. The
research team behind the analysis notes that finding more ancient dog remains
will help us in putting together the puzzle.
Why
Dogs are More Like Humans Than Wolves
Brian
Hare began studying dog intelligence as an undergraduate at Emory University in
the 1990s, after realizing that Oreo, his Labrador retriever, had a remarkable
ability. Unlike other animals, even chimpanzees, Oreo could interpret human
gestures, following a person’s gaze or a pointing finger. From early
experiments with the family dogs in his parents’ Atlanta garage, Hare went on
to found the Canine Cognition Center at Duke University. Now, in The Genius of
Dogs: How Dogs are Smarter than You Think, Hare and coauthor Vanessa Woods
detail recent research about man’s brilliant best friend. Not only do dogs
possess social intelligence far beyond that of their wolf ancestors, Hare says,
but in many ways they’re more like us than our own primate relatives. Hare is
also the lead scientist behind Dognition.com, a new website that offers pet
owners the opportunity to participate in a massive citizen science project—and
uncover the genius in their own precious pooches.
What is
the secret to dogs’ intelligence?
The
genius of dogs is that they use probably the most powerful tool on Earth to
solve problems—humans. At one point in wolf evolution, a group of wolves
decided to take advantage of humans, and they have been really successful
because of it. It’s probably not a surprise to people that dogs are socially
tuned-in to us. But I think what’s new is the understanding that this skill is
absolutely remarkable in the animal world. When you talk about survival of the
fittest, most people think nature is “red in tooth and claw.” But dogs domesticated
themselves through a natural process, where the less aggressive, most friendly,
tolerant individuals actually did much better.
How has
the scientific understanding of dogs changed?
We’ve
learned more in the past 10 years than in the previous 100 years. When
identifying intelligence in animals, what people are most interested in is
where animals make inferences. These are situations in which they can’t
actually perceive a solution, so they have to infer it spontaneously. If you
are going to find that kind of intelligence, you’re not going to find it in a
dog, or so it was thought. Scientists had theorized that dogs, through
domestication, have become dumbed-down, because they just sit around and take
scraps from us. What do they need to be smart about? The guess was animals like
a bonobo or a dolphin or other charismatic megafauna were where to look. But it
turns out in many ways dogs are more like us than even great apes.
How are
they like us?
Dogs
are the only species that have demonstrated that they can learn words in a
manner similar to a little kid. It’s not that other species that we think of as
being highly intelligent, like bonobos and dolphins, can’t become sophisticated
at communicating using symbols, but there’s some nice evidence that dogs are
using an inferential strategy, which takes advantage of what’s called the
principle of exclusion. They know that a number of objects are named or labeled
with a sound, and when a new one is introduced that they do not have a label
for, and they hear a new sound that they’ve never heard before, they infer that
the new sound must apply to this new object. That has only been observed in
human children before. That was a big shocker, and it’s been replicated. It
even gets crazier than that—several border collies are using what’s called the
principal of iconicity. You can show them a two-dimensional picture, and they
will then go fetch the object in the picture. That’s something people thought
only kids could do, and that it would only be in a linguistic species that that
would be possible.
That’s
amazing, but it’s a small sample size—isn’t it possible these dogs were
outliers?
We
don’t know. I don’t think it’s chance that the dogs that have demonstrated this
are border collies. But that is not to say that border collies are somehow the
most intelligent breed. All dogs are probably able to make the type of
inferences that the border collies are making. The question is, can they use
that exclusionary principle when learning words? It’s entirely possible that all
of our dogs have this hidden talent that we just don’t know how to take
advantage of.
What
are some other new findings about dog intelligence?
There’s
a lot of research into how dogs solve problems. For instance, in a new
experiment, a dog demonstrated opening a sliding door, using one of two
techniques. It turns out other dogs will copy the first dog and use that same
technique the very first time they open the door. That is not something that
most people would have expected. [A hundred years ago, British psychologist] C.
Lloyd Morgan was one of the first people to write about animal intelligence
from an experimental perspective. One of the great anecdotes he tells is about
how his dog Tony struggled to open a gate, and through trial and error, he slowly
learned a solution. It looked like Tony the terrier was a genius, but because
Morgan had watched the problem-solving develop, he knew that Tony didn’t
understand anything, that it was all chance trial and error. Morgan then
concluded that when you see animals doing intelligent things, you must consider
that there’s a very low-level mechanism that allowed them to solve the problem.
But the new finding is, if he had only shown Tony how to open the gate, Tony
could have learned almost immediately how to do it. You make the problem social
and dogs do fantastically.
You
also cite studies that show dogs can be deceptive. How does that demonstrate
genius?
Those
studies show that dogs are using information about what humans can see or hear
to make decisions about how to behave around us. In one study, dogs
spontaneously avoid retrieving food from a box with noisemakers when they have
been told not to eat it, [instead choosing to steal food from a box that a
human has demonstrated does not make noise]. This suggests they might be aware
of what we can and cannot hear. Similarly, a number of studies have shown that
dogs avoid misbehaving if you are watching them, but are more likely to act up
if you have your back turned, or even your eyes closed!
So
there is such thing as a bad dog. But can this new science of dog cognition
help us train them better?
No pun
intended, I don’t really have a dog in the fight about how to train dogs, but
it’s an important question. People love dogs, and they want to help their dogs
have a rich life, and they can do that by helping their dogs obey some simple
principles. But how do you get a dog to do that? One of the big schools of
thought is you have to really be an alpha dog. You have to make sure the dog
doesn’t think he can boss you around. That premise is probably based on some
faulty rationale, that dogs evolved from wolves, and wolves have a very strict
hierarchy. That’s a reasonable hypothesis, except that there’s one major
problem: dogs are not wolves. Looking at feral dogs, what people have found is
that they don’t have a strict hierarchy. It’s not that you follow the dominant
individual. With feral dogs, the leader is the individual that has the most
friendships in the group. It’s not about dominance.
There’s
another school of training, which says that the more you practice the better
they’ll be at sitting, staying, listening to you, obeying, etc. But there are
studies that show that dogs that are trained less intensely actually learn
faster and retain the information they learn longer. If you force animals to
perform over and over, it actually makes a response less flexible.
Here’s
a question that could get us in trouble. Are dogs smarter than cats?
It’s a
very difficult question to answer in any meaningful way. I could ask you, which
is a better tool, a hammer or a screwdriver? They’re designed to do different
things. Compare the origins of these animals in the wild, their progenitors,
the wolf and the wild African cat. You have one that is an endurance runner, a
pack animal that relies on cooperation. You have another that is a relatively
asocial, stalking hunter that relies on stealth to be successful. These are
completely different social systems and ways of life, and evolution shaped
those minds to be really different because they do completely different things
in terms of how they make a living.
Fair
enough. In addition to dog and cat partisans, I’m guessing that many pet owners
will have another response to your book: “There’s no way my dog is a genius. He
drinks out of the toilet and chases his own tail.” Would these people be wrong?
Everybody
loves to talk about how amazing humans are as a species in terms of innovation
and technology. We’ve invented the Internet and the iPad, and we have an
International Space Station. Yes, as a species we’ve done that, but I can
assure you that if somebody said to me today, “You have to invent the next
iPad,” you might as well just shoot me. There’s also tremendous individual
variation in dogs. In the case of the dog that chases his own tail, that may be
a dog that the person thinks is a little bit on the dumb side, but there are
some domains of intelligence that people aren’t really thinking about. Just
because one individual dog isn’t particularly good at using gestures, for
example, it doesn’t mean that they’re not absolutely remarkable in their
memory, or that they can’t use your visual perspective to deceive you. One of
the things we’re trying to do in the book is change the conversation about what
is intelligence. A lot of people may find out, the dog that just chases his
tail, there’s actually a lot more there than they expected.
Adapted from: http://www.smithsonianmag.com/ideas-innovations/Why-Dogs-are-More-Like-Humans-Than-Wolves-192083131.html?utm_source=smithsoniansciandnat&utm_medium=email&utm_campaign=201302-science
OK, now, be honest...how could anyone even think that either one of these cuties could have descended from a pack of wolves???
OK, now, be honest...how could anyone even think that either one of these cuties could have descended from a pack of wolves???
Any questions or comments should be sent to Helpful Buckeye at: dogcatvethelp@gmail.com or submitted at the "Comment" section at the end of this issue.
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Boy that little Blackie is cutier than a Junebug! :^)
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