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Author Topic: Why are we (humans) not as varied in shape and size like dogs ?  (Read 10603 times)

Offline Seany

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Why are we (humans) not as varied in shape and size like dogs ?
« Reply #25 on: 11/04/2007 21:12:30 »
Pink poodles and an audio fair................cant resist!

In a Noel Coward double entendre stylee.


I'd love to be a pink poodle in panties,
and get stroked by my friends all day,
a lovely pink poodle in panties,
I wouldn't want it any other way,

With a diamond collar round my neck,
and a matrix by my side
playing with my bone,
that is sometimes hard to hide,

I'd love to be a pink poodle in panties
and play with my friends all day.

 :o

TMM



Lol :D
 

Offline JimBob

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Why are we (humans) not as varied in shape and size like dogs ?
« Reply #26 on: 12/04/2007 04:02:05 »
Any ideas what the ratio is to pure breeds to ' artificial' ones are ?

I assume there must be a ' foundation template' of a few thoroughbreds ?

Could the ratio be as high as i think it might ?.(Wild guestimate 80:20)........in that I expect there to be far more ' manufactured ' breeds than thoroughbreds !!......but what about other types of multi-variety animal ?

As far as I am aware, there is only one natural breed of dog, and that is the wolf, and everything else is an artificial breed.

Clearly, there is some variety amongst wolves, but none of that variety directly correlates to a modern breed of dog.

Trying to find a natural breed dog is like trying to find a natural breed of cow - no domestic animal is ultimately natural.

There are about 30 types of wild canines. The African Wild dog is obvious. But foxes are also Canines. There are 20+ species of foxes.  Here is what WIki.. says about the African dog:

"The African Wild Dog, Lycaon pictus also known as the African Hunting Dog, Cape Hunting Dog, or Painted Hunting Dog, is a mammal of the Canidae family, and thus related to the domestic dog. It is the only species in monotypic genus, Lycaon, and the only species in the canid family to lack dewclaws on the forelimbs. They are, as their name indicates, found only in Africa, especially in scrub savanna and other lightly wooded areas. The Latin name of the species means painted wolf and it is characteristic of the species that no two individuals have the same pattern of coat. Individuals can easily be recognized in the basis of coat patterns. The pelage is an irregular pattern of black, yellow, and white. Their coats are sparse in comparison to canids in temperate zones, and the skin is black."

 

Offline JimBob

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Why are we (humans) not as varied in shape and size like dogs ?
« Reply #27 on: 12/04/2007 06:32:09 »
Dang! DON'T FORGET THE COYOTE!

The coyote (Canis latrans, meaning "barking dog"), also prairie wolf, is a member of the Canidae (dog) family and a close relative of the domestic dog. In have seen one here in the city. Duh!

 

another_someone

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Why are we (humans) not as varied in shape and size like dogs ?
« Reply #28 on: 12/04/2007 09:57:02 »
Foxes are indeed a different species of the dog family, but as such, they cannot interbreed with domestic dogs.

Wolves can interbreed with domestic digs, and are thus not merely a different species of the same family, they are indeed the same species, but merely a different breed.
 

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Why are we (humans) not as varied in shape and size like dogs ?
« Reply #29 on: 12/04/2007 10:01:00 »
Coyotes DO interbreed with the common dog. They are also a different species.
 

another_someone

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Why are we (humans) not as varied in shape and size like dogs ?
« Reply #30 on: 12/04/2007 10:30:36 »
Coyotes DO interbreed with the common dog. They are also a different species.

This is where we get to ambiguities about species.

If cayotes can interbreed with the common dog (and I assume can also interbreed with wolves), the why are they regarded as a distinct species (except maybe out of tradition - the first guy who saw them regarded them as a distinct species, and nobody ever corrected him - but then, if an alien first saw a Chihuahua and a Great Dane, they would probably have regarded them as distinct species also - this is why I am always very sceptical about some of the counts used for the numbers of species that exist, and thus the number of species that become extinct.
 

Offline JimBob

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Why are we (humans) not as varied in shape and size like dogs ?
« Reply #31 on: 12/04/2007 11:12:26 »
Coyotes have a much different genetic make-up than dogs. Interbreeding is allowed because of gene number - when the zygotes are able in may cases to survive. Obviously, a horse and a donkey(ass)are different species. A donkey's coat is not waterproof. Asses are still found in the wild while horses are not. But these two different species can interbreed. The result is a donkey. There is one known example of an artificial insemination cross between a lion and a tiger. Alpacas and Llamas have been interbreed by ranchers in order to obtain a finer type of wool on an animal larger in size than an alpaca. There are many other types of examples in nature where the meeting of two species has led to other species - corals, fish, etc.

But the point you make about what differentiates a species begs the question of are there other types of dogs. There obviously are, or the African Wild Dog would not be named as it is. Jackals are also closely related to wolves. They were domesticated - at least breed - by the Egyptians. And, if you look up wolf taxonomy, there are more than 17 different sub-species that are differentiated. None that share habitat with each other will interbreed. So what is a species? The American Red wolf, not listed in Wiki, is being driven out of it's habitat and going to extinction from competition with the grey wolf or plains wolf. If lack of interbreeding describes difference in species then there should be 17 + wolf species. Taxonomy today is dependent on genetic sequencing. I am no expert on sequencing so I cannot speak to genetic taxonomy. But the old idea of if it interbreeds, it must be the same species and if it doesn't interbreed it is a different species was dead in the early '80's.

 

another_someone

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Why are we (humans) not as varied in shape and size like dogs ?
« Reply #32 on: 12/04/2007 13:54:13 »
Coyotes have a much different genetic make-up than dogs. Interbreeding is allowed because of gene number - when the zygotes are able in may cases to survive. Obviously, a horse and a donkey(ass)are different species. A donkey's coat is not waterproof. Asses are still found in the wild while horses are not. But these two different species can interbreed. The result is a donkey. There is one known example of an artificial insemination cross between a lion and a tiger. Alpacas and Llamas have been interbreed by ranchers in order to obtain a finer type of wool on an animal larger in size than an alpaca. There are many other types of examples in nature where the meeting of two species has led to other species - corals, fish, etc.

Mules (the cross between a horse and donkey) does exist, but is sterile.  Male ligers and togons are sterile, although the females are fertile.  Clearly, in none of these cases can a cross be considered a viable branch of either of the parent species.

But the point you make about what differentiates a species begs the question of are there other types of dogs. There obviously are, or the African Wild Dog would not be named as it is. Jackals are also closely related to wolves. They were domesticated - at least breed - by the Egyptians. And, if you look up wolf taxonomy, there are more than 17 different sub-species that are differentiated. None that share habitat with each other will interbreed. So what is a species? The American Red wolf, not listed in Wiki, is being driven out of it's habitat and going to extinction from competition with the grey wolf or plains wolf. If lack of interbreeding describes difference in species then there should be 17 + wolf species. Taxonomy today is dependent on genetic sequencing. I am no expert on sequencing so I cannot speak to genetic taxonomy. But the old idea of if it interbreeds, it must be the same species and if it doesn't interbreed it is a different species was dead in the early '80's.

http://en.wikipedia.org/wiki/Red_Wolf
Quote
For decades, the Red Wolf has been indistinguishable genetically from either the Gray Wolf or the Coyote. The Red Wolf breeds with both species and may again be in peril as contact with other species in the wild resumes

http://en.wikipedia.org/wiki/Canis
Quote
Canis is a genus that includes several of the modern wolf and jackal species, including the Gray Wolf (Canis lupus) which is thought to be the ancestor of the Domestic Dog (Canis lupus familiaris). There are between 7 and 10 species, depending on the source that is used. The jackals used to be placed in their own genus: Thor, but that classification is never used now. Molecular evidence indicate that Cuon (Asiatic wild dog) is actually part of Canis. Other closely related genera are Lycaon (African wild dog) and, more distantly, Pseudalopex and other South American Foxes.

In other words, if the Wikipedia entry is correct, the African Wild Dog is more distant from domestic dogs than is the grey wolf - so the use of the term 'dog' in the name should not be regarded as any indication of taxonomic proximity.

While I agree that DNA is used to determine taxonomic relationships, but I am not aware that we are yet sufficiently advanced in understanding the DNA to determine species delineation (i.e. we can say that A is more closely related to B than to C, but I was not aware that from DNA alone we can yet say whether A and B are two breeds of the same species, or two distinct species - although in the case of the Red Wolf, it does seem that the DNA is so close to the grey wolf and the coyote, that it is on that evidence alone the same species).
 

Offline neilep

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Why are we (humans) not as varied in shape and size like dogs ?
« Reply #33 on: 12/04/2007 14:41:05 »
THANK YOU BOTH GEORGE & JIMBOB


This is very interesting.

Can a Chihuahua do  'the deed ' with a Great Dane then ?

Will the offspring be the same whether the Chihuahua is the mummy or daddy ?
 

another_someone

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Why are we (humans) not as varied in shape and size like dogs ?
« Reply #34 on: 12/04/2007 15:40:19 »
One of the problem with the idea of species is that it has become political.  If the Red Wolf is regarded as a distinct species, then you can claim protection for it as an endangered species, but if it is only regarded as a breed, then it loses that legal protection, and so the word you use has not only scientific significance but also political significance.
 

Offline Seany

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Why are we (humans) not as varied in shape and size like dogs ?
« Reply #35 on: 12/04/2007 15:42:11 »
*Nods head frantically*
 

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Why are we (humans) not as varied in shape and size like dogs ?
« Reply #35 on: 12/04/2007 15:42:11 »

 

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