Sunday, 9 December 2018

A test for breeding-back: the Tamaskan Dog

Two recent posts (The real differences between aurochs and cattle and Is genetic breeding-back possible) show the differences between wild and domestic, aurochs and cattle and also point out the limitations of “breeding-back”. Since the aurochs is extinct, it would be an interesting test for “breeding-back” to do exactly the same what we do with cattle (taking primitive individuals, crossbreed them and breed them selectively in order to approach the wildtype) but only with a species where the wildtype is still extant so that you can compare the outcome directly to it. Actually, this has been done already and the result is known as the Tamaskan dog. It is a dog breed that was created by crossing wolf-like dog breeds and selecting them towards a wolf-like appearance and the result is actually pretty good. Thus, the Tamaskan dog is a kind of “test” for “breeding-back” with cattle and therefore we are going to have a look at it today. 
(Actually, five years ago I already did a post on this subject but do not consider it not sufficient nowadays) 

History of the Tamaskan

First of all, we have to determine what the predecessors of domestic dogs were. I covered this question in this post, and evidence suggests it were basal members of the wolf species comparable to the Indian or Himalayan wolf, and not the Holarctic macropredatory wolf subspecies of the North. However, domestic dogs certainly had influx from local wolves everywhere, as cranial similarities between polar wolves and huskies[1] as much as the grey wolf-like appearance of breeds like huskies and German shepherd dogs suggest. We have a pretty similar situation as with cattle here: they originate from the near east, but had some influx of local aurochs elsewhere[2]. 
The Tamaskan dog breed originated in the UK and Finland in the 1980s. A couple of husky-like sled dogs were crossed with Siberian huskies, Alaskan malamutes and German shepherd dogs. The outcome was continuously selected for a wolf-like appearance. It was possible to achieve a rather wolf-like exterieur without any crossing-in of wolves or wolfdogs, only by crossing less-derived dog breeds and selecting for resemblance to the wildtype. The success in the case of the Tamaskan is pretty impressive. This is a Tamaskan: 
© hundeseite.de
For comparison, this is a Czechoslovakian wolfdog (which is a hybrid breed of German shepherd and wolf): 
Wikimedia commons
And this is a European grey wolf: 
Wikimedia commons
Looks and behaviour of the Tamaskan 

Tamaskan dogs have a withers height of 63-84cm in males and a body weight of 30-50kg according to Wikipedia. This is roughly identical to the measures of a European grey wolf. The colour is a little more variable than that of a grey wolf. In many individuals the colour scheme is almost identical to the typical colour of Holarctic wolves, . Also its proportions and body conformation is very similar to that of a wolf. Tamaskan dogs are slim and long-legged. Also the eye colour compromises only wolf-like brown tones although they are not quite as yellowish as that of many wolves. Overall you could easily mistake a Tamaskan for a grey wolf. So to say, the attempt to create a dog breed that looks like a wolf without any crossing-in of wolves was successful (unfortunately some breeders include wolfdogs in their breeding, what dilutes the Tamaskan as a “breeding-back” attempt). 

But taking a closer look you see that the Tamaskan is a dog. The head is somewhat larger and more domed, the snout is not as long and pointed but broader and more rounded and the eyes are larger (paedomorphy). And German shepherds have, as most domestic dogs do, proportionally smaller teeth, especially the fangs  – I assume that the same is the case with the Tamaskan. I would not be surprised if the Tamaskan also has a reduced acuity of senses, recognizable f.e. in the size of the auditory bullae in the skull, which found in any dog breed, even wolf-like ones like the German shepherd[1]. I found no sources claiming that Tamaskans take longer to mature or have a seasonal reproduction circle like wolves, so I assume that the developmental biology of these dogs is as domestic as that of any other dog. Also, some Tamaskans have a dewclaw that only domestic dogs have. 
While wolfdogs, which are hybrid breeds of German shepherds and wolves, have a recognizable different behaviour, Tamaskan dogs display a usual domestic dog behaviour. Czechoslovakian and Saarloos wolfdogs are more independent than usual dogs, shy to strangers, easier to scare, need early socialization, have a strong hunting instinct, are more enduring and remarkably good at tracing (Wikipedia), which is an obvious consequence from the influx of the wildtype. Tamaskan dogs seem to be no different in behaviour from the breeds it was bred from. It is simply a wolf-like dog breed like any other. Looking at videos, they appear very tame, friendly and trainable. Their behaviour is not comparable to that of a wolf in any respect. Here is a video of Tamaskan dogs on youtube: 

Thus the Tamaskan, although very wolf-like in overall appearance, has all the symptoms of the domestication syndrome: paedomorphy in morphology (especially skull morphology), reduced acuteness of senses, earlier maturity and loss of seasonal reproduction, tame and trainable behaviour with greatly reduced fight/flight reaction. 

I think the Tamaskan is very relevant for the way we should look at “breeding-back” cattle. I often had discussions on if we should call any cattle “rebred aurochs” or not. I would never call any cattle rebred aurochs, for reasons given in the posts linked in the first paragraph and some more. My question to those speaking of “rebred aurochs” is: would you consider the Tamaskan a wolf? Or a rebred wolf? Obviously the Tamaskan is not a wolf but a dog – their appearance is as wolf-like as can be but looking at the defining traits of a domestic dog, the Tamaskan is a dog in every respect. The same is the case with “breeding-back” results, however aurochs-like they may become in the future. It is up to you but in my opinion you also have to consider the Tamaskan a rebred wolf when you speak of a rebred aurochs. And this maybe shows how inconsistent it is to call “breeding-back” results rebred aurochs. 

Taking all the arguments of these latest three posts into account, the next post will cover the question: if we cannot achieve a true aurochs, what can we achieve with “breeding-back”? 

Literature 

[1] Koler-Maznik: Origin of the dog. 2002. 
[2] Park et al.: Genome sequencing of the extinct Eurasian aurochs, Bos primigenius, illuminates the phylogeography and evolution of cattle. 2015. 

2 comments:

  1. Well, the animal would look the same.
    And we know feral herbivores regress to wild herd type behaviour*, if left alone over multiple generations, as you have wrriten yourself.

    In conclusion, we'd end up with a bunch of big landrace cows that have gone native, adopt most of the same behaviours, and fulfill the same ecological niche as their ancestors, which is the best we can expect, given the circumstances(unless we find some ways to revive those beasts by finding a ton of aurochs DNA)

    *as a side-note, dogs also regress to something similar to their wolf-cousin ancestors, a feral forest packeven managing to bring down a bison in Romania

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  2. This is easily one of your best posts! Very enlightening and quite sober.

    Petter Bøckman,
    Norway

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