# Tasmanian Tiger Genetic Secrets Revealed



## kyektulu (Jan 13, 2009)

*Taken from BBC News:*

*Scientists have detailed a significant proportion of the genes found in the extinct Tasmanian "tiger".* 
The international team extracted the hereditary information from the hair of preserved animal remains held in Swedish and US museums. 
The information has allowed scientists to confirm the tiger's evolutionary relationship to other marsupials. 
The study, reported in the journal Genome Research, may also give pointers as to why some animals die out. 
The two tigers examined had near-identical DNA, suggesting there was very little genetic diversity in the species when it went over the edge. 
Although it was hunting that finally drove the Australian animal out of existence, its longevity as a species may already have been fatally compromised, the researchers believe. 
The lessons should not be lost on modern conservation efforts, the team says. 
"Looking at the genetic diversity in a population is a key marker for endangerment and it should be used to assess the urgency of preservation," Professor Stephan Schuster from Penn State University told BBC News. 
*Recurring theme* 
The Tassie tiger (_Thylacinus cynocephalus_) was dog-like in appearance and striped like a big cat - but in evolutionary terms, it had little in common with either, and was more closely related to kangaroos and koalas. 
Wild thylacines were present until the early 1900s; the last known captive specimen died in Hobart Zoo in 1936. 
Its recent demise, and the existence of several well-preserved specimens in museums, has led many to speculate that the animal might be the best extinct candidate for attempted resurrection through new molecular science techniques such as cloning. 
But the team behind the latest research says its motivation lies in a different direction. 
"Our goal is to learn how to prevent endangered species from going extinct," said Webb Miller, another Penn State professor and a member of the research team that includes scientists from the US, Sweden, Spain, Denmark, the UK, and Germany. 
"I want to learn as much as I can about why large mammals become extinct because all my friends are large mammals," Professor Miller added. 
"However, I am expecting that publication of this paper also will reinvigorate discussions about possibly bringing the extinct Tasmanian tiger back to life." 
*Clean signal* 
The team extracted DNA from the preserved hair of the tigers. This tactic has recently become a fruitful avenue of research. 
The DNA molecule will degrade over time, but the hair shaft's keratin material slows the decay and limits bacterial contamination. 
This same team used the approach to piece together about 80% of the genome of a woolly mammoth, a beast that disappeared several thousand years ago. 
"The hair is like a shrine for DNA," Professor Schuster said. "In bone you have millions and millions of porous channels, and micro-organisms can penetrate it very deeply; and when they die inside the bone, they deposit their DNA on top of the DNA of the animal. 
"In hair, the bacteria are mostly on the outside, and you can use protocols to decontaminate the hair and once you have done this, you resolve the material from the hair shaft and you retrieve the DNA that was stored on the inside." 
This latest research has identified the small set of genes found in mitochondria, the structures that power biological cells. The DNA in mitochondria is handed down from mother to offspring. 
Because it mutates at a stable rate, researchers can use it like a clock to time the divergence of species. By doing this, it is possible to show that the tiger's closest living relative is another marsupial called a numbat. 
*Devil concern* 
"The two thylacine sequences were extremely similar to each other, with only five differences in 15,492 nucleotides," Professor Miller further explained. 
The team says this level of similarity suggests that as the species neared extinction, there was too little genetic diversity to resist bacterial and other environmental stresses. 
Had hunting not taken out the last individuals, they would have been extremely vulnerable to disease, for example. "This is the danger of a clonal population," Professor Schuster said. 
"Low genetic diversity is appearing as a common theme in the extinct species being studied by our team." 
The team is now looking at the genetics of the threatened Tasmanian devil (_Sarcophilus harrisii_) whose remaining numbers are currently being ravaged by a transmissible facial cancer. 
Early research indicates genetic diversity in the devil is also very low. 
"We're trying to find the genetic differences between them, only this time around we would like to use this information for pedigree selection," Professor Schuster told BBC News. 
"We will tell the breeding efforts already under way in Australia which animals they have to breed to have the maximum success in stabilising the population, and to breed the most genetic diversity possible."


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## kyektulu (Jan 13, 2009)

Most interesting insights to the exctinction of the Thylacine, however the secrets revealed also add new hope to the success of ressurecting this amazing animal.
I for one prey this happens.


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## Ghost Of Gernsback (Jan 14, 2009)

kyektulu said:


> Most interesting insights to the exctinction of the Thylacine, however the secrets revealed also add new hope to the success of ressurecting this amazing animal.
> I for one prey this happens.


 
There is some very consistent evidence that the Tassie Tiger may not be extinct. Potentially there could be at least two breeding pairs in the wild


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## Dave (Jan 14, 2009)

The way I read that news article throws a different light on the announcement last week that we will soon be able to clone sabre-tooth tigers, mammoths and neanderthal men. We might be able to clone an individual organism at some time in the far future, but a viable population of those species would be out of the question on the genome of only a few individuals. Jurassic Park could never happen, based as it was, on a single blood sample.


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## Vladd67 (Jan 14, 2009)

The latest edition of New Scientist has this article
Ten extinct beasts that could walk the Earth again - life - 07 January 2009 - New Scientist


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## Moonbat (Jan 14, 2009)

> The latest edition of New Scientist has this article
> Ten extinct beasts that could walk the Earth again - life - 07 January 2009 - New Scientist


 
I read this, and the best bit was the super-giant armadillo, but it would have problems in that a surrogate giant armadillo wouldn't be able to bring the cloned infant to term before it burst out of her womb.


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## Creator (Jan 15, 2009)

Why don't they create an artificial womb?


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## Rosemary (Jan 15, 2009)

A very interesting article Kye.   Although almost yearly there is a claim that someone has seen a Tasmanian Tiger.

I'm not too sure I would want to meet a Woolly Mammoth though, Moonbat.  Interesting, just as long as they kept their distance....


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## Moonbat (Jan 16, 2009)

> Why don't they create an artificial womb?


 
I think the point of the article was that by unsing DNA from remains of animals, usually hair they could use a closely related living species to clone the extinct animal in that whole 'make an embryo add extinct DNA and chuck it in a living womb' type way.

I think I'd like to meet a wooly mammoth, maybe not alone in a small life, but definitely from afar at a nature reserve.


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## chrispenycate (Jan 16, 2009)

Dave said:


> The way I read that news article throws a different light on the announcement last week that we will soon be able to clone sabre-tooth tigers, mammoths and neanderthal men. We might be able to clone an individual organism at some time in the far future, but a viable population of those species would be out of the question on the genome of only a few individuals. Jurassic Park could never happen, based as it was, on a single blood sample.



The   lack of genetic diversity is more a symptom of a species going extinct than a cause. Several cases of species superbly adapted for a static environment dumping excess genetic material to increase energy efficiency have been recorded in extremely successful organisms, and this strategy works very well as long as there are no new factors introduced (like insecticides, since most of the beasts with a short enough generation for these changes to be observed have been arthropods). 

And how long would a dinosaur live? (or a mammoth, for that matter) For a theme park, comparing with other large reptiles, a breeding population might be unnecessary; indeed, in the book, they had deliberately eliminated this possibility. (and failed; but that doesn't change the fact they'd attempted to avoid breeding) As a zoo attraction, or equivalent commercial enterprise (even if it's a university department showing off how good their genetics section was) long term (multi-generational) success might well be irrelevant.


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## kyektulu (Jan 16, 2009)

Ghost Of Gernsback said:


> There is some very consistent evidence that the Tassie Tiger may not be extinct. Potentially there could be at least two breeding pairs in the wild



I know, Thylacines are a passion of mine and I research them enthusiasticly. I think this is the second Thylacines related threads I have done on here.

I strongly reccommend Cryptomundo for everyone interested in Cyrptozoology. 

Cryptomundo - for Bigfoot, Loch Ness, and More - Blog Home

Here are some 'videos' claiming sightings of Thylacines.

Cryptomundo » Thylacine Videos


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## kyektulu (Jan 16, 2009)

The second video I think is a fox with mange, my partner agrees with me but the second and third... I prey... such a magnificant animal it would be tragic if it truely is extinct.


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## Xelebes (Feb 8, 2009)

Vladd67 said:


> The latest edition of New Scientist has this article
> Ten extinct beasts that could walk the Earth again - life - 07 January 2009 - New Scientist



 A giant sloth would be awesome to see.


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