Some good news for a change:

Tasmanian devils are developing resistance to the devil facial tumour disease, potentially saving themselves from extinction, new research has found.

The international study, published today in the journal Nature Communications, looked at tissue samples taken from Tasmanian devils at three sites across the state over a 17-year period.

Researchers have identified genetic changes in the mammals that are associated with fighting cancer.

University of Tasmania’s School of Biological Sciences Associate Professor Menna Jones said it was a significant find.

“The main result of this study is that the devil is evolving at a genomic level,” she said.

“The regions that are changing in response to the disease are those that are associated with cancer and immune function.

“It indicates that the devil is adapting, it’s responding to the disease in ways that it may be able to beat the cancer and save itself.”

The devil facial tumour disease is a transmissible cancer that was first discovered 20 years ago.

Since then, the devil population has declined by more than 80 per cent.

Researchers expected the species would build a resistance to the cancer, but were surprised at how quickly the devils were adapting.

Full report: http://www.abc.net.au/news/2016-08-31/tasmanian-devils-developing-cancer-resistance/7798338

This is interesting.

It would seem that, if this is the case, the “insurance population” approach, where very young individuals are removed from the wild to be bred in a disease-free environment, to be released once they become extinct, must be counter-productive. .

The Species is bouncing back, good to hear the news.

Speedy said:

This is interesting.

It would seem that, if this is the case, the “insurance population” approach, where very young individuals are removed from the wild to be bred in a disease-free environment, to be released once they become extinct, must be counter-productive. .

I wouldn’t say counter productive. It’s a measure used commonly these days as a ‘go to’ if viable.

Speedy said:

This is interesting.

It would seem that, if this is the case, the “insurance population” approach, where very young individuals are removed from the wild to be bred in a disease-free environment, to be released once they become extinct, must be counter-productive. .

the staff involved in the program predicted almost all of the stock, when released, would end up squashed on the road..

they weren’t wrong…

the tumor was not present in any of the captive populations (ie zoo populations) I suppose that will make them weaker than their surviving wild cousins

Arts said:

the tumor was not present in any of the captive populations (ie zoo populations) I suppose that will make them weaker than their surviving wild cousins

That’s what I meant by counter-productive.

I understand that, given the info. at hand, it was the only realistic approach at the time. Hindsight can be a terrible thing.

It is, however, yet to be seen whether this new “resistance” is enough to prevent extinction of the wild population.

> published today in the journal Nature Communications

This also made it onto tonight’s ABC3 news, channel 23.

Good on you, Channel 23.

In other news on ABC3 tonight, a localised reversal of coral bleaching.

Speedy said:

Arts said:

the tumor was not present in any of the captive populations (ie zoo populations) I suppose that will make them weaker than their surviving wild cousins

That’s what I meant by counter-productive.

I understand that, given the info. at hand, it was the only realistic approach at the time. Hindsight can be a terrible thing.

It is, however, yet to be seen whether this new “resistance” is enough to prevent extinction of the wild population.

To do nothing and take the gamble that the devils might develop immunity, is a very big gamble on this species survival. If the captive species are released back into the wild once the cancer is no longer active, then it is possible that it will not be passed on, plus their offspring (coupled with the immune devils) have a good chance of receiving the immune genes. Therefore, to save some devils as a safeguard was a positive thing to do, plus may assist in reviving their numbers more quickly.

PermeateFree said:

To do nothing and take the gamble that the devils might develop immunity, is a very big gamble on this species survival. If the captive species are released back into the wild once the cancer is no longer active, then it is possible that it will not be passed on, plus their offspring (coupled with the immune devils) have a good chance of receiving the immune genes. Therefore, to save some devils as a safeguard was a positive thing to do, plus may assist in reviving their numbers more quickly.

Yes.

I read somewhere that this species’ genetic diversity is poor due to the last ice age. They are on a slow road to extinction regardless of any facial tumour cure.

Ancient genes may explain modern threat to Tasmanian devils

http://sydney.edu.au/news/84.html?newsstoryid=10698

Speedy said:

Ancient genes may explain modern threat to Tasmanian devils

http://sydney.edu.au/news/84.html?newsstoryid=10698

The low gene diversity could just show there has been little need for the devils to change, or they have not been impacted by new dangers. With evolution if there is no need to change, then species seldom will, or do so very slowly.

Many native species have suffered badly from new diseases since European occupation that were largely brought about by environmental change and the alien flora and fauna they brought with them.

Speedy said:

PermeateFree said:

To do nothing and take the gamble that the devils might develop immunity, is a very big gamble on this species survival. If the captive species are released back into the wild once the cancer is no longer active, then it is possible that it will not be passed on, plus their offspring (coupled with the immune devils) have a good chance of receiving the immune genes. Therefore, to save some devils as a safeguard was a positive thing to do, plus may assist in reviving their numbers more quickly.

Yes.

I read somewhere that this species’ genetic diversity is poor due to the last ice age. They are on a slow road to extinction regardless of any facial tumour cure.

Poor genetic diversity, I hadn’t thought of that. Poor genetic diversity coupled with large numbers (like humans) sometimes indicates an explosive and unsustainable increase in population numbers. Makes me wish that Devils had survived on the mainland. That would have increased the generic diversity.

mollwollfumble said:

Speedy said:

PermeateFree said:

To do nothing and take the gamble that the devils might develop immunity, is a very big gamble on this species survival. If the captive species are released back into the wild once the cancer is no longer active, then it is possible that it will not be passed on, plus their offspring (coupled with the immune devils) have a good chance of receiving the immune genes. Therefore, to save some devils as a safeguard was a positive thing to do, plus may assist in reviving their numbers more quickly.

Yes.

I read somewhere that this species’ genetic diversity is poor due to the last ice age. They are on a slow road to extinction regardless of any facial tumour cure.

Poor genetic diversity, I hadn’t thought of that. Poor genetic diversity coupled with large numbers (like humans) sometimes indicates an explosive and unsustainable increase in population numbers. Makes me wish that Devils had survived on the mainland. That would have increased the generic diversity.

Maybe breed the devils by looking for genetic diversity ?

Humans have low genetic diversity.

Koala numbers have increased enormously since Europeans arrived, and were rare in the past. The result has been that koalas have low genetic diversity.

Wolves have low generic diversity, very much lower genetic diversity than dogs. Again this could be due to an explosive increase in numbers in prehistoric times.

Cheetah, Hawaiian monk seal and several albatrosses have low genetic diversity. The first two of these have low populations so the situation is not the same.

CrazyNeutrino said:

mollwollfumble said:

Speedy said:

Yes.

I read somewhere that this species’ genetic diversity is poor due to the last ice age. They are on a slow road to extinction regardless of any facial tumour cure.

Poor genetic diversity, I hadn’t thought of that. Poor genetic diversity coupled with large numbers (like humans) sometimes indicates an explosive and unsustainable increase in population numbers. Makes me wish that Devils had survived on the mainland. That would have increased the generic diversity.

Maybe breed the devils by looking for genetic diversity ?

Genetic diversity needs to be there in the first place, which apparently with the devils it is not. The devils do not have any close relative with whom they might breed, so are hampered with gaining additional genes by that means. Then their way of life of basically a scavenger, does not require much adaptation in order to get a feed, so little need for change, unless it is enforced on the animal, like the facial cancer. Even ancient mainland devil populations had a very similar genetic code to the Tasmanian ones or other mainland populations, so even geological separation has had little affect.

The dingo on the mainland was a dramatic change for the devil, but in that instance, it had no defense, nor could it adapt and so went extinct.

mollwollfumble said:

Humans have low genetic diversity.

Koala numbers have increased enormously since Europeans arrived, and were rare in the past. The result has been that koalas have low genetic diversity.

Wolves have low generic diversity, very much lower genetic diversity than dogs. Again this could be due to an explosive increase in numbers in prehistoric times.

Cheetah, Hawaiian monk seal and several albatrosses have low genetic diversity. The first two of these have low populations so the situation is not the same.

I think humans have considerable genetic diversity. There is Neanderthal and Denisovans genes, plus populations differ from each by geological genetic influences and the impact of the diseases of their region, which is why there has been such huge loss of life when highly interacting European populations mix with more stable and isolated native populations.