The Devil Facial Tumour Disease" they suffer from is one of the few non-viral transmittable cancers. According to Wikipedia affected populations after wiped out in just 12-18 months.
It is transmitted by biting, but also any contact with cancer cells (such as sharing food), so the most active/fittest are hit first.
Long term a totally separate population is the only way they will be able to keep the Devils from extinction.
HPV is a virus (human papillomavirus) that can cause cancer, whereas with devil facial tumour disease the cancer itself spreads.
This means the cells that form the devil facial tumour are genetically identical across all individual animals infected with it. Normal cancer cells are your own cells which have developed a genetic abnormality, not somebody else's! As I understand it, an HPV infection increases the chance that one of your own cells will develop a genetic abnormality and become cancerous.
The distinction you are drawing is not relevant to the question or supported by the original claim:
>> The Devil Facial Tumour Disease" they suffer from is one of the few non-viral transmittable cancers.
That phrasing obviously contemplates the existence of viral transmissible cancers such as HPV.
If one person states "this is one of the few known non-viral transmissible cancers", and someone else follows up with the question "are there any transmissible cancers in humans?", how does information on transmissible cancers in humans get judged off-topic? Nobody asked "are there any non-viral transmissible cancers in humans?".
I read "are there any transmissible cancers in humans?" in the context as referring to cancers that are themselves transmissible like devil facial tumor disease. (It appears every result in the first few pages of a Google search for the term "transmissible cancer" refers to transmission of cancer cells themselves, not cancers caused by infectious agents.)
The context explicitly distinguishes "transmissible cancers" from "non-viral transmissible cancers". That's only possible when "transmissible cancers" includes cancers that are transmitted by viruses.
I think it's a lot more than just splitting hairs.
There are many viral-initiated cancers. The virus is transmissible, and then when the virus infects host cells in causes the DNA machinery of the cell to go haywire, leading to cancer. Examples include HPV (causes cervical, anal and throat cancer) and feline leukemia virus (retrovirus which causes weakened immune system and leukemia in cats).
This is very different from a transmissible cancer, where it is the cancer cells themselves that can infect other hosts, which is pretty crazy when you first think about it. According to wikipedia there are only 3 known types among mammals: canine transmissible venereal tumor, devil facial tumor, and another cancer that affects Syrian hamsters.
There's also Human Herpes Virus 8 that causes Kopsi's Sarcoma[0]. Nearly all cases are found in immunocompromised individuals, and in times/places without HAART readily available, it is/was a common cancer in HIV+ people. In these cases, in some sense a co-infection of HHV-8 and HIV causes the cancer.
For pretty much any A and B, you can create a perspective from which A is like B. The interesting question is "in which cases does this perspective give useful insights or solutions?"
For treating a single animal, it's almost certainly useful to view it as a cancer. (Most drugs toxic to it will also be pretty toxic to the host, suppressing angiogenesis is helpful, etc.) From an epidemiology perspective, it probably behaves and spreads most like a bacterial infection. (Simple cell life cycle, limited environmental persistence, etc.) Parasites typically have a much more complex life cycle than these cells, and are much easier to target with drugs that won't harm the host.
So... maybe there's a use case where thinking of it as a parasite is useful, but it's not immediately obvious to me.
Avoiding passing the virus on to female partners isn't the only benefit for men. HPV also can cause penile, throat, and anal cancers in men. For instance, Michael Douglas has stated his throat cancer was caused by HPV acquired through cunnilingus.
I don't believe there's any known human ones, but there's a dog one that is 11,000 years old (Canine Transmissible Veneral Tumour) and there's a clam one.
The dog one is rampant where I live in Mexico. Treatable of catched early and the dog is lucky enough to have someone affluent watching over it, but most don't.
I don’t think there are any known examples of cancer transmission (as opposed to transmission of viruses that cause cancer) in humans; leukemias have shown to be transmissible in mice in the lab.
Due to the high mutation rates of tumor cells, it is unlikely the "same" DNA. And it definitely does not live forever if it wipes out populations. That degree of aggressiveness is not a good survival strategy.
There is a theory that some (now) parasites were actually transmittable cancers before, which then developed multi-cellularity that allowed them to have the distinct cell types that they needed to be an own lifeform. Developing multi-cellularity in eurkaryotes has been reported a few dozen times if I remember correctly. Crazy stuff, if true.
The good news is that it seems unlikely to hop species barriers, or survive long in the absence of Tasmanian Devils. Presumably they’ll be able to reintroduce healthy ones after the cancer wipes them out in a given region.
> Long term a totally separate population is the only way they will be able to keep the Devils from extinction.
Are you sure?
From your Wikipedia link:
> Despite this, devil populations persist in disease-stricken areas.[69] The devils have, in a way, fought back the extinction by developing the gene that is immune to face tumors.
If left to continue to evolve in the wild, I would think that eventually this cancer would eventually be easily classified as its own species... if it can’t be so classified already.
They aren’t dying of anything human introduced... they bite each other’s faces off and it turns into cancer. They really are a fairly horrible creature... like an angry vicious hamster.
I fail to see how this is relevant. Yes, Tasmanian Devil's are dying of "natural causes". But, humans like them and want them to continue living. So, humans will preserve them if possible. Now, natural selection is selecting for creatures that humans like as well as creatures that don't bite each others's faces off. Natural selection does not pick morally good creatures to survive. Natural selection is merely the fact that creatures that live long enough to have babies, live long enough to have babies.
Having lived in a place that had Devils, and having seen them first hand, I'd be so upset if they went extinct. They're such a cute and incredibly iconic animal for us, and the fact they were practically wiped out by a pest animal introduced here for sport-hunting is infuriating and depressing.
I moved to Tasmania to work remotely a few months ago.
I'm yet to see a devil, although I have seen other animals. They did exist on the mainland thousands of years ago but were wiped out by Dingoes. It's assumed these were introduced by Australian Aboriginal people who brought them here from South East Asia.
Tasmania is dingo free, which is why there are still devil's here
I follow https://twitter.com/davidghamilton1 on Twitter who is a Tasmanian Devil researcher and constantly posts fantastic photographs of them (and Quolls and other excellent Australian wildlife).
> Thanks to their sharp teeth devils can slice the meat and crush bones pretty easily. Tasmanian devils have the most powerful bite of any mammal given the size of its body. They can open their jaws 75 – 80 degrees.
> Tasmanian devils have 42 teeth but these are not replaced after birth. They continue to grow all throughout the devil’s life and the growth is gradual. Dogs do replace their teeth.
> They can exert a force of 553 N (56.4 kgf). Thanks to its large head and big jaw-opening, Tasmanian devils can tear apart any meat including the hardest of the bones.
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[ 2.8 ms ] story [ 132 ms ] threadIt is transmitted by biting, but also any contact with cancer cells (such as sharing food), so the most active/fittest are hit first.
Long term a totally separate population is the only way they will be able to keep the Devils from extinction.
https://en.wikipedia.org/wiki/Devil_facial_tumour_disease
https://www.mayoclinic.org/diseases-conditions/hpv-infection...
This means the cells that form the devil facial tumour are genetically identical across all individual animals infected with it. Normal cancer cells are your own cells which have developed a genetic abnormality, not somebody else's! As I understand it, an HPV infection increases the chance that one of your own cells will develop a genetic abnormality and become cancerous.
>> The Devil Facial Tumour Disease" they suffer from is one of the few non-viral transmittable cancers.
That phrasing obviously contemplates the existence of viral transmissible cancers such as HPV.
If one person states "this is one of the few known non-viral transmissible cancers", and someone else follows up with the question "are there any transmissible cancers in humans?", how does information on transmissible cancers in humans get judged off-topic? Nobody asked "are there any non-viral transmissible cancers in humans?".
There are many viral-initiated cancers. The virus is transmissible, and then when the virus infects host cells in causes the DNA machinery of the cell to go haywire, leading to cancer. Examples include HPV (causes cervical, anal and throat cancer) and feline leukemia virus (retrovirus which causes weakened immune system and leukemia in cats).
This is very different from a transmissible cancer, where it is the cancer cells themselves that can infect other hosts, which is pretty crazy when you first think about it. According to wikipedia there are only 3 known types among mammals: canine transmissible venereal tumor, devil facial tumor, and another cancer that affects Syrian hamsters.
[0] https://en.wikipedia.org/wiki/Kaposi%27s_sarcoma
For treating a single animal, it's almost certainly useful to view it as a cancer. (Most drugs toxic to it will also be pretty toxic to the host, suppressing angiogenesis is helpful, etc.) From an epidemiology perspective, it probably behaves and spreads most like a bacterial infection. (Simple cell life cycle, limited environmental persistence, etc.) Parasites typically have a much more complex life cycle than these cells, and are much easier to target with drugs that won't harm the host.
So... maybe there's a use case where thinking of it as a parasite is useful, but it's not immediately obvious to me.
Avoiding passing the virus on to female partners isn't the only benefit for men. HPV also can cause penile, throat, and anal cancers in men. For instance, Michael Douglas has stated his throat cancer was caused by HPV acquired through cunnilingus.
I don’t think there are any known examples of cancer transmission (as opposed to transmission of viruses that cause cancer) in humans; leukemias have shown to be transmissible in mice in the lab.
https://en.wikipedia.org/wiki/Viral_evolution
https://www.nationalgeographic.com/science/article/140716-gi...
https://www.who.int/news-room/fact-sheets/detail/human-papil...
Are you sure?
From your Wikipedia link:
> Despite this, devil populations persist in disease-stricken areas.[69] The devils have, in a way, fought back the extinction by developing the gene that is immune to face tumors.
> ... the descolada, a virus that kills all humans it infects ...
> ... the Descolada is intrinsically tied in with the life cycles of all Lusitanian organisms and may even be sentient itself.
They aren’t dying of anything human introduced... they bite each other’s faces off and it turns into cancer. They really are a fairly horrible creature... like an angry vicious hamster.
All the time?
I fail to see how this is relevant. Yes, Tasmanian Devil's are dying of "natural causes". But, humans like them and want them to continue living. So, humans will preserve them if possible. Now, natural selection is selecting for creatures that humans like as well as creatures that don't bite each others's faces off. Natural selection does not pick morally good creatures to survive. Natural selection is merely the fact that creatures that live long enough to have babies, live long enough to have babies.
I'm yet to see a devil, although I have seen other animals. They did exist on the mainland thousands of years ago but were wiped out by Dingoes. It's assumed these were introduced by Australian Aboriginal people who brought them here from South East Asia.
Tasmania is dingo free, which is why there are still devil's here
You're unlikely to see a Devil in the wild, shy little creatures.
Definitely check out one or all of the wildlife sanctuaries, Trowunna, Bonorong, Devils at Cradle, and others.
I'm in Launceston and operate a laser cutter, if you ever want anythinh metal laser cut hit me up, contact details in my profile.
Here's a recent picture of their teeth: https://twitter.com/davidghamilton1/status/13927908758691266...
> Tasmanian devils have 42 teeth but these are not replaced after birth. They continue to grow all throughout the devil’s life and the growth is gradual. Dogs do replace their teeth.
> They can exert a force of 553 N (56.4 kgf). Thanks to its large head and big jaw-opening, Tasmanian devils can tear apart any meat including the hardest of the bones.
https://tasmaniandevil.net/tasmanian-devil-teeth/
the video in this link has more tidbits and is cute as hell.
[1]: https://www.nationalgeographic.com/science/article/who-are-y...