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Tasmanian Devils and Devil Facial Tumor Disease (DFTD)

Linda Crampton is a writer and experienced science teacher with an honors degree in biology. She enjoys writing about science and nature.

The Sad Case of an Endangered Marsupial

The Tasmanian devil is the largest carnivorous marsupial in the world. It’s known for its loud screams, shrieks, and snarls. Sadly, it’s an endangered animal. A major reason for this population status is a form of cancer that produces tumors on the animal's face. The disorder is known as devil facial tumor disease, or DFTD. The cancer is contagious and is transmitted when one animal bites another’s face, as may happen during mating and feeding. The disease is often fatal.

Researchers have discovered that immunotherapy helps Tasmanian devils by either preventing tumor development or causing existing tumors to regress. More research and trials are needed, but immunotherapy might eventually be a helpful treatment or prevention strategy for devil facial tumor disease. In addition, some hopeful signs have recently appeared in the wild population of the animal. The disease is still a major concern, however.

An Introduction to the Animal

Tasmanian devils generally don't attack people. Like most wild animals, though, they would probably do so in self defence and could inflict a nasty injury.

Facts About the Tasmanian Devil

The Tasmanian devil has the scientific name Sarcophilus harrisii. It lives only in Tasmania. The animal has a stocky build and is about the size of a small dog. It’s about 0.3 meters or twelve inches high at the shoulder when fully grown and about 0.6 meters or two feet long. Adult males weigh around fourteen kilograms or thirty pounds and adult females a little less.

The devil is mostly black in color but often has a white patch on its chest and side or on its rump. It may also have patches of brown hair. The animal has a big head, powerful jaws, and a large nose. Its ears are often noticeably pink or red on their inner surface. They may turn an even deeper shade of red when the animal is upset.

The devil has a reputation as a fierce creature with respect to its behavior towards other members of its species. Its growls, barks, and screams while feeding support this reputation. The sounds may be bone-chilling for humans. A loud and threatening sneeze is also part of the animal's repertoire and is used to establish dominance.

The devil's behavior is sometimes misunderstood. Some of the sounds that it produces prevent a fight with other animals instead of triggering one. Parks and Wildlife Service Tasmania says that most bites are linked to reproduction and that bites during feeding are rare.

Tasmanian devils vary enormously in personality. Some individuals are very calm and tolerant, others very excitable.

— Parks and Wildlife Service Tasmania

The Save the Tasmanian Devil Program

The Tasmanian devil is often referred to as simply a "devil". It's affectionately known as a Tassie devil. (Yes, some people do look upon the animal with affection.)

Daily Life of the Animal

Tasmanian devils live in a wide variety of habitats. They seem to enjoy water and are good swimmers. They are usually nocturnal. During the day, they hide in places such as burrows, thick bush, hollow logs, and caves. A large rock or stone may also provide suitable shelter. The animals may leave their shelter during the day to sunbathe, though they try not to attract attention while they do this. During the night, the devils search for food. They may travel ten to twenty kilometers (six to twelve miles) in a night. They have a home range but don't maintain a territory. They are solitary animals but sometimes meet other devils while feeding.

The animals are mainly scavengers but also hunt prey, including frogs, lizards, ground birds, small mammals, and insects. Their sense of smell is excellent and very helpful in the hunt for food. They produce a strong and unpleasant smell themselves when they are stressed. They also have good hearing. The strong jaws and teeth of the devils enable them to eat the entire body of many animals, including the bones. When they are well fed, fat is deposited in their tail. The animals play a useful role in their environment because they remove the carrion that attracts insects.

An animal at the Tasmanian Devil Conservation Park

An animal at the Tasmanian Devil Conservation Park

An open mouth display is often not what it seems. The animal above is likely displaying uncertainty or fear instead of aggression.

Reproduction Facts

The Tasmanian devil is a marsupial, which means the babies are born in a very immature stage and develop in the mother’s pouch. The gestation period is around three weeks. The babies are called imps or joeys. When the imps are born, they are as small as a grain of rice. They are pink in color and have no hair. They have to crawl over their mother's body to reach the pouch, whose opening faces backwards. Up to fifty imps enter the pouch, but only four teats are available. An imp grabs hold of a teat with its mouth and stays attached to it as it grows. The imps that don't reach a teat die.

The successful youngsters stay in the pouch for about four months as they complete their development. When they emerge, their mother often carries them around on her back until they get too big for this form of transport. The devils can climb trees while they are small. This task is difficult for the adults, however. The youngsters become independent from their mother around five months after leaving the pouch.

The animals are reproductively mature at around two years of age. Their normal lifespan appears to be five to eight years. Wild devils generally live for a much shorter time than this at the moment due to devil facial tumor disease.

Although the wild devil population is in serious trouble, captive and healthy animals exist in various facilities. Breeding programs have been established in some places.

Moments in a Tasmanian Devil's Life

Devil Facial Tumor Disease

Devil Facial Tumor Disease was discovered in 1996. An affected animal develops large, irregularly shared lumps on its face and head. Lumps may partially or completely cover an eye and may also appear inside the mouth. Animals with the disease generally live for only six to twelve months once the tumors appear. They often die due to starvation because the tumors around their mouth prevent them from eating.

The disease is transmitted by living cancer cells being passed from one animal to another. When cells from another individual's body enter a recipient, the recipient's immune system normally recognizes that an invader is present and attacks the cells. For some reason, this doesn't happen in DFTD. The devil's immune system remains quiescent and the cancer cells are able to multiply.

No treatment or effective vaccine for DFTD exists at the moment. Researchers are studying the disease in an attempt to help Tasmanian devils. Some interesting discoveries have been made, but more research is necessary.

MHC Molecules

Researchers think the devil's immune system isn't activated because the cancer cells don't produce MHC molecules. "MHC" stands for major histocompatibilty complex. MHC Class 1 molecules are glycoproteins (proteins with carbohydrate attached) found on the surface membranes of cells with a nucleus. The molecules help the immune system to distinguish self from nonself. MHC molecules are involved in the fight against pathogens and in the rejection of a tissue transplant from a genetically-different individual.

Function of MHC Molecules

MHC molecules display a small piece of protein known as a peptide, which is obtained from inside the cell. This peptide may be a normal component of the cell or it may be abnormal, such as a peptide obtained from a virus or bacterium that has infected the cell. Certain T cells in the immune system have already been primed to recognize problematic peptides that have entered the body. An appropriate T cell "finds" a dangerous peptide on an MHC molecule by binding to it. Another type of T cell then destroys the cell displaying the peptide.

An Allograft

Transmission of DFTD cells from one devil to another is a type of allograft (a tissue transplant from one member of a species to another member who is genetically different). We would expect the recipient's body to recognize that the tissue doesn't belong in the body because the MHC molecules on its cells display the wrong peptides. Since the devil cancer cells have no MHC molecules on their surface, however, there is nothing for the T cells to bind to and they don't recognize that the tissue is harmful.

The devil's immune system does recognize allogeneic skin grafts (those in which the donated skin cells are genetically dissimilar to the recipient’s) and at least some types of cancer cells originating outside their body. There seems to be a specific problem with DFTD cells that prevents the animal's immune system from attacking them.

Researchers have found that DFTD cells contain the genes needed to make MHC molecules, but the genes are inactive. Activating the genes in the cancer cells might be helpful in preventing or treating the disease.


Immunotherapy is the modification of the immune system's action in order to treat a disease. The immune system may be enhanced in some way or it may be inhibited. In 2017, a team consisting of multiple researchers reported the use of immunotherapy in Tasmanian devils. Due to the endangered status of the population, the researchers couldn’t use many animals in their project. The results of the experiment could be significant, however.

The research involved nine healthy animals, some of which were at an "advanced" age. This may have affected the results of the experiment. The experiment lasted for five years. The immunization consisted of the administration of modified DFTD cells that had been triggered to develop MHC molecules. Encouraging effects of the immunotherapy appeared in some of the animals.

  • One of the immunized animals didn't develop tumors after exposure to unmodified DFTD cells.
  • Six of the animals developed tumors when exposed to unmodified DFTD cells before immunization. When they were later immunized by modified DFTD cells, the tumors regressed in three of the animals. The regression was accompanied by the formation of antibodies to the cancer cells.

Two animals in the experiment were never immunized. One was given an adjuvant (a substance that was used to boost immunity) while the other received no special treatment. These animals were used as controls. Controls are used in experiments in order to prove that a factor that is being tested—in this case, modified cancer cells—is the cause of any benefit that is observed.

An animal in the Australian Reptile Park

An animal in the Australian Reptile Park

Potential Problems With the Experiment

Though the results of the immunotherapy experiment are intriguing, the sample size was small and the age of some of the animals wasn't ideal. The animals were aged five to seven at their entry into the experiment, which meant that at least some were near the end of their natural lifespan. The fact that there was some success as a result of the experiment is a hopeful sign, though.

One issue that might be a problem for some people is that healthy animals were exposed to the devil facial tumor disease during the experiment. A discussion about the ethics and value of deliberately producing a disease in a healthy animal would be a long one. I think it's an important topic to consider, however.

Efforts to manage the devils, such as the development of an immunotherapy, are ongoing, but remain in a research-and-development phase.

— David Pemberton, Save the Tasmanian Devil Program

Hopeful Signs for the Population

Although the Tasmanian devil situation is serious, a few hopeful signs have appeared. In certain areas, the number of devils is currently not as bad as might have been expected due to an interesting phenomenon. The animals in the area are rarely living beyond the age of two due to the disease. The age of reproduction has decreased, however. Now females as young as one are having babies, which replace the older animals who have died.

Another hopeful sign is that some animals have developed genetic changes that are helping them to fight the cancer. Some Tasmanian devils are surviving for longer than expected with the tumors. In some individuals, the tumors have regressed and even disappeared without intervention from humans.

In 2018, researchers said that the population had decreased by around 70% overall since DFTD first appeared and by around 90% in some areas. At that time, scientists said that the species may be extinct in the wild in twenty to thirty years unless it's helped.

On the other hand, in 2019 some researchers were optimistic due to the hopeful signs that have appeared, and in 2020 further discoveries increased the optimism. In late 2020, some more encouraging signs appeared. Researchers say that the rate of disease spread has decreased significantly. This may be due to the fact that the density of the overall population has decreased as sick animals have died. It’s also possible that the behavior of the remaining animals has changed in a way that reduces the spread of disease or that their immune systems have found a way to fight the infection.

Tasmanian Devil Joeys

Until recently it (DFTD) was spreading exponentially, like the pandemic coronavirus among humans in many parts of the world. But geneticists calculate that each infected devil now transmits tumor cells to just one—or fewer—other devils. That could mean the disease may disappear over time.

— Elizabeth Pennisi, Science Magazine (American Association for the Advancement of Science)

An Uncertain Future With Encouraging Signs

The fact that healthy Tasmanian devils are present and reproducing in captivity gives us a safety net for the species. It also allows people to see the animals up close, which may promote public concern. Life in captivity isn't ideal for the animal, but captive animals are creating a population that could be released into the wild. The strategy won't be helpful if the released animals develop cancer, however. Some researchers worry that if the density of the wild population increases due to the addition of formerly captive animals, the incidence of disease may increase as well.

A 2021 report concluded that although the situation is serious, there are still signs of hope. The animal's population has been greatly reduced since the start of the outbreak, but at least some of the remaining individuals seem to be successfully dealing with the disease. Scientists are investigating ways to help the population do this.

Tasmanian devils have to survive road traffic and habitat loss. For small devils, predation by eagles or owls or by a quoll (another type of carnivorous marsupial) is a danger. Surviving devil facial tumor disease is the biggest problem for the animals, however. Nature and science may be needed to save them. The Tasmanian devil may be a strange animal by human standards, but I think it's worth saving this unique member of the animal kingdom.


  • Tasmanian devil facts from the San Diego Zoo
  • Information about Tasmanian devils from the Save the Tasmanian Devil website (which is run by the Tasmanian government)
  • The major histocompatibility complex from Garland Science and the National Institutes of Health (NIH)
  • Cell-mediated immunity from John W. Kimball (a retired Biology professor and textbook creator)
  • Regression of devil facial tumour disease following immunotherapy in immunised Tasmanian devils from the Nature Journal's Scientific Reports
  • DFTD information from the Transmissible Cancer group at the University of Cambridge
  • Tasmanian devil populations continue to decline: Devil facial tumor disease poses ongoing risk for wild populations from the news service
  • Possibly helpful changes in the marsupial's population from the CBC (Canadian Broadcasting Corporation)
  • Tasmanian devils claw their way back from extinction from AAAS Science
  • Evolution of the animals may be helping their situation from TheScientist website
  • 2021 news about the species from the University of Tasmania

© 2018 Linda Crampton


Linda Crampton (author) from British Columbia, Canada on April 28, 2018:

Thanks, Peggy. The current plight of the Tasmanian devil is sad. I hope the species can be saved. There is an ethical dilemma in many types of research involving animals. I'm glad that some progress is being made in dealing with the situation, but it's still a serious problem.

Peggy Woods from Houston, Texas on April 28, 2018:

What an interesting article Linda! That National Geographic video near the top of your page was most informative. It is sad that a form of cancer that as yet has no cure may be the cause of this animal becoming extinct. Let us hope that does not happen and that more research will be able to solve that problem. As to infecting healthy animals in order to do the research...that will always be an ethical dilemma.

Linda Crampton (author) from British Columbia, Canada on April 20, 2018:

Thank you very much.

I AM DOING RESEARCHES on April 20, 2018:

This is well written. Good job!

Linda Crampton (author) from British Columbia, Canada on April 06, 2018:

The International Union for Conservation of Nature says that the animals can be found throughout Tasmania. They are also found on Robbins Island off the northwest coast of Tasmania.

Linda Crampton (author) from British Columbia, Canada on February 19, 2018:

Hi, Natalie. It's interesting to hear that watching Taz caused you to investigate real Tasmanian devils. Like you, I hope immunotherapy proves to be an effective treatment for the animals.

Natalie Frank from Chicago, IL on February 19, 2018:

I have been interested in Tasmanian Devils ever since I watched Sat. morning cartoons as a kid. I know there has been criticism of the way they are portrayed, but I think kids have always found something endearing about Taz, and seeing it made me look up and learn about real Tasmanian Devils. It is sad that they are endangered especially since the disease is transmitted through what seems to be a normal mating behavior. Hopefully the immunotherapy will prove to be an effective treatment. Thanks for the article.

Linda Crampton (author) from British Columbia, Canada on February 18, 2018:

Thank you very much for sharing your thoughts and the interesting information, Suhail. I have a similar point of view to you. Biologically, we are animals. We have the most advanced brain of any creature on the planet, but we are related to other animals. I think this is an important point for people to consider.

Suhail Zubaid aka Clark Kent from Mississauga, ON on February 18, 2018:

Hi Linda,

I love Tasmanian Devils, have watched several TV documentaries on them (more than any other animal except gray wolves, and elephants), and this article has both been an interesting and a saddening read.

The religion I come from has been incorrectly associated with violence, but it isn't so. I was taught from the beginning that Humans are 'God's noblest of creations', but that all other animals have souls, that they have communities like humans, that we, humans, have a duty to them, and that no human will enter heavens if an animal suffered at his/her hands.

Scientifically speaking, presence of wild animals is indicative of healthy ecosystem that also supports homo sapiens.

Psychologically speaking, caring for animals comes from caring for humans. Both go hand in hand. Presence of animals and wildlife brings solace in the lives of many people.

Economically speaking, wildlife is a good source of tourism that helps support and develop local economies.

All I wanted to say is trying to save Tasmanian devils or any other animal that is at the verge of extinction makes good sense.


Suhail and my dog K2

Linda Crampton (author) from British Columbia, Canada on February 17, 2018:

Thank you for sharing your thoughts, Val. They are always interesting.

ValKaras on February 17, 2018:

Linda--I respect your arguments coming from your love of animal kingdom and your deeper understanding of their role on this planet than my mindset can even begin to appreciate.

While evolutionists might talk about "survival of the fittest"---which even includes the concept of an extinction---I prefer yapping about a "survival of the most conscious", which places homo sapiens in the top ranks of that race.

I am even going a bit further in my own modest speculations in all these matters---as I envision those among us humans with a more evolved consciousness running a better chance of surviving the increasing challenges of stressful, polluted, and disharmonious world.

Level of achieved consciousness is in reverse proportion to the level of our animalistic mental survivalism characterized by greed, fear, arrogance, territoriality, and other pearls of inhuman functioning.

Thus, regardless of the sentiment we may harbor about animals, those edible and cute or those wild and ugly, the phenomenon of man on this planet somewhat changes the rules of the biological game. His essence of a spiritual, conscious, non-animal being changes everything.

It has been proven time and time again that we can heal ourselves by the mere use of our minds, and I have my personal proofs of that. The course of progress on this planet is not about dragging behind us our animalistic roots but to separate ourselves from them.

As for the medicines derived from animals, as we get more conscious we will be healthier and healthier, and in theory, we don't even need doctors at all, because our bodies are made to maintain, repair, and rejuvenate themselves on their own. Doctors are only boosting up those mechanisms in us, not doing any healing anyway.

So, again, in my worldview as much as it includes animals, I don't see a point of wasting money and time on teaching a chimp to act like a man---but doing our best to find ways to stop man from acting like a chimp.

However, all this is not to make your views "wrong" my friend---we are not playing that game of "right-wrong", we are just expressing our intellectual preferences, and I will always respect yours.

Linda Crampton (author) from British Columbia, Canada on February 17, 2018:

Thanks for sharing your opinion, Val. I have a different opinion from you, as I’m sure you guessed, but I still appreciate your comment!

One concern I have about deciding that the Tasmanian devil doesn't matter is the thought of where we draw the line about the right of an animal to survive and the need to help them. Do we say yes to the animals that we currently keep as pets or livestock or that make a useful product for us but no to similar animals that haven’t been domesticated or who aren’t eaten? Do we say yes to animals who appeal to some people because of their cuteness but no to those who are ugly by some people’s standards? Do we say yes to a gorilla because it shares ninety-eight percent of our DNA but no to a lemur, which is also a primate like the gorilla and us but shares fewer of our genes? Is there a percentage of gene similarity to us that makes an animal worth saving?

The loss of animals could be a problem for us. Animals can give us new medicines, such as an important drug for nerve pain discovered in cone snails and medications based on components of snake venom, or they can help us to understand a process in our body better. They can also remove pests or carrion that attract pathogens or insects that affect our lives, as the Tasmanian devil does. They can provide food for other animals that many people consider to be valuable.

Yes, an argument can be made for destroying pests that harm us. The allocation of funds for saving an animal species or the safety of visiting their habitat to help them can also be a problem. When saving an animal is possible, however, I think it should be attempted.

ValKaras on February 17, 2018:

Linda---I probably deserve to be stoned by naturalists of the world, but my instincts are telling me that we don't need most of the species.

If we think of the food chain in nature providing an excuse for their existence, let those religiously inclined folks think a little---if god created lions to prevent overpopulation of water buffalos, why did he bother creating water buffalos in the first place.

O.K., I am a comedian too.

So, when I hear how this or that species are at a verge of their extinction, my heart is not bleeding for them. As far as I care, we don't really need any crocs and poisoning snakes and sharks, to mention just these few. O.K. we don't need politicians either, and they will probably be the last to be extinct on this planet.

Sorry, Linda, I know how much you care for animals, even these ugly Tasmanian Devils, but we should also make extinct lions and monkeys and poisonous snakes from our own, human nature---not to mention "devils" in some of us; so, as far as I care, whatever happens-happens to the Tasmanian one.

Linda Crampton (author) from British Columbia, Canada on February 16, 2018:

Thank you very much for the comment, Peg. I think the joeys are cute. Even the adults hold some attractions for me. They are interesting animals. I hope they survive for their sake and for ours.

Peg Cole from North Dallas, Texas on February 16, 2018:

You pick the most interesting topics and this is no exception. I loved learning about the little Tasmanian Devil and its offspring. Sad to learn that they are facing such a difficult disease and hoping that research will lead to a cure that might also help other species like humans. Wonderful video on the joeys. :)

Linda Crampton (author) from British Columbia, Canada on February 16, 2018:

Hi, Heidi. I thought of the Looney Tunes character as well but thought I shouldn't mention it in a science article! The fact that Tasmanian devils and humans are both mammals means that discoveries in the devils may help us. I hope that's the case.

I hope you have a happy weekend as well, Heidi.

Heidi Thorne from Chicago Area on February 16, 2018:

I thought of Looney Tunes depiction of the fierce and wild Tasmanian Devil when I saw the title. :) The real thing, of course, doesn't live up to that reputation.

Definitely a species that needs our help! I hope they can find a solution to this cancer. In doing so, I wonder what researchers will discover about some of the tough cancers that humans are battling, too.

Thanks for again sharing your knowledge of the natural world with us! Happy Weekend!

Linda Crampton (author) from British Columbia, Canada on February 16, 2018:

Hi, Bill. No, the animal generally isn't cuddly—though I have seen some videos in which it appears to be—but as you say, any endangered animal is a friend of mine!

Linda Crampton (author) from British Columbia, Canada on February 16, 2018:

Hi, Devika. It's wonderful when we're able to save an endangered animal. I hope we can save the Tasmanian devil.

Linda Crampton (author) from British Columbia, Canada on February 16, 2018:

Hi, Mary. Yes, I think the knowledge gained by studying how Tasmanian devils respond to intruding cells may be helpful for us. We may learn something applicable to human biology. Thank you for the comment.

Bill Holland from Olympia, WA on February 16, 2018:

Not what I would call a cuddly animal, but any animal endangered is a friend of mine. Thank you for raising awareness.

Devika Primić from Dubrovnik, Croatia on February 16, 2018:

It is such a miracle to save animals. You shared another informative and interesting hub. Lots to think about here on such researches.

Mary Norton from Ontario, Canada on February 16, 2018:

I have heard of these devils but have never seen one. I may not approve of some experimentation on animals but its contribution to Science and medicine is immense. In this case, we are trying to save these animals but the knowledge this will bring will also help us.

Linda Crampton (author) from British Columbia, Canada on February 15, 2018:

Hi, Flourish. I hope we can save the animals from extinction, too. The thought of them dying from such a horrible disease is very sad. Thanks for the comment.

FlourishAnyway from USA on February 15, 2018:

I enjoyed this very much and the videos help create an endearing picture of this endangered animal. In a way they are cute and I really do hate to see animals suffer, particularly starving to death. I’d like to think we can save them from extinction.

Linda Crampton (author) from British Columbia, Canada on February 15, 2018:

Thank you, Jackie. I always appreciate your kind comments!

Jackie Lynnley from the beautiful south on February 15, 2018:

Might be one of my least favorite things but still I believe all are here for a reason and therefore should remain. Very interesting that they carry their young like a kangaroo and as always so informative, interesting and well done, Linda.