September 12, 2019
(++++) ANGELS AND DEVILS
Saving the Tasmanian Devil: How Science Is Helping the World’s Largest Marsupial Carnivore Survive. By Dorothy Hinshaw Patent. Houghton Mifflin Harcourt. $18.99.
Tasmanian devils – the real ones, not the hilariously giant-mouthed version in Bugs Bunny cartoons – are not really devilish creatures, although their eerie-sounding screams and shrieks, heard at night by the first English settlers of Tasmania in the early 1800s, certainly seem devilish enough and are responsible for the creature’s common name. Scientifically known as Sarcophilus harrisii, the Tasmanian devil is about the size of a small dog – a bit more or less than 15 pounds – and has been the largest marsupial carnivore in the world since 1936, when the even larger thylacine (sometimes called the Tasmanian tiger or Tasmanian wolf, although it was neither tiger nor wolf) became extinct. And extinction seemed to be on the near horizon for Tasmanian devils as well just a few years ago, when a horrific condition known as devil facial tumor disease (DFTD) swept through the population like wildfire.
DFTD is a cancer, and most people believe that cancers are not contagious. In truth, most cancers are not: DFTD is one of the very few known exceptions. It is transmitted by face-to-face biting, which happens to be a big part of Tasmanian devils’ existence, both in play and in serious combat (often related to mating season). DFTD requires an open facial wound to spread to a new subject – and devils nearly always have minor wounds in their mouths, because they scavenge on sharp bones. They are a perfect host for DFTD – so perfect that the disease, discovered in the mid-1990s, was considered capable of destroying the entire population of wild Tasmanian devils within 20 years. They could all have been gone by now.
That has not happened, and Saving the Tasmanian Devil is an excellent explanation, for young readers, of why not. Dorothy Hinshaw Patent, who is no scientist but is a prolific author of books for young people (she has written more than 100), connected with a college friend whom she had not seen for 50 years and who had become a geneticist specializing in Australian animals – and that led Patent to visit her friend, Jenny Marshall Graves, in Tasmania, and get the story of Tasmanian devils and DFTD in a form that a non-scientist such as Patent could easily understand and could then communicate to readers.
The coincidence of the Patent-Graves connection and the excellence of Saving the Tasmanian Devil show that angels seem to be watching over these devils in their struggle for species survival. More prosaically, those angels are the scientists who have made significant headway against DFTD, and while the devils themselves are merely trying to get on with their lives, the scientists are attempting, so far with some success, to keep the species going. Like other books in the always excellent “Scientists in the Field” series, Saving the Tasmanian Devil does an exceptional job of showing how science is done on a day-to-day basis, not as glamorized by films and TV programs. It is full of drudgery and daily challenges, and a lot of it is frustrating – in the case of DFTD, because finding a way to stop the spread of the disease was a race against time, and one that researchers appeared likely to lose. Patent’s book focuses not only on Graves but also on other scientists involved in the fight for the devils: ecologist Menna Jones, cancer researcher Greg Woods, and a graduate student in genomics named Alex Fraik. The book not only shows their work but also explains, with considerable clarity, what cancer (in general) is and what DFTD (in particular) does. The many photos, from the scientists themselves and a number of other sources, shed light on devils’ everyday existence and on how scientists are working to save them. The single picture of a devil with DFTD is genuinely frightening, showing just how awful the disease looks and making the battle against it seem all the more urgent.
There are sanctuaries for Tasmanian devils – Patent visits one – and for a time, it seemed likely that devils would become extinct in the wild and would have to be repopulated (hopefully) by captive populations. Now that has become more of a backstop plan than a genuine expectation, as scientists continue to make progress against DFTD. Sanctuary-kept devils have issues of their own: as Patent explains and shows, devils, which by their nature forage over a considerable distance, have something of a nervous breakdown when confined to small spaces – one of them is seen obsessively “running, running, running around and around, only stopping to sleep, eat, or drink.” So the angelic impulses of scientists have their own downsides. But those pale beside the ravages of DFTD, which spreads because devils’ “immune cells don’t recognize the cancer cells as ‘other,’ so these cells just keep dividing and dividing until they kill the host.” The answer to fighting DFTD appears to lie in awakening and modifying the devils’ immune system through genetic modification using an immunization technique akin to vaccination. An actual vaccine does not exist, but the gene-modification approach is already in use, with immunized devils released back into the wild and now being observed to test the efficacy of the approach. All this and more is to be found in Saving the Tasmanian Devil, a book that is as full of fascination as it is of initial despair, more-recent hope, and the reality – which young readers will understand clearly – that the fight for the devils is by no means over and by no means assured of eventual success.