Tasmanian Devils, the real-life marsupial inspiration behind the cartoon beastie, were already an endangered species when nature added insult to injury. In 1996, researchers first formally described Devil Facial Tumor Disease, a cancer that would later turn out to be contagious, passed from devil to devil by biting, mating, and sharing food.
While you're probably familiar with the idea that viruses can cause cancer, that's not what's going on here. Instead, the cancer cells themselves are contagious. It's a rare phenomenon, but not (terrifyingly enough) completely unique. At Nature blogs, Anne-Marie Hodge writes about other cases of contagious cancers in mammals.
One prime example is canine transmissible venereal tumor (CTVT), a histiocytic tumor that is passed between dogs through sex as well as sniffing and licking of the genitals. At one point it was thought that a sexually transmitted virus, similar to HPV, caused this disease. It turns out, however, that it is the CTVT cells themselves that are infectious, not a virus that activates them. The cancerous cells themselves, which are essentially clonal, are what is passed from animal to animal.
For example, when an infected Dog A has genital contact with Dog B, what is transmitted is not some agent (such as a virus) that triggers Dog B's cells to start dividing and creating tumors. Instead it is the cancer cells themselves, which are genetically different from both Dog A and Dog B, which continue to clone themselves on their new victim. Thus it seems animal that receives CTVT from its mate is not so much infected as colonized, and that is why CTVT is sometimes referred to as a "parasitic cancer." The tumors most often appear on the external genitalia, but may also affect the nose and mouth.
There are few interesting aspects of CTVT cells. While normal dog and wolf cells contain 78 chromosomes, the tumor cells have fewer, usually between 57-64, and even those chromosomes bear some distinct morphological differences from those found in healthy dog tissue. The disease also infects coyotes (which also have 78 chromosomes) and red foxes (with only 34 chromosomes).
Image: Wikipedia user Wayne McLean via CC
Via Bora Zivkovic
Can you “hear” motion or light flashes? If so, according to new research from City University London, you may be experiencing a not-so-rare form of synaesthesia. Synesthesia is the fascinating neurological phenomenon whereby stimulation of one sense involuntarily triggers another sensory pathway. For example, a synesthete might taste sounds or hear colors. (In this study, […]
Scientists declared the ruby seadragon a new species in 2015, but that was based on dead specimens in a museum. Now though, Scripps Institution of Oceanography biologist Greg Rouse who led the team that originally discovered the species, managed to find two of the wonderful fish swimming around the Recherche Archipelago, off the south coast […]
Scientific American summarized five of Donald Trump’s “major moves many see as hostile toward science.” They are: • Trump’s pick for head of the U.S. Environmental Protection Agency has actively battled its mission “To lead the EPA, Trump appointed Scott Pruitt, the Oklahoma attorney general who has long opposed environmental regulations and has questioned the science […]
Looking to upgrade your weekend? Here are three randomly awesome products on my mind this week.#3 FRESHeBUDS Pro Magnetic Bluetooth EarbudsAs more and more phones and gadgets switch to Bluetooth-only compatibility, you’ll need to get Bluetooth headphones like the rest of us. I’ve been super impressed with these affordable magnetic headphones. Pull the magnetic earbuds apart to auto-connect […]
Traditional folding wallets are designed for paper bills—but these days, carrying cash is rarely a necessity. More often than not, I don’t carry cash at all. This Bogui Clik Wallet is the best answer I’ve found for avoiding the hassle of those tight-fitting credit card pockets.This attractive, minimalist wallet features a protective lip, so my cards don’t […]
Using my iPhone while it’s charging is always a hassle. With tucked-away outlets and the meager length of included lightning cables, comfortable scrolling while plugged in is annoying. These 10-Ft MFi-Certified Lightning Cables are super convenient and probably the best iPhone accessory purchase I’ve made.At over three times the length of normal cables, these reach anywhere you […]