Tasmanian devils have given rise to a weird new quasi-form of life: a cancer that spreads from animal to animal like a parasite. In tomorrow’s New York Times, I report on the latest analysis of devil’s facial tumour disease, published in this week’s Science. Scientists have now tracked down the cancer to its progenitor: nerve cells known as Schwann cells.

Now scientists can use this evolutionary history to design diagnostic tests for the cancer and perhaps even vaccines. Let’s hope they succeed–the cancer has wiped out 60 percent of all Tasmanian devils since 1996 and has the potential to drive the whole species extinct in a matter of decades.

For more on cancer as a new form of life, check out my earlier blog post on the only other documented case in the wild: a tumor that jumps from dog to dog. (The one major update to that post is that it now looks as if the tumor escaped its original dog host thousands of years ago, instead of hundreds as previously thought.) While dogs and Tasmanian devils are so far the only known hosts to these sorts of cancer, free-ranging tumors may actually be more common than we know right now. They may be particularly likely to arise in small, inbred populations. The similar immune systems of these animals may be easy for the cancer to evade, allowing it to spread quickly. Another hint that infectious cancer isn’t all that rare is the violence with which we reject transplanted organs. Why should our bodies be so well-primed to attack the cells of other humans? One possibility is that invasive cancers have been a long-term threat to the health of our ancestors.

(And for more on cancer as an evolutionary disease, see my article in Scientific American, reprinted in The Best American Science Writing 2008 )

Reference: EP Murchinson et al, “The Tasmanian Devil Transcriptome Reveals Schwann Cell Origins of a Clonally Transmissible Cancer.” Science http://dx.doi.org/10.1126/science.1180616

Image: Wikipedia

[Update 12/31 3 pm: Headline de-apostrophed.]

What’s with all the tongue-eating parasites popping up these days?

At least this one is pretty. (As it should be, given that it’s the winner of the symbiosis-and-parasitism photo contest over at WetPixel.)

A healthy brain, with white matter tracts visualized with diffusion tensor imaging. Source.

In tomorrow’s New York Times, I have an article about the Genomic Encyclopedia of Bacteria and Archaea, a new database that’s designed to span the vast diversity of our planet’s microbes. Check it out!

[Update: one of the scientists behind the encyclopedia, Jonathan Eisen, has blogged about the encyclopedia's history here.]

Image: Flickr

“My name is Steve Kleinedler, supervising editor for the American Heritage Dictionary, where I have worked since 1997. One of my many responsibilities is pronunciation. The tattoo is a stylized version of a phonetic vowel chart — it shows the relative position of the tongue in the mouth when those vowel sounds are articulated. I had a smaller, simpler version done on my upper back in 1993, and I’ve been wanting to get the full version for quite some time.

“The design is by Kyle Nelson of Stoltze Design and the tattoo artist was Mike Helz of Stingray Body Art.”

Click here to go to the full Science Tattoo Emporium.

So the wife and I are ready to investigate our distant past and discover all sorts of unsettling things about our ancestors. Anyone care to recommend any particular genealogical DNA testing outfit? I know of the Genographic Project and a few others, but I don’t know how full or accurate a profile they offer.

How does a scientist study a million genes? In my latest podcast I talk to John Wooley, a leading figure in the new science of metagenomics. Check it out.

Photographer Alex Wild picks his favorite images of insects from the year. Bugilicious.

There comes a time in every science writer’s career when one must write about glass duck vaginas and explosive duck penises.

That time is now.

To err on the side of caution, I am stuffing the rest of this post below the fold. My tale is rich with deep scientific significance, resplendent with surprising insights into how evolution works, far beyond the banalities of “survival of the fittest,” off in a realm of life where sexual selection and sexual conflict work like a pair sculptors drunk on absinthe, transforming biology into forms unimaginable. But this story is also accompanied with video. High-definition, slow-motion duck sex video. And I would imagine that the sight of spiral-shaped penises inflating in less than a third of second might be considered in some quarters to be not exactly safe for work. It’s certainly not appropriate for ducklings.

So, if you’re ready, join me below the fold.

(more…)

Over the past few days, I’ve been following a tale of paleontological woe with a surprisingly happy ending.

Matt Wedel, a paleontologist, has been blogging about his experience with a television show on the Discovery Channel called Clash of the Dinosaurs. It didn’t go well. The producers edited Wedel’s interviews to turn his words around 180 degrees. For example, remember that old notion of big dinosaurs having a second brain along their spinal column? Not true! Wedel explained this, but if you tune into the show, you see Wedel essenitally saying, True!

Wedel understandably flipped out. He complained to the producers and got back a non-apology that just made him angrier. He was transformed into the terrible Blogosaurus, and with his resonant nasal cavity he let out a clarion call for his fellow blogosaurs to stampede the production company

I’ve heard this sort of story many times before, and this is where it usually ends. Blogosaurus slinks back to his office and sulks.

But today the story has another ending. Wedel now reports that someone from the Discovery Channel called him up and is going to make things right. I can only guess that blogs do actually make a difference some of the time. Or maybe just this once.

Still, I find this story heartening, because I find science on television to be so vexing. We’re at the point now where all the pieces are in place for some utterly exhilarating programs. We’ve got awesome computer graphics. We’ve got lightweight HD cameras that people can bring to out-of-the-way places. We’ve got scientists ready to give their time and expertise. We’ve got all sorts of innovative ideas about how to make documentaries. Sometimes they add up into good science shows, but rarely great ones. And too often we end up with Clash of the Dinosaurs, or worse.

There are three kinds of terrible science shows on television.

1. The sleepy, dutiful schlep. Just because a show is accurate doesn’t mean that it’s worth watching.

2. The show that’s crazy from the start. Exhibit A: Nostradamus 2012. Just full-goose bozo from scene one, and spreading misinformation far and wide.

3. The show that could’ve been a contender, instead of a bum, which is what it is. Wedel’s experience is a good example of this category. The show sounded great to Wedel when the producers described it to him. But along the way, somebody got the idea stuck in his or her head that it would be so cool for dinosaurs to have a second brain. It would look great. And so great effort and editing was undertaken to achieve that dream–with no apparent interest in whether it was actually true.

I’ve been involved peripherally in some television science shows. In some cases, the producers and I were totally on the same wavelength. I helped them make their shows accurate and clear, and they understood what I was getting at. In other cases, I got stuck in Category Three situations. I had to explain again and again why something in a script was just totally wrong. I wanted to rig up an electrified fence around the falsehood to keep the producers from sneaking back to it. The producers in these particular cases, I suspect, really do just care about the good look–or, rather, they don’t want to spend the time making the truth look good instead.

Wedel has had a small victory in Category Three. The DVD of Clash of the Dinosaurs will get right what the broadcast version got wrong. Wedel’s experience shows that scientists and audience members can have an effect on science TV. And I suspect that it also shows that deep down, television producers know that they can’t do science shows without scientists. (Although there’s always the chance they’ll turn to pseudo-scientists.)

Still, it would have been nice for the show to have been right from the start–and not just right, but to convey how scientists do science. Some have argued that the only way to be sure you don’t get involved in a turkey is to get lawyerly. Get the final approval on all your material in writing.

It’s good advice, up to a point. At best, it leads to a hostile detente between scientists and producers. If scientists just crouch in their offices, ready to thwack any passing television producer with legal documents, I don’t think we’ll see a blossoming of great science TV any time soon. For that to happen, there will have to be deeper partnerships, in which TV folks recognize what science is actually about, and scientists will leave their staid jargon and lecturing styles at the studio door and spend some serious time thinking about what documentaries can achieve.

In the meantime, as my fossiliferous friend Chris Norris notes, there’s always Wikipedia.

[Image: Sauroposeidon, Matt Wedel's beast of choice, via Wikipedia]

I know that this is Bad Astronomy‘s usual bailiwick, but I had to post this. It’s a glint of sunlight reflecting off the surface of a lake of liquid hydrocarbons on Titan, a moon of Saturn. When I look at it, I wonder what diesel-fueled creatures might be swimming below.  More details here.

How is your brain like a telegraph? Check out my latest column in Discover for the answer.