THRILLING ANATOMY Micro CT scans from different angles show that the innards of the leech newly named for Amy Tan devotes a lot of space to eating (false color gray, digestive tissue) and reproducing (red and various blues show male organs; pink denotes female organs).
M. Tessler et al/Zoologica Scripta 2016
View 3-D reconstruction of leech
At last Science News is able — thanks to novelist Amy Tan — to illuminate a question nagging readers (and often writers) of stories about new species named in honor of celebrities. When someone names a slime-mold beetle or a leech after you and you say you’re honored — really?
Tan (whose novels include The Joy Luck Club and The Valley of Amazement) swiftly supplied a vivid answer to our question about whether “thrilled” was the word to describe her feelings about a January Zoologica Scripta paper naming a small, blood-sucking leech in her honor.
She felt a connection with that particular leech, she writes in an e-mail. Before she knew it would bear her name, she had happened upon the blog written about 10 years ago by researchers looking for leeches, preferably new species, in the rainforests of Australia. “Blood Lust II” was the expedition name used by Mark Siddall, a curator at the American Museum of Natural History and his fellow leech-seekers.
“They described conditions of sweat, mosquitoes, humidity and unwashed clothing,” Tan reminisces. She shared the blog entry for the expedition’s second-to-last day, when the scientists reached an area devastated by Cyclone Larry:
“We're speechless.
There's so little left.
Like a bomb went off.
…Trees, regardless of size, lie twisted and snapped like matchsticks... Worse, the canopy is gone. …Gone. Like a lawnmower came by and simply hacked off the upper layer of the rainforest.
…On the positive side, we're sure we have a new species.”
Tan comments: “That’s how you do science — by mucking about in a vast rainforest with both beautiful and unpleasant conditions, all the while being attuned to the smallest details that make up what we mean by uniqueness.”
The leech, Tan writes, was a “consolation prize,” and she remembered it when she heard years later that the forest-dwelling species would be named Chtonobdella tanae. She knows the explorers and has let one of their lab leeches stroll on her skin (which it did not bite). In the scientific paper officially christening Tan’s namesake, Siddall and his coauthors thank Tan for her support and her companionship on nature explorations and note that her book Saving Fish from Drowning mentions terrestrial leeches three times.
“I spent quite a bit of time reading the paper, and in doing so, I learned a few useful words, like annulate, epididymal, gonopore, and nephridial,” Tan writes. “I already knew the words “seminal” and “receptacle” but until then, I had not had the occasion to use them together during dinner conversations. I have since then.”
Tan went further, out-sciencing by far most news accounts of her namesake leech by actually describing its features (though without using epididymal or nephridial even once).
The first clue to its uniqueness, she notes, were the four rings on each body segment instead of the five normal for the known leeches of the area. It’s a hermaphrodite like other leeches but with some uniquely placed male organs. “I know that its jaw is positioned differently, as are its five pairs of eyes, and that the digestive tract has some neat features as well.” (As paper coauthor Michael Tessler explains, the end of the digestive tract “is twisty and turny and doubles back on itself,” unsurprising for humans, but startling in a leech.)
Tan adds, “I do know that it is not simply the leech that is special in its own right; it is also the way in which it was thoroughly identified.” C. tanae, only a few squishy millimeters wide, would have been a challenge to dissect without distorting internal organs, so the scientists developed ways to prepare a specimen so CT scans highlighted subtleties of its innards. “It's a method that will be used with many specimens, maybe even those from a hundred years ago,” Tan writes.
She signs off by adding, “That's the long answer to: Am I thrilled that this leech bears my name?
“You bet.”
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A 3-D reconstruction of the insides of a Chtonobdella tanae shows some of the leech’s distinctive traits. In the male reproductive tract, one lump (aqua) of epididymal tissue sits in front of the other (blue) instead of side by side as usual. (The red spheres are the multiple pairs of leech version of testes.) Five pairs of green nuggets at one at end of the leech are its eyes, and green squiggles are its unusually squiggly digestive tract. American Museum of Natural History/YouTube |
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