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Karl Ragnar Gjertsen via Wikimedia Commons // CC BY 2.5
Karl Ragnar Gjertsen via Wikimedia Commons // CC BY 2.5

10 Juicy Facts About Leeches

Karl Ragnar Gjertsen via Wikimedia Commons // CC BY 2.5
Karl Ragnar Gjertsen via Wikimedia Commons // CC BY 2.5

Leeches get a bad rap, but they’re actually pretty cool once you get to know them. Parasite expert, curator at the American Museum of Natural History, and self-described Leech Guy Mark Siddall shared some surprising facts about the worms we love to hate. 

1. THEY DON’T ALL SUCK BLOOD.

Hematophagous, or blood-feeding, species are only one type of leech. “The vast majority of species are [hematophagous],” Siddall tells mental_floss, “but it depends on the environment. In North America, there are probably more freshwater leeches that don’t feed on blood than there are blood-feeders.” And even among the hematophagous species, there are not too many who are after you. “Very few of them are interested in feeding on human blood,” Siddall says. “Certainly they’ll do it, if they’re given the opportunity, but they’re not what they’re spending most of their time feeding on.” 

2. THEY’RE EVERYWHERE.

Image Credit: Pieria via Wikimedia Commons // Public Domain

“Every continent on the planet has leeches, with the exception of Antarctica,” Siddall says. “And even then there are marine leeches in Antarctic waters.” Humans have co-existed with leeches for so long, according to Siddall, that just about every language has a word for leech. 

3. THEY’VE MADE A COMEBACK IN MEDICINE.

Image Credit: Triin Erg via Wikimedia Commons // CC BY 2.5

Bloodletting for bloodletting’s sake has fallen out of favor with Western physicians, but that doesn’t mean medicinal leeches are enjoying a cushy retirement. Today, surgeons keep them on hand in the operating room and use them as mini-vacuums to clean up blood. “That is a perfectly sensible use of leeches,” Siddall says. Other uses, though, are less sensible: “The more naturopathic application of leeches in order to get rid of bad blood or to cure, I don’t know, whatever happens to ail you, is complete hooey,” he says. How on earth would leeches take away bad blood and leave good blood? It’s silly.” 

4. NOVELIST AMY TAN HAS HER OWN SPECIES.

Land-based leeches made an appearance in Tan’s 2005 book Saving Fish from Drowning, a fact that instantly put the author in leech researchers’ good graces. “There are not a lot of novels out there with terrestrial leeches in them,” Siddall says. So when he and his colleagues identified a new species of tiny terrestrial leeches, they gave the leech Tan’s name. The author loved it. “I am thrilled to be immortalized as Chtonobdella tanae,” Tan said in a press statement. “I am now planning my trip to Queensland, Australia, where I hope to take leisurely walks through the jungle, accompanied by a dozen or so of my namesake feeding on my ankles.”

5. THEY CAN GET PRETTY BIG.

The giant Amazon leech (Haementeria ghilianii) can grow up to 18 inches and live up to 20 years. And yes, this one’s a blood-feeder. Like all hematophagous species, H. ghilianii sticks its proboscis (which can be up to 6 inches long) into a host, drinks its fill, and falls off. Scientists thought the species was extinct until a zoologist found two specimens in the 1970s, one of whom he named Grandma Moses. We are not making this up.

6. THEY MAKE GOOD BAIT.

Many walleye anglers swear by leeches. “A leech on any presentation moves more than other types of live bait," pro fisher Jerry Hein told Fishing League Worldwide. "I grew up fishing them, and I think they're the most effective live bait around no matter where you go." There’s an entire leech industry to provide fishers with their bait. One year, weather conditions kept the leeches from showing up in their typical habitats, which prevented their collection and sale. Speaking to CBS news, one tackle shop owner called the absence of leeches “the worst nightmare in the bait industry.”

7. THEIR SEX IS MESMERIZING.

Like many worms, leeches are all hermaphroditic. The specifics of mating vary by species, but most twine themselves together and trade sperm packets. (The two leeches in the video above are both named Norbert. We’re not totally sure why Bono is involved. The world is a mysterious place.)

8. SOME SPECIES MAKE SURPRISINGLY CARING PARENTS.

“There’s a whole family of leeches that, when they lay their eggs, will cover them with their own bodies,” Siddall says. “They’ll lay the eggs, cover them with their bodies, and fan the eggs to prevent fungus or bacteria from getting on them, and then when the eggs hatch, they will attach to the parent. They’re not feeding on the parent, just hanging on, and then when the parent leech goes to its next blood meal it’s carrying its offspring to its next blood meal. That’s pretty profound parental care, especially for invertebrates.”

9. LEECH SCIENTISTS USE THEMSELVES AS BAIT.

Siddall and his colleagues collect and study wild leeches. That means hours of trekking through leech territory, looking for specimens. “Whether we’re wandering in water or traipsing through a bamboo forest,” Siddall says, “we are relying on the fact that leeches are attracted to us.” Do the leeches feed on them? “Oh my god, yes,” Siddall says. “We try to get them before they feed on us … but sometimes, obviously, you can’t help it.”

10. YOU MIGHT BE THE NEXT TO DISCOVER A NEW SPECIES.

Despite living side-by-side with leeches for thousands of years, we’ve still got a lot to learn about them. Scientists are aware of about 700 different species, but they know there are many more out there. “I’ll tell you what I wish for,” Siddall says. “If you ever get fed on by a leech, rather than tearing off and burning it and throwing it in the trash, maybe observe it and see if you can see any color patterns. Understand that there’s a real possibility that it could be a new species. So watch them, let them finish. They’re not gonna take much blood. And who knows? It could be scientifically useful.”

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Courtesy of The National Aviary
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Animals
Watch This Live Stream to See Two Rare Penguin Chicks Hatch From Their Eggs
Courtesy of The National Aviary
Courtesy of The National Aviary

Bringing an African penguin chick into the world is an involved process, with both penguin parents taking turns incubating the egg. Now, over a month since they were laid, two penguin eggs at the National Aviary in Pittsburgh, Pennsylvania are ready to hatch. As Gizmodo reports, the baby birds will make their grand debut live for the world to see on the zoo's website.

The live stream follows couple Sidney and Bette in their nest, waiting for their young to emerge. The first egg was laid November 7 and is expected to hatch between December 14 and 18. The second, laid November 11, should hatch between December 18 and 22.

"We are thrilled to give the public this inside view of the arrival of these rare chicks," National Aviary executive director Cheryl Tracy said in a statement. "This is an important opportunity to raise awareness of a critically endangered species that is in rapid decline in the wild, and to learn about the work that the National Aviary is doing to care for and propagate African penguins."

African penguins are endangered, with less than 25,000 pairs left in the wild today. The National Aviary, the only independent indoor nonprofit aviary in the U.S., works to conserve threatened populations and raise awareness of them with bird breeding programs and educational campaigns.

After Sidney and Bette's new chicks are born, they will care for them in the nest for their first three weeks of life. The two penguins are parenting pros at this point: The monogamous couple has already hatched and raised three sets of chicks together.

[h/t Gizmodo]

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holidays
Bleat Along to Classic Holiday Tunes With This Goat Christmas Album
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iStock

Feeling a little Grinchy this month? The Sweden branch of ActionAid, an international charity dedicated to fighting global poverty, wants to goat—errr ... goad—you into the Christmas spirit with their animal-focused holiday album: All I Want for Christmas is a Goat.

Fittingly, it features the shriek-filled vocal stylings of a group of festive farm animals bleating out classics like “Jingle Bells,” “Rudolph the Red-Nosed Reindeer,” and “O Come All Ye Faithful.” The recording may sound like a silly novelty release, but there's a serious cause behind it: It’s intended to remind listeners how the animals benefit impoverished communities. Goats can live in arid nations that are too dry for farming, and they provide their owners with milk and wool. In fact, the only thing they can't seem to do is, well, sing. 

You can purchase All I Want for Christmas is a Goat on iTunes and Spotify, or listen to a few songs from its eight-track selection below.

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