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“Zombie” Worms Mate Inside Whale Bones

In modern pop culture, zombies are everywhere, from TV shows like The Walking Dead to books like World War Z.

But when it comes to the creepy factor, Osedax worms—nicknamed “zombie worms”—beat out even the goriest movies.

A recent study reveals that these faceless, mouthless worms enjoy making sweet, sweet love inside decomposing whale skeletons that have fallen to the bottom of the ocean floor.

zombie worm picture
An adult female bone-eating worm. Photograph courtesy Norio Miyamoto/Naturwissenschaften.

 

Originally discovered off the coast of California in 2002, Osedax—whose name is derived from the Latin for “bone eating”—got its name for its peculiar living quarters: the bones of a decomposing gray whale. These deep-dwelling worms secrete acid to bore through the hard outer bones of whales and other large vertebrate skeletons to reach the nutritious oils within. (See “New Worms Eat (and Eat and Eat) Only on Dead Whales.”)

The weirdness doesn’t stop there. Unlike many species of animals, female Osedax worms are much larger than the males—so much larger, in fact, that 50 to 100 males can live inside the female in one of nature’s most bizarre harems.

The males’ sole purpose, as far as researchers have been able to figure out, are as sperm providers. But scientists still didn’t know exactly how these worms developed and reproduced.

The Bare Bones 

To study the worms’ mating process, Norio Miyamoto and colleagues at the Japan Agency for Marine-Earth Science and Technology obtained a set of whale bones from off the coast of Cape Noma, Japan. (See more pictures of bone-eating worms.)

The researchers added pieces of these bones to the petri dishes containing O. japonicus larvae of both genders. Six weeks after the female larvae moved into their new whale-bone homes, they began to pump out eggs, which were then fertilized by the dwarf males.

“This rapid sexual maturation of females, alongside the male dwarfism which was observed, enables the worms to reproduce effectively in the food-rich but highly isolated habitat of whale bones,” according to the study, published recently in the journal Naturwissenschaften.

Whale skeletons are often separated by huge distances, which would make finding mates difficult—hence, the females carry a lot of little males with them. (Related: “Dead Whale Contains a Bounty of Life.”)

The team also found that the newborn larvae could survive for ten days in the water without eating—allowing the young animals to drift until they find other promising corpses.

These findings help explain not only the function of the worms’ odd sexual behaviors, but also their success at rapidly colonizing dead whales around the world.

Kinky gets the job done—at least for these zombie worms.

Comments

  1. R
    September 9, 2:44 pm

    Beautifully weird

  2. Ritti chopra
    Kanpur
    June 13, 2013, 6:19 am

    really horriable

  3. Bonqueque
    Yo crunchy butt cheeks
    June 12, 2013, 11:09 am

    demm b cray as a mofo day all up in yo bones like they pay the bills DANG

  4. Bonqueque
    Yo mamas house
    June 12, 2013, 11:06 am

    Dem be lookin cray like foreal do that cray day be all like rawr ima have babies in yo bones

  5. Ignus Draklemagne
    Home
    May 28, 2013, 6:45 pm

    I wonder why does the zombie worm only seem to eat/mate in whales? Why not any other large, dead, and decomposing creature that happens to fall down to the dark abyss along with the rest of the deep-sea snow, such as a whale shark or sunfish?

  6. Xavier Huerta
    Houston,Tx
    May 23, 2013, 3:42 pm

    Wow

  7. c-dog
    May 16, 2013, 10:49 am

    so scary

  8. minecraft1029
    fremont
    May 9, 2013, 10:55 pm

    zombies are bad like dumb

  9. Brosive
    May 8, 2013, 12:35 pm

    Dang bruh! Das messed up.

  10. Naelahnyi
    1826 lacombe avenue
    April 3, 2013, 9:32 am

    amazing story.so intresting and factual.

  11. IMRAN ELAHI
    PAKISTANI
    April 1, 2013, 11:58 am

    THANKS TO THIS CAHANNAEL IT SURVIVIE IMAZING HISTAORY

  12. Trenton
    SC, USA
    March 28, 2013, 8:33 am

    Fascinating! Given that Osedax specimens are faceless and mouthless, how do they eat, exactly? I am wondering if they excrete the equivalent of bile salts so that they can absorb fatty acids in micellar form through specialized cells. In other words, is the Ocidex “digestive tract” on the outside of their bodies? I’m guessing that the ionic strength (salt concentration) of sea water would make absorbing free fatty acids difficult if not impossible. Thanks.

  13. Hodaifo
    Mozambique.
    March 28, 2013, 2:52 am

    Is good.