As the female Osedax worm swims nearly 4000 meters below sea level in search of decaying whale bones to eat, her male equivalent--almost 100,000 times smaller than her--clamors to latch onto her body. He wriggles himself into her translucent tube alongside hundreds of other dwarf Osedax dudes, and a matriarchy flourishes.
Scientists found the first of these odd undersea worms 12 years ago while remotely patrolling the bottom of the ocean. The worms lack teeth and guts; they consume bones by secreting an acid that dissolves them and ingest the protein and fat through their skin. All variations of the worm seemingly follow the same mating pattern: hundreds of thirsty boys scramble to attach to a large, stable girl. A recent discovery from the Scripps Institution of Oceanography in San Diego, however, has scientists celebrating a more self-sufficient male--what they call the Osedax priapus, or 'penis worm'.
In a recent issue of Current Biology, marine biologist Dr. Greg Rouse of the Scripps Institution of Oceanography, along with his colleagues from the Western Australian Museum, Monterey Bay Aquarium, and the University of Copenhagen, detailed their discovery of the weird worm and its apparent evolutionary gene reversal. When it comes to the 'regular' Osedax species, Dr. Rouse explained that the guys depend on the girls. Osedax males land on women instead of finding their own food, and they're like human men in other ways, too: "The males are basically arrested babies," he said. They are 'dwarf males', who exist solely to find a female and ejaculate onto her. "They just invert their yoke to make sperm and fertilize their eggs," Rouse continued. "Then they die."
Unlike 'regular' Osedax males, the newly discovered variation of the worm, the O. priapus, acts like a man with bigger balls. Although it's not equivalent in size to its female counterpart, the O. priapus says no to mooching and goes in search of its own cartilage to consume. Once the males find that bone, they are stuck to it. Being anchored to their bone proves a problem for the O. priapus, as chicks are hard to come by. The solution is something out of an E.L. James novel or a festival in Kawasaki: "Their body is effectively a penis," said Rouse. Rather than doing the work of courting their female, the nearly 3 centimeter long phallic creatures extend and erect up to 10 times their size, until they discover something appropriately mate-able.
A quick Internet search leads to pages and pages about 'zombie worms', but according to Rouse, that nickname is inaccurate: "Zombies eat brains, and these creatures eat bone," he said. "It sounds cool, but it doesn't make much sense."
'Bone-devouring dick worm' sounds cooler, anyway. (Os = bone, edax = devour and priapus = penis).
In Greek Mythology, Priapus was somewhat of a frat legend. Born to wine god Dionysus and love goddess Aphrodite, the well-endowed god of fertility's small frame cowered behind a grossly disproportionate dick. "We decided that the best way to codify the species was to name it after the Greek God who's personified as having an erect penis," Rouse said. "It made a lot of sense." As marine scientist and "Sex in the Sea" blogger Dr. Marah Hardt wrote for Deep Sea News, "Why have a penis, when you can be a penis?"
Shockingly, scientists love studying the worm for reasons other than his massive boner. The new, larger worms prove an evolutionary reversal never before seen by man. "These little males effectively fought the matriarchy by devolving," Rouse told me. Based on evolutionary tree mapping, the marine biologists categorized the new discovery as neither primitive nor derived.
"It turned out that the dwarf males were the primitive system, and the new one, where the male was big and eating bone like a female, that was a complete reversal evolutionarily," Rouse said. "It's the first reversal case we know of."
This means the genes that made up the original Osedax species were not fully discontinued over time, proving to scientists the possibility of full gene reversal, as well as the need for ongoing study.
To celebrate the discovery of the bizarre, bone-eating, gene-reversed penis worm, Rouse and his colleagues popped Champagne and partied. "Every time someone does a new deep sea expedition, we usually find new things," he said. "There are always prizes waiting there for us."