Happy Halloween Eve! It’s the perfect time of year for lovers of thrills and frights. Whether you’ll be spending your night out partying or staying in for a scary movie and some candy, take a minute to celebrate the natural horror of our planet with these spooky biology facts.
Bone worms
Deep beneath the ocean’s surface lay the Osedax — a genus of deep-sea marine worms that survive by consuming the skeletons of deceased animals on the ocean floor. The Osedax, commonly referred to as bone-eating worms, take their name from the Latin words “bone devourer.” A truly eldritch creature, the bone-eating worm has no mouth or stomach. It also lacks a gut, eyes and legs.
Osedax primarily feed on the lipids hidden deep inside of bones, and they are uniquely adapted for their chosen food source. Once an Osedax settles on a bone, it secretes an acid through specialized mucus-covered root tissues to dissolve the bone’s external layers to access the lipids within. Inside a specialized organ called a trophosome, Osedax rely on an endosymbiotic bacteria, known as Oceanospirillales, to help break down and digest the complex nutrients dissolved by the worm’s root acids.
Despite their terrifying nature, Osedax act as ecosystem engineers and enhance the biodiversity of bones they inhabit by increasing their structural complexity. This selfless act allows microfauna to inhabit otherwise inaccessible regions of the internal bone, contributing to the ocean floor’s strange and alien world.
Zombie ants
The subject of the award-winning video game and TV adaptation “The Last of Us,” Ophiocordyceps unilateralis is a specialized parasitic fungus that infects carpenter ants. In recent years, it has seized the popular imagination as the source of an imagined zombie apocalypse.
Of course, the real-life Ophiocordyceps fungus differs from its fictional counterpoint. For one, it does not infect the brains of its victims. Instead, spores from the forest floor infect unsuspecting ants by forming a mycelial network around their muscle fibers. From there, the fungus secretes chemical compounds that compel the ant to leave and seek out a plant or other tall object to climb. Once found, the fungus forces the ant’s jaws to clamp down on whatever it has climbed to secure its body, before it eventually withers away. After the ant dies, a fruiting body sprouts from the back of the ant’s head, releasing spores across the ground below. These spores infect more ants, and the cycle continues.
A fungal zombie outbreak from Ophiordyceps is unlikely, according to the Yale School of Medicine. Not only is the fungus too simple to infect the human body’s more complex musculature, but we are simply too hot for the fungus to handle. It would burn up in our bodies before taking over the world!
Frozen viruses
From the ice comes a slightly smaller “Thing.” Warming temperatures in the world’s polar regions have reached the icy tombs of innumerable microscopic killers. Permafrost — sediment that remains frozen solid for years at a time — has stored a record of the evolution of life on our planet. Due to its frozen nature, organic matter buried in the sediment can remain almost perfectly preserved. In the past, scientists have been able to exhume the bodies of wooly mammoths, humans and even a full penguin colony. Now, however, scientists have been focusing on the bacteria and viruses found frozen within the soil. In 2014, scientists were able to revive a dead virus, which was able to target amoeba cells. The experiment has since been replicated for other viruses.
The threat of a time-traveling viral outbreak is not theoretical. In 2016, an anthrax outbreak in Siberia affected dozens of humans and more than 2,000 reindeer between July and August. It was later linked to the deeper thawing of permafrost during exceptionally hot summers, which allowed old spores of Bacillus anthracis to resurface from old burial grounds and animal carcasses. As the climate continues to warm, what other horrors may crawl their way out of the arctic?
Serial-killer birds
This column would be remiss if it didn’t mention at least one type of bird. Butcherbirds, distinguished by their heavy, hook-like beak, are carnivorous songbirds known for impaling their prey on sharp objects such as thorns, branches or barbed wire. To nobody’s surprise, these avian murderers hail from Australia.
Although butcherbirds are generally insect eaters, they will not hesitate to feed on and display small lizards, mice and other vertebrates. Butcherbirds are not just senseless killers, however. They impale their prey for several reasons. For larger prey, external support is sometimes needed to allow the much smaller bird to feed on the carcass. Butcherbirds will often store away kills for later, turning bushes into a gruesome natural equivalent of a pantry. More bizarrely, the display of dead prey is used as a mating incentive.
Butcherbirds do have a sweet side. They are known to sing complex, high-pitched songs, which are used to defend their year-round group territories. Unlike birds of extratropical Eurasia and the Americas, both sexes sing prolifically. Gender equality amongst butchers — who would have thought?