This Rare Shipworm Is Not Safe for Work

Matthew Modoono / Northeastern University
Matthew Modoono / Northeastern University

Scientists recently found a massive, suggestively shaped shipworm squelching through the mudflats of the Philippines—the first time the creature has been spotted alive. They described the “beefy, muscular” animal in the Proceedings of the National Academy of Sciences.

Shipworms are extraordinary creatures. They’re best known for making marine archaeologists' lives harder by riddling sunken ships with holes. As our planet's oceans heat up, so, too, does the rivalry between researchers and shipworms, which are moving fast into now-comfortably warm waters full of Viking ships. It's an "alarming scenario," the leaders of Denmark's Wreck Protect project note on their site.


Michael C. Rygel via Wikimedia Commons // CC BY-SA 3.0

Shipworms aren't true worms, but bivalves like mussels and clams. But where a clam’s slimy foot is relatively short, the shipworm’s just keeps going. The majority of shipworm species are “very delicate, translucent, usually white, beige or pink,” lead investigator Daniel Distel of Northeastern University in a statement. “They’re mostly small, a few centimeters long.”

And then there’s Kuphus polythalamia, which is decidedly … not delicate. People have been finding its rigid, tusk-like, 3- to 5-foot-long shells for hundreds of years, so scientists knew the giant shipworm existed. They’d just never seen one alive.

Then a Philippine television channel aired a documentary about a strange lagoon where long, stiff stalks emerged like fence posts from the mud, and local people ate the shipworm as a delicacy. A researcher sent the video to Distel and his colleagues, all of whom got pretty excited.

"For a biologist who is interested in these bivalves, it's like a unicorn," said senior author Margo Haygood of the University of Utah.

Distel, Haygood, and their team went on an expedition to the muddy lagoon, and there they found the shipworms. They rinsed off one specimen, packed it in a PVC pipe, and ferried it carefully back to the lab for closer inspection.

"When I took that thing out of the tube, there was a collective gasp among the whole group," says Distel, "along with quite a number of expletives." The shipworm was “like a baseball bat.”

The creature from the sticky lagoon is more than just an oddity. Unlike other shipworms, it doesn’t seem to eat wood—or anything else, for that matter. It’s not a matter of scarcity; the lagoon where the researchers picked their K. polythalamia was full of rotting wood. But that bounty goes untouched, and the giant shipworm’s digestive organs have withered to nearly nothing. So how does it live?

By making friends with microbes. The shipworm "consumes" hydrogen sulfide gas, a natural byproduct of wood decay, which is then processed into nutrients by the bacteria living within its enormous gills.

If it doesn't feed on the wood itself, why bother with wood at all? The researchers believe K. polythalamia is a descendent of a wood-eating ancestor, but that over time it formed this unique relationship with the bacteria it hosts. "We believe that somewhere along the line a shipworm acquired a sulfur-oxidizing bacteria as a symbiont, and it was able to get energy not just from the wood but also from the inorganic gas hydrogen sulfide coming from the wood as it rotted," Distel said. "Eventually the new symbiosis completely replaced the old symbiosis."

Now there's a way to make nice with the archaeologists.

Wayfair’s Fourth of July Clearance Sale Takes Up to 60 Percent Off Grills and Outdoor Furniture

Wayfair/Weber
Wayfair/Weber

This Fourth of July, Wayfair is making sure you can turn your backyard into an oasis while keeping your bank account intact with a clearance sale that features savings of up to 60 percent on essentials like chairs, hammocks, games, and grills. Take a look at some of the highlights below.

Outdoor Furniture

Brisbane bench from Wayfair
Brisbane/Wayfair

- Jericho 9-Foot Market Umbrella $92 (Save 15 percent)
- Woodstock Patio Chairs (Set of Two) $310 (Save 54 percent)
- Brisbane Wooden Storage Bench $243 (Save 62 percent)
- Kordell Nine-Piece Rattan Sectional Seating Group with Cushions $1800 (Save 27 percent)
- Nelsonville 12-Piece Multiple Chairs Seating Group $1860 (Save 56 percent)
- Collingswood Three-Piece Seating Group with Cushions $410 (Save 33 percent)

Grills and Accessories

Dyna-Glo electric smoker.
Dyna-Glo/Wayfair

- Spirit® II E-310 Gas Grill $479 (Save 17 percent)
- Portable Three-Burner Propane Gas Grill $104 (Save 20 percent)
- Digital Bluetooth Electric Smoker $224 (Save 25 percent)
- Cuisinart Grilling Tool Set $38 (Save 5 percent)

Outdoor games

American flag cornhole game.
GoSports

- American Flag Cornhole Board $57 (Save 19 percent)
- Giant Four in a Row Game $30 (Save 6 percent)
- Giant Jenga Game $119 (Save 30 percent)

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The Reason Your Dog Follows You Everywhere

Crew, Unsplash
Crew, Unsplash

Depending on your mood, a dog that follows you everywhere can be annoying or adorable. The behavior is also confusing if you're not an expert on pet behavior. So what is it about the canine companions in our lives that makes them stick by our sides at all times?

Most experts agree on a few different reasons why some dogs are clingy around their owners. One is their pack mentality. Dogs may have been domesticated thousands of years ago, but they still consider themselves to be part of a group like their wild ancestors. When there are no other dogs around, their human family becomes their pack. According to Reader's Digest, this genetic instinct is also what motivates dogs to watch you closely and seek out your physical touch.

The second reason for the behavior has to do with the bond between you and your pet. As veterinarian Dr. Rachel Barrack told the American Kennel Club, puppies as old as 6 months can imprint on their human owners like they would their own mothers. Even older dogs will bond with the humans in their lives who show them care and affection. In these cases, a dog will shadow its owner because it sees them as an object of trust and security.

The last possible explanation for why your dog follows you has more to do with your treatment of them than their natural instincts. A popular training tactic is positive reinforcement—i.e. rewarding a dog with treats, pets, and praise when they perform positive behaviors. The point is to help your dog associate good behaviors with rewards, but after a while, they may start to associate your presence with rewards as well. That means if your dog is following you, they may be looking for treats or attention.

A clingy dog may be annoying, but it usually isn't a sign of a larger problem. If anything, it means your dog sees you in a positive light. So enjoy the extra companionship, and don't be afraid to close the door behind when you need some alone time.