Published: October 18, 2017

Chisels, Hammers, and Science: Woodworking for Clams

Janet Voight, Associate Curator of Invertebrate Zoology, Negaunee Integrative Research Center

This is the ninth in a series of posts by Associate Curator of Invertebrate Zoology Janet R. Voight as she heads out on an expedition to Norway. There, she and colleagues will look for a wood-boring clam, Xylophaga dorsalis, to study its, well, poo. Read the first post and stay tuned for upcoming posts to find out what they discover.

My fellow researcher, Reuben, and I have been scouring the Norwegian coast for driftwood with boring clams. After four days, we had gathered a nice bunch of wood that we thought was likely to have shipworms, or even—just maybe—our target species, Xylophagadorsalis. The issue is, of course, how to find out if they do. We’re at a field station where there are no X-ray machines or CT scanners, so we have to do it the traditional way: pick up our woodworking tools. For the last two days, we have been using chisels and hammers to split the wood apart lengthwise to see what, if anything, might be inside. Sounds simple, doesn’t it? The right tools, well-applied, should make the wood pop apart, especially if the clams have done some work for us and bored into the wood. The truth, as in so many things in life, is far different. 

One piece of wood, admittedly far taller than Reuben, took us seven hours one day and three hours the next day to take apart. The work is slow and careful. We’re also looking for shipworms, Reuben’s specialty. These bivalves line their boreholes with a thin layer that forms a calcium-rich wall, so we want to get them out intact. At the tip of the siphon are hard little structures called pallets that are currently believed to be the only way to identify the animals. The shell and features of the siphon do not actually help identify the specimens, despite being most of the animal. So when you open the length of wood and encounter part of a siphon, you have to follow it to its tip to figure out what it is.

So far, we have two species and about 20 specimens after 10 hours of labor by two wood-boring specialists. (At times like this, I ask myself: Why didn’t I pick something else to be an expert in, like lichens that grow on everything, including car doors?!) One special surprise after all that work was one complete, though empty, shell of Xylophaga dorsalis. It’s about half the size I’d like to see, and it looked as if it had only recently died. Our efforts show that perseverance pays off. Though the numbers may seem low, we’re studying material that no one else does—isn’t that what you expect from The Field Museum?

Read on in Part 10: Searching for Sunken Treasure in the Fjords of Norway.

Funding for this project was provided by the Robert A. Pritzker Center for Meteoritics and Polar Studies established by a grant from the Tawani Foundation.

Janet Voight
Associate Curator of Invertebrate Zoology

Janet Voight, Associate Curator of Zoology, is a specialist in cephalopod mollusks, especially octopuses. In terms of where she works, it is the deep sea. If you work in the deep sea, there are times when you need to be a bit of a generalist, which is how Janet got interested in the wood-boring bivalves, the Xylophagaininae, and their apparent predators, the enigmatic echinoderm, Xyloplax. Discovery reigns supreme in the deep sea, as we know less about it and the animals that live there than we do about the back side of the moon. Janet's work is building the framework that offers to change that situation, that framework of course being based on specimens collected at sea, and available for study at the Field Museum.


  • Deep Sea Biology and Evolution
  • Cephalopod Evolution & Ecology
  • Wood-boring bivalves of Xylophagainidae
  • Taxonomy and Systematics
  • Deep-Sea Biogeography
  • Quantitative Morphology