“How would you like to go to Curaçao?” These were not the words I expected to hear when I answered my phone after the third consecutive call from an “Unknown Number” on Monday night. Thirty-six hours later, I was dragging a heavy metal object through the airport on my way to join the search for shark dermal denticles. My surprise journey with the Grab Sampler is only part of what is becoming an epic battle against Murphy’s Law in the ongoing Denticle Quest of the Baseline Caribbean team. This post details some of the obstacles the team has already overcome. You can watch many of these events unfold in the live-science videos.
Obstacle 1: Small Denticles
Shark dermal denticles are small—smaller than a grain of salt—and you might think that collecting denticles would be harder than finding a needle in a haystack. However, their small size helps the Baseline Caribbean team narrow down potential denticle sites. In areas washed by waves or current, any denticles would likely be swept away. Consequently, denticles only accumulate in low-energy locations where they can settle undisturbed. These sheltered locations are what the team is seeking in “1: Looking for Sites.” Silty sediment is an indication that the water is quiet enough for the denticles to remain.
Obstacle 2: Deep Denticles
The team came prepared to scuba dive in and dig for denticles by hand. You can see them at work in “2: The Perfect Sediment.” However, it turns out that in Curaçao at least, much of the “perfect sediment” is deeper than the divers are prepared to go. So, how to collect these deep silty sediments without diving? The Grab Sampler provides a solution: it is a heavy metal scooper that can be lowered over the side of a boat to collect deep sediments. Problem solved, right? …except that the Grab Sampler remained in Panamá. Lucky for me, the easiest way to get it to Curaçao was for me to bring it. I got to travel to Curaçao, several customs officers got to learn about the mysterious metal object in my luggage, and the Baseline Caribbean team got back to work, digging denticles.
Obstacle 3: The Grab Sampler works! And then it doesn’t.
The Grab Sampler may look like a boring metal scoop, but it is actually an instrument of high drama and suspense. After it’s lowered over the side of the boat, it sinks into the blue depths and disappears. The line keeps feeding downward, down past the rising bubbles, down farther until suddenly it goes slack: the Grab has hit bottom. Quickly, all hands go to the rope, everyone sweating to pull it back up and wondering what it will bring. That first retrieval, we all crowded around, watching as it surfaced, watching as Felix swung it over the side, leaning in to see… a single algae-encrusted shell deposited on the tray. The second go brought nothing. We tried a slower descent, than a faster one. We moved shallower, then deeper. Finally, we started bringing up the silty material we were looking for. Success! We danced the Denticle Dance, and our collection of sample bags started growing.
Unfortunately, that was not the end of the Grab Sampler’s drama. As we sent it down again, the wind picked up, pushing the boat over the descending line. The Grab Sampler must have dragged along the bottom, because when we retrieved it the sturdy metal was bent out of shape, rendering the instrument useless. As we research options for fixing the Grab, the team is back to diving for sediment in the sites that are not too deep.
. . .
Beyond these obstacles, the team has struggled against 75 million-year-old radiolarians (the backbone of the island is silica-rich rock made of ancient plankton skeletons, and as it erodes into the bays it makes the denticle search more difficult), wary property owners, Carnival traffic, difficult-to-find docks, and even an issue with the coast guard. Yet even when it seems that everything that can go wrong does go wrong, the team finds a way around the problem and the search for denticles continues. This is how science works—often it is the challenges that lead to creative problem solving, novel approaches, and interesting new questions. And sometimes when things go wrong, an intern gets to go on an unexpected trip to Curaçao.