Figuring it out: part 2

Another day, another specimen. Friends, this is science.

The ultimate sponge book!
I'm working with an intern right now to identify all the species that I collected from stones in the Arctic deep sea last summer. I had been analyzing hard-bottom communities in the Fram Strait for years and even written papers on the distribution patterns of sponges, soft corals, and anemones on dropstones and a boulder reef in the area, without being able to name most of the species. I came up with my own descriptive names to call them - flat white sponge, bulb-tipped clump, splotch. But those colorful morphotype descriptors were just not going to cut it. Now that I have some physical specimens, we're seizing the chance and figuring out the proper names.

One of the biggest challenges in identifying specimens is gathering reference materials. Some taxonomists enjoy writing reference books, while others choose to publish their results in individual papers. Some taxa are extremely well-studied, others less so. It can take a while to hunt everything down. Plus, taxonomists are becoming a rare breed in the 21st century, so some of the best books are out of print. For example, the best Arctic bryozoan identification book is by a Soviet biologist and has been out of print for years, so when I found it for sale online, I pounced! Not your average impulse buy, but totally worth it.

Radiella sol on a stone in the Fram Strait. Photographed
using ROV Phoca.
My intern and I had a few victories over the last week. First, we found the most beautiful, thick, comprehensive, multi-volume identification guide ever. It's for sponges, and this book takes you from "Hm, I think this animal is a sponge" all the way to its genus name using the keys, descriptions, and illustrations in its pages. I was so excited to find it! For any taxonomists reading this blog: please rally your colleagues and write a comprehensive identification guide for your favorite phylum. I will buy it. If you're a sponge taxonomist, thank you for making my life just that much easier!

Using the sponge book, we were able to identify one of the most common species of sponges on rocks in the Fram Strait to species. "Half-and-half sponge" can now be called by its proper name in my lab: Radiella sol.

After celebrating our sponge victory, we pulled out another specimen: a solitary ascidian that was pretty common on the stones. I've told you about ascidians before, but most of them around Woods Hole are colonial (they live in large groups of interconnected clones) instead of solitary (single, large individuals). I found a paper about ascidians in the Rockall Trough, which is south of our study sites but tends to have many of the same species. My intern and I started looking through the illustrations in the paper, and even though our specimens looked similar to many of the species depicted there, we were stuck.
The ascidian on a stone in the Fram Strait. Photographed
using ROV Phoca.

I decided to cut one of the specimens open, and my mind flashed back to something I had learned in grad school: you have to dissect ascidians to identify them! Thankfully, I still had my PhD advisor's instructions for dissecting solitary ascidians on my laptop. We followed the instructions carefully, pulled the ascidian out of its thick outer tunic, and laid it in the dish. Immediately, it started to look like one of the species in the paper. We confirmed our suspicions by reading the full description, and voila! Adagnesia charcoti - another species identified.

Many times, scientists are portrayed in popular media as walking databases. They identify every species on sight and rattle off information like it's no big deal. Large mental databases do exist (I've been known to identify my fair share of species on sight, and I've met people capable of much more), but they take time to build. Science is a process. We spend most of our time in the lab not going directly from question to answer, but working our way through the process and figuring things out.

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