Biodiversity Patterns in Melanesian Coral Reef Fish: New Research with Old Naturalists
Old naturalists are my jam. I dedicated my PhD dissertation to a 19th century botanist who had spent her childhood following Thoreau around the Concord woods. I have a soft spot for research that draws on the work of older ecologists, for data that was handwritten before the advent of ballpoint pens, for 21st century papers based on museum natural history collections.
This nostalgia is well-timed: museum collections are increasingly digitized and freely available online, and the Biodiversity Heritage Library is doing the same for scientific literature on biodiversity. Just as my kind of fieldwork no longer requires taking the steamship to downeast Maine and a buckboard on wild roads between logging communities, my scholarship is not dependent on scouring the library stacks for a particular volume or traveling to the archives of a natural history collection to comb through specimens for just the right sample. In the 21st century it is significantly easier to be an armchair laptop historical ecologist.
Easier, but not easy. “Natural history and collections seem to be a bit of a hard sell when it comes to the ecological literature, which surprised me,” says Dr. Kathryn L. Amatangelo. She and Dr. Joshua Drew just published a PLOS ONE paper using coral reef fish data from museum collections records, peer reviewed literature including fish check lists, and biological inventories. The biodiversity pattern they were attempting to analyze and understand — that reef fish diversity in the Indo-West Pacific decreases along a longitudinal gradient from species-rich Papua New Guinea to species-poor American Samoa — was described in 1906.
Amatangelo laments, “It seems almost passé to look at old collections and think about how and why long-dead historians collected their data. When you try to combine that with statistics and scientific analyses people seem to get a little squirrely.”
Drew and Amatangelo’s paper “Community Assembly of Coral Reef Fishes Along the Melanesian Biodiversity Gradient” applies modern ecological theory and big data statistical tools to observations recorded by David Starr Jordan, a Victorian-era ichthyologist who was both the founding president of Stanford University and a suspect in the possible murder of Jane Stanford. If that legacy is not problematic enough, he was also into eugenics. Thanks to the efforts of Biodiversity Heritage Library (BHL), we can read Jordan’s 1906 paper “On a Collection of Fishes from Fiji” where he notes the diminishing diversity of fish as you travel across Melanesia. Drew remarks, “historical ecologists are always looking for old species lists, and it was super cool to find that he worked in my study system in Fiji.” Drew describes a Jordan as “an ichthyological hero of mine, a complex and not unproblematic figure”: Jordan’s writing on ichthyological biogeography and community change, his system for organizing ichthyological collections and his service on the US Fish Commission, a precursor of NOAA, provide a foundation for the kind of work that Drew and Amatangelo so beautifully execute here.
In the pursuit of quantitatively describing this biodiversity gradient, Drew and Amatangelo compiled presence/absence records for 396 fish species in five taxa across 7 countries. As Drew describes it, this dataset was created from “a massive literature search from collections-based and peer-review based lists that were then double-checked with FishBase.” They looked for agreement across all three datasets (collections, literature, and FishBase), which gave them more confidence in the data since it was not susceptible to the biases present in only one dataset. Amatangelo is a community ecologist with a plant background, she partnered with Josh Drew through a twitter connection, bringing statistical savvy to these new-to-her taxa and ecosystems. I asked her what it was like to work with unfamiliar study species in this project. “One downside was that things that were intuitive to Josh, such as why some traits are important, was a bit of a mystery to me. That could also be considered a positive, though, because it meant that Josh had to be able to explain WHY they were important, which helped in writing the paper.”
The paper’s ultimate goal was to illuminate the processes behind the reef fish biodiversity pattern to inform conservation efforts. Drew acknowledges that their conclusions are not ground-shattering — the biodiversity gradient was described 110 years ago, and likely broadly known before then in local communities. “But it’s nice to put a p-value on it,” he says. “Natural history and traditional ecological knowledge are not always recognized because they don’t come with a p-value, so here we did that. We probably could have told you the same result before, but this adds weight to the management recommendations.” Those management recommendations include collaborations across Melanesia to more efficiently share resources and partition the region into functional biodiversity groups.
Through the power of twitter, digitization, and online collections two modern ecologists were able to build on a paper from 1906 and study Melanesian coral reef fish diversity from their laptop screens in the United States. So much of this data would be instantly recognizable to Jordan, but so little of the actual process of collaborating, compiling and analyzing data, and writing a paper has remained constant since 1906.
Drew reflects on this revolution in his recent correspondence to Nature Ecology and Evolution: “Digitization of museum collections holds the potential to enhance researcher diversity.” He and coauthors write that “the advent of digitization (open access to images and specimen data) now makes a wealth of biodiversity information broadly available…Digitization allows access to museum holdings to those for whom collections have typically been out of reach.” The concentration of collections in the Global North is a reflection of our discipline’s role in the history of exploration and colonialism. Untangling this broader context of past research is perhaps the most impressive, thoughtful work that a historical ecologist could pursue. In two papers this fall Drew has managed to both uphold the ichthyological legacy of Jordan, and articulately argue that the museum collections Jordan once organized in his spare time from being abhorrently racist, could be, in digital form, a force for decolonializing science.
Drew, Joshua A., and Kathryn L. Amatangelo. “Community assembly of coral reef fishes along the Melanesian biodiversity gradient.” PloS one 12, no. 10 (2017): e0186123.
Drew, Joshua A., Corrie S. Moreau, and Melanie L. J. Stiassny. “Digitization of museum collections holds the potential to enhance researcher diversity.” Nature Ecology & Evolution (2017):10.1038/s41559-017-0401-6