Batter Up!
Expert knowledge and experience give "Big Hitter" plant collectors advantage in finding new species
Who collects new species of plants? That question was only anecdotally answered until a pioneering analysis by Daniel Bebber and colleagues published in the Proceedings of the Royal Society of London a decade ago. With museum and botanical garden records being digitized and made accessible on the internet, they recognized the opportunity to explore this question in a more scholarly way.
As they explain, discovering new plant species is a three-step process: (1) specimens are collected; (2) they are recognized as new; and (3) finally, they are described and named in a publication. While many new species are named by their collectors, many others end up in herbaria as unknowns where they site, often for years, until a botanist comes along with the appropriate specialized knowledge to recognize them as new.
Specimens of Nepenthes in the herbarium of the Muséum national d'histoire naturelle, Paris. Photographer: François MEY. CC BY 3.0.
They used type specimens to track the productivity of collectors. Types are the name-bearers of species, functioning as a kind of international standard used to verify that the name is being used correctly. Wherever the type specimen fits in the latest hypotheses about the number and boundaries of species, there follows the name attached to it.
They pulled together information about the collectors of 100,000 type specimens in their groundbreaking study. What they found was that a small number of incredibly productive collectors have made a disproportionate impact on the collection of new species. In round numbers, 50% of new species were collected by just 2% of collectors. On the flip side, a single type specimen had been collected by about 50% of collectors. They called these super prolific collectors “Big Hitters,” noting that this phenomenon is less pronounced today than in the past.
It turns out that Big Hitters get better and better at collecting new species as they go. This may be attributed, in part, to increased familiarity of the flora in areas being collected, as well as knowledge of plant species generally. Knowing common species on sight allows a collector to invest time collecting the unusual and rare.
Surprisingly, Bit Hitters did not focus on species-rich regions more than small-hitters. They did tend to collect in more countries, while specializing in a particular region. Something that surprised me was that Bit Hitters collected specimens from the largest number of families. There are exceptions, of course, such as one Big Hitter who focused specifically on orchids.
As an entomologist, I have seen both place and expertise triumph in collecting new species. When Terry Erwin, of the Smithsonian, began fogging the canopy of tropical trees, it literally rained new species. At another extreme is the finesse of special knowledge. For example, one of my students became the expert for an obscure family of mycophagous beetles. When he traveled to a location in Central America, that had been intensely collected for decades in support of ecological studies, he found that they had not collected a single specimen of the family he studied. Within a week, he collected several species, including some new to science. These beetles don’t show up in light traps or other mass collecting techniques, and his specialized knowledge of their habitat allowed him to zero in and find them efficiently. When a comparable study of insect types is done, it will be interesting to see whether the botanical pattern is repeated. Regardless, I suspect that as most species in a group become known that specialized knowledge becomes more important in ferreting out those elusive, last-to-be-discovered species.
Their conclusion was that expertise and experience, gained over many years of field work, play a critical role in making a Bit Hitter. Big Hitters are not necessarily first to explore a region. First collectors have an obvious advantage collecting the most common new species, but the most productive collectors work over many years to hone their skills. They wisely advocate recognizing individuals who show the potential to become big hitters and providing them support to do so. With 15-30% of flowering plant species yet to be discovered, the need for collectors is as important as ever.
The bottom line, especially as common and easily collected species become known, is that there may be no substitute for specialized knowledge and experience for the collecting phase of species discovery. With tens of thousands of species believed to be going extinct each year, and millions of species unknown to science, these are important lessons to be learned if we hope to complete an inventory of species before millions have been lost to extinction. We need more taxon experts and more big hitters. Batter up!
Reference
Bebber, D.P., Carine, M.A., Davidse, G., Harris, D.J., Haston, E.M., Penn, M.G., Cafferty, S., Wood, J.R.I., and R.W. Scotland (2012) Big hitting collectors make massive and disproportionate contribution to the discovery of plant species. Proceedings of the Royal Society, B, 279: 2269-2274.