It may sound harsh, but a natural history collection in a museum is almost worthless if it is not properly catalogued. Anyone who has spent even a short amount of time in a natural history collection can attest to the usefulness of well-curated collections. But sometimes, you open a specimen drawer, and immediately recognize a label with an outdated species name. Or even worse, you use the specimen in a study and don’t realize it is labeled wrong. Errors and mistakes like this are not the fault of the museum staff managing these immense collections, or the scientists themselves, but result from combination of factors that coalesce into a big fat mess when the accuracy of collections labels are systematically investigated.
Researchers at Oxford University and the Royal Botanic Garden Edinburgh examined tropical plants to assess just how many specimens are mislabeled and misidentified in herbaria around the world. In a paper published this week in Current Biology, Zoë Goodwin and colleagues evaluated 4500 specimens of African gingers from 40 herbaria in 21 countries and found at least 58% of the specimens had the wrong names associated with them. But how does this happen?
The authors point to a variety of factors that could lead to the extensive errors in museum collections. For one thing, major taxonomic revisions of groups are frequently needed but rarely completed. It wasn’t until a detailed monograph was done for the group of African gingers that the accuracy of labels could even be assessed. The authors also note with collections growing by leaps and bounds, specifically with the number of specimens in herbaria doubling from 1969-2000, it is impossible to keep up. It is just simply too much for the available experts to handle.
Another interesting problem is specific to the field of botanical collection. Often a single plant is divided into several samples and sent to a variety of herbaria for cataloging. Goodwin found that when the specimens from the same plant were chased down, 29% of them had different names in different herbaria. Simply put, many of these plants look very similar and can be difficult to identify. Again, there is just too much material out there for experts to see and assess to always be accurate in their ID. Although this is a study done with plants, this problem surely extends to all groups studied in natural history museums. Insects, the most abundant and diverse group on Earth, are sure to have considerable problems with accuracy of specimen labeling.
In 2004, legendary biologist E.O. Wilson wrote: “There are at present, at rough estimate, ca. 6000 taxonomists at work worldwide on all organisms combined.” Considering there are approximately 1.2 million species currently identified and upwards of 8.7 million predicted to actually exist on Earth, only having <10,000 scientists dedicated to naming millions upon millions of species with accuracy makes the task next to impossible. Although that was 11 years ago, since then there has not been an abundance of resources focused on promoting the field of taxonomy, often viewed as antiquated in the age of big data and rapid full genome sequencing.
Entomologist Quentin D. Wheeler writes in The New Taxonomy: “The taxonomy crisis is to a large extent a funding crisis. Taxonomists have proper techniques for describing and identifying species, but taxonomy as a discipline lacks the necessary funding for accomplishing the task.” A PhD level of expertise is often needed to be a qualified taxonomist, so the amount of money that needs to go into taxonomic training and research is not trivial. And while some think moving to a DNA based identification system is more useful, genetic databases like Genbank are also riddled with errors and mislabeled sequences. As Louisiana State University ichthyologist Prosanta Chakrabarty writes in a 2013 publication, when depositing sequences on Genbank, “The taxonomic determination remains solely the responsibility of the submitter of the sequences.” He goes on to say that once these errors are made, they are hard to discover and even harder to stop from propagating.
Goodwin et al. suggest increased digitization of collections—this way, more experts from around the world can identify specimens more readily without having to travel to collections. They also suggest that DNA analysis should be integrated into taxonomy studies. If these efforts are combined, it is very likely the world’s taxonomy crisis can be better addressed. Nevertheless, the lack of funding for taxonomic research despite its status as a “fundamental discipline” will continue to jeopardize the task of exploring and describing the life on our mysterious planet.
This post originally appeared on forbes.com/science