So far in this series of posts on the uses of herbarium specimens in research (1,2,3), I’ve stuck to those that are most commonly discussed: taxonomic and floristic work, environmental change studies, and phylogenetics. But there are many other uses, with the variety increasing because digitization makes specimen information more easily available to a broader audience. There have been studies on the presence of plant pathogens in specimens, including fungal infections (Kido and Hood, 2019). Anther smut was found detected on specimens through visual inspection under a microscope (Antonovics et al., 2003). Recently, sensitive DNA sequencing techniques have made it possible to detect bacterial infections by differentiating between pathogen and host DNA. There is even Defense Department interest in such research. The Center for the Study of Weapons of Mass Destruction in Washington DC issued a report where they outline why natural history collections can be sources of information in the work of protecting against biological warfare.
Different groups of researchers look at herbarium specimens very differently. Those investigating fungi might focus on the roots, such as in a study about the successful extraction of arbuscular mycorrhizal fungal DNA from vascular plant roots. Other botanists have developed techniques for systematically evaluating the amount of herbivore damage to leaves by using a grid system (Meineke & Davies, 2019). While it’s common to find dead insects on a specimen, snails hiding out are more of a surprise. Researchers examining lichens and bryophytes from the Galapagos Islands found that 10% of 400 specimens had at least one of eight different micro-mollusk species adhering to them. There was even a new species discovered. It is not unusual for new plant species to be found among herbarium specimens (Bebber, 2010), but snails are another thing.
Specimens can also be useful before trips to collect more specimens; Kew Botanic Gardens has a handbook with specimen images as a guide for collectors. Searching databases for where a particularly narrowly endemic species was found in the past increases a botanist’s chances of finding it again. One approach is searching for associated species in locality information. Botanists are being encouraged to list such data to make specimens more valuable in ecological studies. Another way to enhance specimens is to link them to other types of data such as iNaturalist observations from the same locale. Heberling and Isaac (2019) describe how they are doing this at the Carnegie Museum of Natural History’s herbarium in Pittsburgh. The iNaturalist data can include photos taken on the site by citizen scientists. These visual records may document traits such as flower color and form that are difficult to preserve in dried specimens. There may also be information about the surrounding habitat. Having these items linked to specimens is a step toward the development of what is termed the Extended Specimen Network, with the specimen is at the center of linked resources providing information on the genetics, ecology, and morphology of the species (see earlier post).
Besides scientific uses, herbaria can also have what could be termed sociological uses. There are several ways in which digitization of natural history collections could lead to more diversity among researchers. Online access means that those interested in taxonomy who are living in developing nations can more easily access not only specimen data but related research through such portals as GBIF. This also makes it easier for them to find research partners in developed nations. A very different approach to expanding diversity has been employed by several institutions in the United States: enlisting those in juvenile detention centers and those recently released from such facilities in digitizing specimens. These projects not only provide employment, but also broaden the participants’ experience of science and of working with databases. It is a nice example of thinking more creatively about expanding the population of those interested in nature and opening up herbaria in novel ways. The iDigBio project held a webinar on this topic to make the natural history collection community aware of this approach, document the progress that has already been made, and encourage other ways to think outside the box in drawing people to natural history.
I haven’t mentioned using herbarium collections in outreach programs because I covered this in a recent post. However, I have recently come across a few examples that seem too good to ignore. The first is a “Hookathon: Hacking the Herbarium” at the Royal Botanic Gardens, Kew. This was an all-day citizen science event to digitize items in Kew’s massive collection of material related to Joseph Dalton Hooker, who led the garden for many years during the second half of the 19th century. This was also a means to advertise the collection’s existence and its variety, including specimens, manuscripts, letters, and drawings. At the University of Manchester in Britain, the herbarium opened its doors to students during the exam period for “well-being” events so they could unwind by drawing specimens and incidentally find out what a herbarium is about. I would like to end with a political, yes a political, example of outreach. A Tweet from the Georgia Southern University Herbarium reminded residents about voting and put in a plug for the state symbol, the peach, with a beautiful fertile specimen. This is outreach at its most creative.
Antonovics, J., Hood, M. E., Thrall, P. H., Abrams, J. Y., & Duthie, G. M. (2003). Herbarium studies on the distribution of anther-smut fungus (Microbotryum violaceum) and Silene species (Caryophyllaceae) in the Eastern United States. American Journal of Botany, 90(10), 1522–1531.
Bebber, D. P., Carine, M. A., Wood, J. R. I., Wortley, A. H., Harris, D. J., Prance, G. T., Davidse, G., Page, J., Pennington, T. D., Robson, N. K. B., & Scotland, R. W. (2010). Herbaria are a major frontier for species discovery. Proceedings of the National Academy of Sciences, 107(51), 22169–22171.
Heberling, J. M., & Isaac, B. L. (2018). iNaturalist as a tool to expand the research value of museum specimens. Applications in Plant Sciences, 6(11).
Kido, A., & Hood, M. E. (2020). Mining new sources of natural history observations for disease interactions. American Journal of Botany, 107(1), 3–11.
Meineke, E. K., & Davies, T. J. (2019). Museum specimens provide novel insights into changing plant–herbivore interactions. Phil. Trans. R. Soc. B, 374(1763), 1-14.