Another future issue concerning collections is related to the development of metagenomics. Developed by microbiologists, this technique makes it possible to obtain global DNA samples from an environmental sample (soil, water, etc.) (Tringe and Rubin 2005). It does not distinguish between the individual organisms analyzed, but rather extracts the overall DNA of a given sample. It therefore does not allow us to return to individual specimens and to the material origin of the data obtained. When the sequenced taxa are unknown at the molecular level, they cannot be identified in a taxonomic sense and thus linked to the existing body of knowledge (Pellens et al. 2016, pp. 375–383). A huge study of plankton in the world’s oceans, for example, reports over 100,000 operational taxonomic units (OTUs) detected by metagenomics, of which only a little over 11,000, at best, are described with a name in the scientific literature (Vargas et al. 2015). Initiatives with similar implications are developing with respect to fungi, for which molecular identification is preferred to the uneasy linkage to traditional taxonomy that is difficult to conduct on microscopic organisms with limited access to direct sampling (Nilsson et al. 2019).
Initially, all these developments occur without too many problems because they are based directly on existing knowledge and the taxon naming system. Nevertheless, it seems quite obvious that a second cycle of knowledge acquisition, on the occasion of future studies, with mixed reference to traditional taxa and molecular entities defined in the meantime, may lead to a great confusion, a lack of global coherence and a lack of capitalization in knowledge.
Unfortunately, there is no miracle solution to this duality between collections or traditional taxonomy and metagenomics, except by organizing crossover studies between these different fields of activity and thus reinforcing the links between species, taxa and molecular OTUs. Collections remain as indispensable as ever in this context and it is simply necessary to ensure that the links with molecular data, which are already very lax, are, at last, adequately rewoven.
2.7. Conclusion
Natural history collections are alive and well and guarantee us a rich future of diachronic or large-scale scientific studies. The usual criticisms of their deficiencies or biases (Beck et al. 2012) do not hold if we rightly consider that we need to resample collections for every new study we conduct instead of considering that they should be improved according to an ideal universal protocol.
Their future study can be very fruitful but their future enrichment can very quickly become a problem and slow down significantly if we do not modify our behavior by making our data properly available and if we do not create the necessary bridges between collections, taxonomy and new forms of sampling. These are open science objectives which must be rigorously implemented in relation to the FAIR data concept.
The permanence and coherence of knowledge on biodiversity come at this price. All the knowledge we have on biodiversity is scattered in a huge and diverse literature and only the taxonomic names and the specimens that are potentially associated with them allow for this knowledge to be united.
2.8. References
Amano, T., Lamming, J.D.L., Sutherland, W.J. (2016). Spatial gaps in global biodiversity information and the role of citizen science. Bioscience, 66, 393–400.
Arino, A.H. (2010). Approaches to estimating the universe of natural history collections data. Biodiversity Informatics, 12, 57–62.
Ayris, P., Lopez de San Roman, A., Maes, K., Labastida, I. (2018). Open science and its role in universities: A roadmap for cultural change. LERU Advice Paper, 24, 1–31.
Beck, J., Ballesteros-Mejia, L., Buchmann, C.M., Dengler, J., Fritz, S.A., Gruber, B., Hof, C., Jansen, F., Knapp, S., Kreft, H., Schneider, A.-K., Winter, M., Dormann, C.F. (2012). What’s on the horizon for macroecology? Ecography, 35, 673–683.
Charles, H. and Godfray, J. (2002). Challenges for taxonomy. Nature, 417, 17–19.
Costello, M.J., Wilson, S., Houlding, B. (2012). Predicting total global species richness using rates of species description and estimates of taxonomic effort. Systematic Biology, 61, 871–883.
Costello, M.J., May, R.M., Stork, N.E. (2013). Can we name Earth’s species before they go extinct? Science, 339(6118), 413–416.
Dias Tarli, V., Grandcolas, P., Pellens, R. (2018). The informative value of museum collections for ecology and conservation: A comparison with target sampling in the Brazilian Atlantic forest. PLoS ONE, 13, xe0205710.
Feeley, K.J. and Silman, M.R. (2011). Keep collecting: Accurate species distribution modelling requires more collections than previously thought. Diversity and Distributions, 17(6), 1132–1140.
Fischer, R.A. (1930). The Genetical Theory of Natural Selection. A Complete Variorum Edition. Oxford University Press, Oxford.
Funk, V.A. (2004). 100 uses for an herbarium. Document, Division of Botany, The Yale University Herbarium, CT.
Funk, V.A. (2018). Collections-based science in the 21st century. Journal of Systematics and Evolution, 56, 175–193.
Garnett, S.T. and Christidis, L. (2002). Taxonomy anarchy hampers conservation. Nature, 417, 17–19.
Goodwin, Z.A., Harris, D.J., Filer, D., Wood, J.R.I., Scotland, R.W. (2015). Widespread mistaken identity in tropical plant collections. Current Biology, 25(22), R1066–R1067.
Grandcolas, P. (2017a). Loosing the connection between the observation and the specimen: A by-product of the digital era or a trend inherited from general biology? Bionomina, 12(1), 57–62.
Grandcolas, P. (2017b). The living species is not a natural kind but an intellectual construction. In Life Sciences, Information Sciences, Gaudin, T., Lacroix, D., Maurel, M.C., Pomerol, J.C. (eds). ISTE Ltd, London, and John Wiley & Sons, New York.
Justine, J.-L., Winsor, L., Gey, D., Gros, P., Thévenot, J. (2018). Giant worms chez moi! Hammerhead flatworms (Platyhelminthes, Geoplanidae, Bipalium spp., Diversibipalium spp.) in metropolitan France and overseas French territories. PeerJ, 6, e4672.
Le Bras, G., Pignal, M., Jeanson, M.L., Muller, S., Aupic, C. (2017). The French Muséum national d’Histoire naturelle vascular plant herbarium collection dataset. Sci. Data, 4, 170016.
Le Guyader, H. (2003). Classification and Evolution. Le Pommier, Paris.
Linnaeus, C. (1758). Systema Naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Editio decima, reformata, Tomus I. Holmiae, Laurentii Salvii.
Mallet, J. (2008). Hybridization, ecological races and the nature of species: Empirical evidence for the ease of speciation. Philosophical Transactions of the Royal Society B: Biological Sciences, 363(1506), 2971–2986.
Marshall, S.A. and Evenhuis, N.L. (2015). New species without dead bodies: A case for photo-based descriptions, illustrated by a striking new species of Marleyimyia Hesse (Diptera, Bombyliidae) from South Africa. Zookeys, 525, 117–127.
May, R.M. (1988). How many species are there on Earth? Science, 241 (4872), 1441–1449.
May, R.M. (2004). Tomorrow’s taxonomy: Collecting new species in the field will remain the rate-limiting step. Philosophical Transactions of the Royal Society of London B, 359, 733–734.
Meineke, E.K., Davis, C.C., Davies, T.J. (2018). The unrealized potential of herbaria for global change biology. Ecological Monographs, 88, 505–525.
Meyer, C., Kreft, H., Guralnick, R., Jetz, W. (2015). Global priorities for an effective information basis of biodiversity distributions. Nat. Commun., 6, 8221.
Mills, J.A., Teplitsky, C., Arroyo, B.,