Why do museums have natural history collections?

Fig. 1. View of an insect collection area in the Manchester Museum.

Natural history collections include specimens from the subject areas of zoology, botany, entomology, palaeontology and mineralogy (Fig. 1), as well as any documentation associated with them (e.g., card indexes of related museum collections, field notebooks, correspondence files, diaries, etc). Such collections exist not only in museums and herbaria, but also in botanical gardens, arboretums, zoos and aquaria. However, live animal or plant collections are outside the scope of this short essay. It is worth mentioning though that more than 70 known British zoos and aquaria house some 64,000 vertebrate species.

There are more than 200 public and private museums in the UK with natural history collections, 50 of them hold significant foreign material. Recent estimates suggest that the number of natural history specimens in British museums exceeds 100 million. Worldwide, there are more than three billion! Many of the natural history collections in the UK, such as those of the Natural History Museum in London, the Natural History Museum of Oxford University or the Manchester Museum, are of global importance. However, the vast proportion of large museum collections (c. 95%) are kept in storage, behind the scenes, and their full diversity will never be displayed. But does this mean that the majority of collections are not used? Far from it, these collections are stored carefully because of their dual role as a resource for research and for education (see also here).

Collections as biological libraries

The fundamental value of natural history collections is related to our understanding of the Earth’s diversity. Taxonomic museum collections underpin the accumulation of biological knowledge, providing references to discovered natural units (species), and indeed represent an ecological database through the data associated with specimens. Therefore, natural history collections act as ‘biological libraries’, in which a separate specimen can be seen as a prototype of a letter and an individual collection as that of a paragraph or section in the ultimate ‘Book of Knowledge’.

Natural history collections represent an irreplaceable resource for taxonomic and biodiversity research. Such research aims to answer three fundamental questions: (1) what is the organism under study, (2) where is it found in nature, and (3) why is it found there. Without collections most taxonomic research cannot be conducted. Since the rigour of the scientific process is based on repeatability, the specimens used in research are preserved in museums to ensure that they are available for future reference and study.

As centralized repositories of reference material, the collections reduce the need for fieldwork in remote and/or poorly accessible regions, saving both time and money. Furthermore, museums liberate researchers from the time and expenses of maintaining all the specimens necessary for a functional reference collection. Given that unlike library books we cannot copy natural history specimens that were preserved, natural history collections are indeed unique locations for information. With more species becoming rare or extinct, such collections are often the only source of information for such species (Fig. 5), becoming frozen glimpses of a bygone past. For instance, it is known that during the last 600 years, 129 birds (or 1.3% of all known living bird species) have become extinct.

Fig. 2. Two of the type specimens of the Manchester Museum’s collection of tortoise beetles (Cassidinae). The Manchester Museum holds more than 22,000 type specimens, representing 8,000 species names.

The scientific value of a natural history collection is usually measured by the number of type specimens it contains (Fig. 2). A type specimen is a reference specimen selected by a scientist during the description of a new species. Type specimens serve as the primary and unique references for all known species names. They play a key role in stabilizing the use of species names. Museums also hold voucher specimens, which are examples of organisms collected during biodiversity surveys, taxonomic inventories and other research. These specimens are physical proof that species have been recorded from the studied site and identified accurately, and they are always available to be referred to or checked upon when/if necessary.

Fig. 3. The scientific value of a natural history specimen depends on the reliability of information written on its label; illustrated is a blister beetle.

Conservation and environmental studies

Conservation programmes, particularly those aimed at mapping priority areas for protection or conservation purposes, require a reliable knowledge of the distribution of species. Yet, for the vast majority of species known to science, most of the available information relating to them exists in the form of taxonomic collections. Sometimes such collections form the only source of data for particular species. Therefore, the most common way distribution information is collected is by examining labels of voucher specimen and databases in museums. These contain essential information about where (locality and habitat/host), when (an exact date) and by whom the specimens were collected (Fig. 3). Every natural history specimen with good data thus provides a physical snapshot of a species at a particular point in time and space. This highlights the need for correct and accurate labelling of museum specimens. A specimen without a label is usually worthless. The practice of utilizing the wide spectrum of information associated with specimens has been referred to as ‘museum ecology’.

Reference collections of voucher specimens and other taxonomic information on invasive species and pests can be used for their accurate identification and for understanding their current distribution and invasion history. In addition, they can be used for assessing the ecological impact of invaders and their potential public health threats. The famous example is the grey squirrel which was introduced to Britain from the USA in the 19th century, and as a result this species has caused native red squirrel populations to die out in most parts of England and Wales.

Natural history collections offer a unique perspective, providing data over a vast time span ranging from millions of years ago (in geological and palaeontological collections) to the present day. Specimens may have been collected over many decades and so record changing environmental conditions and their consequences. For instance, comparative genetic analysis of ancient museum specimens of brown bears with those from isolated populations today provides evidence of reduced levels of genetic diversity in the current populations, which negatively affects the survival potential of this species (Fig. 4).

Fig. 4. The brown bear became extinct from Britain by the 10th century, only museum specimens can help us to understand its history here.

In some circumstances museum specimens are the only record of species that are already extinct: e.g., Sloane’s Urania (Urania sloanus), one of the most spectacular day-flying moth species that was endemic to the island of Jamaica (Fig. 5). The moth was last reported in 1894 or 1895, but it possibly survived until at least 1908. Habitat loss, when Jamaica’s lowland rainforests were cleared and converted to agricultural land, may have caused its extinction. Most probably, this species disappeared due to the loss of one of its larval foodplants, as the Urania larvae fed exclusively on rainforest lianas belonging to the genus Omphalea.

Fig. 5. The Sloane’s Urania, an extinct species of which only three specimens are deposited in the Manchester Museum.

By examining museum specimens, it is also possible to analyze environmental impacts of climate change or a historical level of pesticide use. This is because historical collections provide baseline data against which modern observations can be compared in order to produce predictive models. For instance, an analysis of preserved bird specimens and their eggs (Fig. 6) can help to monitor the accumulation of toxins, such as mercury or DDT (a famous synthetic pesticide, the use of which is now banned), in the environment resulting from the impact of industrial processes. It has been shown that a marked decrease in eggshell thickness is coincident with the onset of the widespread use of DDT.

Fig. 6. The egg collection such as that of the Manchester Museum can help in the estimation of historical levels of toxic contamination in the environment.

Education and cultural value

Natural history museums are places where a visitor can have a unique experience of seeing authentic objects. Therefore, these museums play an important role in education through their exhibits and outreach programmes which use real specimens. Specimens are also used for illustrating natural history books, in which colourful plates are made on the basis of museum specimens (Fig. 7). Natural history specimens, especially beetles and butterflies, are regularly used by designers and artists who draw inspiration from their remarkable variety of forms, colours and patterns. Some natural history specimens or collections have their own historical and/or even high monetary value that makes them important items of the national heritage (Fig. 8). Overall, larger and more comprehensive natural history museum collections form better educational resources.

Fig. 7. The recent guide to the freshwater life of Britain contains at least 45 colourful plates of hundreds of insects illustrated from the Manchester Museum’s insect specimens.

Historic natural history collections are directly related to social history through their links to people and places. They are indeed a cultural phenomenon rather than dusty artefacts of professional science. The labels assigned to specimens and the documentation associated with them (e.g., information on the network of collectors, the distribution of collecting across the world, etc.) are commonly used in biographical and historical studies. Hence, natural history collections provide an outstanding and unique resource for a wide variety of client groups.

Fig. 8. Apollo butterflies are often restricted in distribution, many of them being threatened and red-listed.

Nowadays, opening cabinet doors and examining museum specimens kept there is not the only way of consulting natural history collections. All large natural history museums make their searchable collection databases and other collection-related information (i.e., images of type specimens) widely available on the Internet, so that collections can be searched and seen online. Such online access to networked data is especially important both for casual and professional users who, for various reason, may be unable to visit a particular museum. Nevertheless, whatever modern advanced technologies can offer us museum natural history specimens have been and always will be the only physical proof and irreplaceable primary documentation of life on Earth. This is what makes museum collections so valuable. Finally, nobody can extract DNA from an online image or test it for pesticide residues, but a physical specimen can provide a wealth of unexpected and inexhaustible information.

Further reading

Diamond J. & Evans E.M. 2007. Museums Teach Evolution – Evolution, 61-6: 1500-1506.

Krishalka, L. & Humphrey P.S. 2000. Can Natural History Museums Capture the Future? – BioScience, 50(7): 611-617. doi: http://dx.doi.org/10.1641/0006-3568(2000)050%5B0611:CNHMCT%5D2.0.CO;2

Mandrioli M. 2008. Insect collections and DNA analyses: how to manage collections? – Museum Management and Curatorship, 23(2): 193-199; doi: 10.1080/09647770802012375

 

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Taxonomic Research and Collection Care

When museum natural history collections are talked about, it is usually stressed upon how they are important for research (taxonomic, environmental and biodiversity, in particular), education and culture-related enquires (art, design, etc.) – e.g., see here. The following short video could also give you some ideas about the role of museum collections in taxonomic research (created by Jonathan Joseland, an undergraduate student at The University of Manchester, 2018).

However, much less is known about the importance of taxonomic research for collection care and development, particularly for the collections of such diverse groups as plants, molluscs, insects, crustaceans, and other arthropods. There are three main reasons why continuous taxonomic research on natural history collections is essential for their maintenance.

Fig. 1. A store box with undetermined specimens of ladybirds (Coccinellidae), one of some 300 store boxes with over 50,000 undetermined specimens of foreign beetles retained at the Manchester Museum. © The Manchester Museum

1. Naming objects

The first and indefeasible need for each natural history collection is the naming of its objects, which means assigning them to particular species. This can be done by mean of a scholarly taxonomic research only. Before an object has been named, it has no identity and hence no meanings and values can be accrued to it. As A.B. Gahan (1923: 73) put it, “objects without names cannot well be talked about or written about; without descriptions they cannot be identified and such knowledge as may have accumulated regarding them is sealed.” Thus, naming comes first. The Book of Genesis provides the first example of this endeavour, in which, by God’s will, Adam was tasked to name the animals in the Garden of Edem (Fig. 2).

Fig. 2. On the left: Adam naming the animals, the miniature from the medieval bestiary preserved at the St.-Petersburg Public Library, Russia (taken from Muratova, 1984: p. 72). On the right: the portrait of Carl Linnaeus, a Swedish scientists of 18th century who created the modern rules of practical taxonomy and nomenclature (taken from Harnesk, 2007: front cover design).

At present we can hardly rely upon Adam’s help any more. The burden of naming now lies on the shoulders of researchers – taxonomists – who name (= identify or describe as new) species in natural history collections, hence making their further use possible. Although museum life of a natural history specimen can precede its naming (e.g., via the act of acquisition, accession in museum registers, etc.), their ‘individualized life’ starts only after they have been named. Since a language does not contain names for every existing species, new ones are to be introduced when necessary. By conventional taxonomic practices, such names should be written in Latin, forming a kind of common vocabulary of scientific names. Whoever uses such names knows exactly what species they represent and are referred to.

Vernacular and folk names, even if they exist, cannot substitute for scientific names, as they are often misleading. For instance, the name ‘daddy-longlegs’ could be equally attributed to the craneflies (families Tipulidae, Limoniidae, etc.), harvestmen (order Opiliones) or the cellar spiders (family Pholcidae). Thus, indeed, scientific names are unique identifier/designators of the species to which they were attached. In order to gain them, natural history specimens are to be researched by a specialist.

2. Keeping collections updated with modern names

Fig. 3. Example of the recently recurated collection of British micro-Lepidoptera, with all taxonomic names being revised and updated according to the latest published catalogue. © The Manchester Museum

Taxonomy is a dynamic scientific discipline. The status and validity of species names, especially in poorly studied groups, are constantly improved and updated. Therefore, identifications and names used in any natural history collections are to be regularly revisited and revised as well. Such work can be done only by specialists (both professional and amateur experts). This is why collections-based taxonomic research is required to maintain an updated nomenclature and documentation of any natural history collection, keeping it as a first-rate intellectual resource for potential users. Collections themselves can be seen as a giant research tool; the quality of how this tool is operated is crucial. Without taxonomic research, natural history collections are under threat of becoming dusty attics of the academic world, with no obvious reasons for museums to house them. As Lemieux (1981: p. 57) put it, “if collections are the base of the museum, research is its soul”.

3. Increasing the scientific value of collections

Fig. 4. Examples of holotype specimens of recently described cockroach species from Indian, based on the collections acquired by the Manchester Museum in 1950s. © The Manchester Museum

One of the most important criteria by which natural history collections are assessed is a number of type specimens, or types. The act of naming (see above) is conducted and fixed via a description, accounting for the relevant published text(s) and figure(s), in order to arguably introduce a new species name. Any description should have a permanent reference to museum voucher specimen(s) used for it. Such specimens are called name-bearing types (holotypes, paratypes, etc.), also known as rigid designators of scientific names. Original descriptions of new scientific names are always documented by types. A number of the types (especially holotypes) is one of the best indicators of a scientific quality of natural history collections; the more types, the better. For instance, the Manchester Museum’s Entomology Department holds over 12,000 types, representing some 3,000 scientific names of insects, spiders and some other organisms, which makes it one of the most important entomological depositories in the UK.

The naming is always resulted from a taxonomic research. This research acts in its own right, requires highly professional special skills and cannot be replaced with anything else.

Today, one of the challenges many British museums (especially regional and council ones) face is the lack of in-house taxonomic expertise. Collections-based taxonomic research does not emerge as the core strength of contemporary museum policies, with entertainment and education being likely to be seen as priorities. Taxonomy does not carry the same appeal to the popular mind as does the science fiction around dinosaurs. In the UK today, research is widely seen as luxury by museums rather than an essential part of their role (Cross & Wilkinson, 2007). It means that such museums are hardly able to maintain their collections updated and to interpret them. This is very serious issue which will be considered in due details in one of the following blog post.

References and further reading

Appleton, J. 2001. Museum for the People. In: Appleton, J. (ed.), Museum for the People. London: Institute of Ideas, pp. 14-26.

Cross, S. & Wilkinson, H. 2007. Making collections effective. London: Museum Association. 30pp.

Kemp C. 2015. The endangered dead. Nature, 518: 292-294.

Lemieux, L. 1981. Museums of natural history and their social context. Pp. 55-58. In: The World’s Heritage, the museum’s responsibilities. Proceedings of the 12th General Conference and 13th General Assembly of the International Council of Museums. The ICM.

 

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