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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.

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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.

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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).

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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.

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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.

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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.

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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.

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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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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.

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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).

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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

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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

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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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With over two and a half million specimens deposited in the Manchester Museum’s Entomology Department, ongoing re-curating and documenting these collections constitute a significant part of the wok undertaken by the Curator and his colleagues. Such huge insect collections also present lots of opportunities for students to volunteer in the Museum and to help out museum staff with the documentation and re-organisation of its insect collections.

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Louis Nicolls extracting information from data labels of the Manchester Museum’s mantis collection.

Below is a short report prepared by one of the Museum’s volunteers, Louis Nicolls (see above), a second-year undergraduate student from the Manchester Metropolitan University whose passion is mantises (Mantodea):

“I am currently working on the mantis collection at the Manchester Museum. The work I’m tasked with consists of the extraction of any information from the museum’s archives, collection and annual reports with the aim to collate it all into one succinct report describing the history of the mantis collection, including the first accessions and the collectors who’ve donated the specimens. The report will also provide statistics on the collection, stating its size, the number of species and the percentage of the world’s species we have at the Museum. It will highlight interesting species and any type specimens. Behind the scenes, I will also be updating all the relevant information within the museum database on locality, date and collector information.

This project is exciting because I have been learning a great deal about praying mantises. it’s allowing me to better understand their distribution, taxonomy and history from a systematic context. The project is also providing excellent experience with museum entomological collections, pushing me to learn how they are organised and run as well as how fundamentally important they are within the sciences but also to the general public. The nature of the work is a balanced melding of historical research and scientific study making it stimulating and informative as it pushes me to use initiative and apply myself in ways I wouldn’t normally do so.”

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Example of the drawer with mantises from the collection of Manchester Museum.

Further reading:

Logunov, D.V. 2010. The Manchester Museum’s Entomology Collections. – Antenna, 34(4): 163-167.

Logunov, D.V. & N. Merriman (eds). 2012. The Manchester Museum: Window to the World. London: Third Millenium.

Logunov, D.V. 2012. Why do museums have natural history collections? – Feedback, the ASAB education newsletter, 52: 12-15.

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Fig. 00. Young specimens of Migratory Locust (Locusta migratoria), NE Kazakhstan. The photo demonstrates distinct colour differences between solitary (left), intermediate (middle) and gregarious (right) forms. © Victor V. Glupov (Novosibirsk, Russia).

It seems that apart from Locust (and perhaps fleas) there are no other insects which could have been so destructive to human affairs and civilizations. When conditions are favourable, vast migrating swarms of Locusts can appear as a cloud that darkens the sky and rapidly devour all plant material on their way, from field crops to the foliage on trees. So great is their apocalyptic quality in human minds that, since the time of the Pharaohs, Locusts have been seen as a symbol of destruction – the wrath of God or a sign of cosmic disorder.

At first glance, Locusts look like large, short-horned and harmless grasshoppers, but their behaviour is different. Unlike grasshoppers, when Locusts are present in large numbers they tend to crowd together, forming vast swarms that can migrate long distances and cause catastrophic plagues. Large swarms can invade an area of Africa and Asia that extends across 57 countries and covers more than 20% of the land surface of the Earth (Fig. 1).

A single swarm may contain many million individuals, with an overall mass of several tonnes. Since these insects eat approximately their own mass of vegetation daily, they cause immense destruction of crops and pastures. For instance, 2.5 square kilometre’s worth of locusts – 100 to 200 million individuals – can consume 220 to 270 tonnes of food, which is enough to feed 200,000 people. In a single day, an average swarm can eat the same quantity of food as 2,500 people.

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Fig. 1. The invasion area of the Desert Locust (Schistocerca gregaria) and areas in which outbreaks are known to have occurred (from Logunov, 2006).

The apocalyptic quality of Locusts in human minds seemed to be the reason why their grotesque figures – gargoyles – were sometimes carved into the architecture of churches and monasteries (Fig. 2), perhaps creating a symbolic representation of hell. Furthermore, of some 98 bug species mentioned in the Revised English Bible, the Locust is referred to at least 31 times (see also here). For instance, “…When morning came, the east wind had brought the locusts. …They devoured all the vegetation and all the fruit of the trees that the hail had spread.” – The Bible, Exodus (10: 13–15). Indeed, it could be an apocalypse for those people who observed Locust swarms in action.

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Fig. 2. A Locust gargoyle in the two-storey cloister of the Jerónimos Monastery (16th century, Lisbon, Portugal). © Dmitri V. Logunov (Manchester, UK).

Therefore, it is hardly surprising that ecclesiastic institutions of early medieval Christian Europe portrayed Locusts as chimeras, demonic and malevolent creatures (Fig. 3, on the left). Such visualization reflected the prevailing theological conceptions of Locust as an instrument of divine vengeance. Its more or less human-like head reflected the mind needed to separate sinners from pious people; the strong wings were needed to fly over humans in order to administer the justice; the scorpion-like tail was the main tool of chastise; etc. Such depiction of the Locust is a striking example of the distortion of human perception induced by the symbolic view of reality, which was introduced by theologians. No doubts, even in the sixteen century people knew very well how real insects look like (Fig. 3, on the right).

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Fig. 3. Two contrast depictions of Locusts. On the left: A section of the Monogrammist HW, “Natuerliche Contrafeyhing…”, dated 1556, a diabolic depicting of the locust (Zürich; modified from Ritterbush, 1969: fig. 2). – On the right: A section of the plate from “Archetypica studiaque patris Georgii Hoefnagelii”, dated 1592, a realistic depiction of the locust; from the archives of the Oxford University Museum of Natural History (from Smith, 1986: plate 13).

Despite some Locusts are great pests in many parts of the world, human attitude towards them is not particularly cruel. In India, when a swarm of Bombay Locusts (Nomadacris succincta) comes, people just try to scare them away by lighting fires, beating brass pots, and ringing the temple bell. In Uttar Pradesh, people catch one Locust, decorate its heard with a spot of red lead, salaam to it, and let it go; thereupon people believe that it will immediately depart with all its companions.

There is at least one benefit of having locusts in swarms: they can be harvested and used as food (Fig. 4; see also here). The Arabs boil them with salt, and then add a little oil or butter; sometimes they toast them by the fire before eating them. In Madagascar, there is a common saying: “One needs to waken early in the morning to catch grasshoppers”. About 80 grasshopper/locust species are consumed worldwide. In Morocco, even the price of provision falls when the Locusts appear. The main problem with consuming Locusts is that due to their status of agricultural pests they may be sprayed with insecticides in governmental control programmes, which makes them a polluted food.

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Fig. 4. Locusts are ready for consumption. © J. Princess.

In some other cultures, for instance, those of Native Americans, the relationships between Locust-like insects and man were less dramatic than in medieval Europe, although not fully friendly. The following animation ‘Banquet’ is loosely based on an old folktale by Yaqui people from northern Mexico. It is about a Grasshopper and a Cricket that attended an Indian banquet. They ate and drank with the Chief but behaved badly, so that Yaqui people did not want them coming back.

Created by Eva Akesson, a BA Animation student of the Manchester School of Art at the Manchester Metropolitan University in 2016. Music composed by Peter Byrom-Smith and performed by the Guild Hall Collective, conducted by Rod Skipp.

Control of Locusts is a challenge. Some says that no attempt to control locusts or bring down the swarm has ever succeeded – in each case the plague disappeared only when nature had run its course. Globally, the costs of combating this plague were colossal, over 300 million US$. It is believed that recent plagues happened mainly due to the decline of co-operation between neighbouring countries. Survey and control operations often have to be carried out in important breeding areas in which access is severely restricted due to civil conflicts and general insecurity (some regions of Algeria, Somalia, Yemen, Sudan and others). Thus, the true key issues of locust control now are not the lack of scientific knowledge or technical means, but a problem of socio-political organization which cannot be controlled by scientists. Unless this basic issue is resolved, alas, humans will always be at the mercy of nature when it comes to dealing with locust plagues.

 Further reading

Chapman, R.F. 1976. A Biology of Locusts, Studies in Biology no. 71, Edward Arnold, Great Britain.

Logunov, D.V. 2006. Locusts: God’s wrath or revelation. Biological Sciences Review, 19(1): 6-9.

Kritsky G. & Cherry R. 2000. Insect Mythology. Writer Club Press, San Jose, New York, Lincoln, Shanghai.

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Many of the visitors to the Manchester Museum’s Entomology store are researchers, studying various aspects of insect diversity, taxonomy and even physical properties of their colour. A group of researchers from the New Castle University (UK) is interested in what could be a real colour of butterflies and moths seen as if through the eyes of their predators, birds in particular. Here is a brief report provided by Matthew Wheelwright (Fig. 1), a postgraduate student who is involved in this research project:

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Fig. 1. Matthew Wheelwright, a postgraduate student from the New Castle University (on the left) and Phillip Rispin, a curatorial assistant from the Manchester Museum (on the right), are sorting out lepidopteran specimens for scanning.

Colour is vitally important for many aspects of insect lives. It can help them to control their body temperature, or allow them to be recognised by members of their own species. The right body/wing colour can allow insects to blend into their environment in order to hide from predators. Another way in which colour can be used to escape predation is through giving a clear message to their potential predators that they are toxic, not edible or unpleasant tasting and should therefore be avoided. Such insects are usually brightly coloured, with a mixture of yellow/orange and black stripes and spots on their wings. This phenomenon is known as warning coloration (=aposematism). Some other species which occur in the same areas can also benefit from these warning signals by evolving to look like these not edible species; this phenomenon is known as mimicry.

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Fig. 2. Butterflies and moths from the collection of the Manchester Museum sorted out for scanning by means of a hyperspectral camera.

The purpose of our study is two-fold. Firstly we want to find out what makes a good pattern of warning coloration and secondly to discover how closely a mimic must resemble a model having warning coloration (=aposematic model) in order to deceive predators into thinking that they are the same species. In order to do this, we need to know how these patterns look to predators (many of which have different visual systems to humans). We therefore take pictures of specimens from various collections from across the globe, including the entomology collection at the Manchester Museum (Fig. 2), using a hyperspectral camera (Fig. 3). This camera allows us to look at the exact colour spectrum of the specimens, including the amount of Ultraviolet (UV) reflected by them. The latter aspect is very important, as many predators, such as birds, can see in UV.

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Fig. 3 A hyperspectral camera at work, scanning the Black Witch Moth (Ascalapha odorata) from the collection of the Manchester Museum.

We then used models of predator visual systems to quantitatively compare the colour and pattern of aposematic species to non-aposematic species and the patterns of mimics and models to predict how the predators could perceive them and therefore react to them. In other words, we try to see butterflies and moths through the eyes of insect predators and hope to find out whether insects that look aposematic to us (or their mimics) are seen in the same way by their predators.

Two images of the Orange Sulphur (Colias eurytheme) given below (Fig. 4) show how the butterfly appears to humans (on the left) and to a bird (on the right). Orange Sulphur looks iridescent under the UV, and the false colour image on the left contains the purple representing where the UV is the brightest and seen to birds. The image was kindly created for us by Olivier Penacchio of the University of St. Andrews.

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Fig. 4. Two views of Orange Sulphur (Colias eurytheme): left – as seen by a human; right – as could be seen by a bird (contains the purple representing where the UV is the brightest). © Olivier Penacchio

Such research project would be impossible without access to museum specimens from large entomological collections such as that of the Manchester Museum. So we would like to take this opportunity to thank Dr Dmitri Logunov and Phil Rispin for their assistance and generosity with the loan of some specimens.

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Fig. 1. The specimen of Euoniticellus intermedius (Reiche, 1849) from Honduras in the collection of the Manchester Museum. © Roisin Stanbrook.

In November 2017, the Manchester Museum acquired a specimen of a very interesting dung beetle – Euoniticellus intermedius (Reiche, 1849) (see Fig. 1) – collected from Honduras by Roisin Stanbrook, a young researcher from the Metropolitan University of Manchester who studies the ecology of dung beetles in Central Africa (see here for her interview). In Honduras, Roisin was running a field course for a group of British students, when she came across this beetle which she was familiar with from her fieldwork in Kenya. What a surprise! Below is a brief account of how this dung beetle species appeared in Central America.

E. intermedius is also known as the Intermediate Sandy Dung Beetle. It is a medium sized (6.5-9.5 cm long) species of the burrowing dung beetles that build brood chambers in the soil beneath a dung pat and supply them with dung as food for their larvae. Although this beetle is native to Africa, now it has a worldwide (=cosmopolitan) distribution because the species was intentionally introduced to many countries such as Australia, New Caledonia, Hawaii, Puerto Rico and the USA, as a biological control to decrease the dung accumulation caused by cattle and the proliferation of pest flies.

Following its introduction to the USA (in California apparently in 1978, in Texas in 1979, and in Georgia in 1984), E. intermedius started a rapid range expansion across the south of the USA, up to Florida, and Central America, with an estimated speed of about 50 km or more per year. In 1992, it was first recorded in Mexico (the site Mapimí), then it reached Guatemala in 2002, Nicaragua in 2007 and Costa Rica in 2008; in 2015, the beetle was already recorded from the border of Panama (see Maps below).

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Maps. A – Dispersal of Euoniticellus intermedius in Mexico after its introduction in the USA (after de Oca & Halffter, 1998). B – Further dispersal of E. intermedius from southern Mexico across the Isthmus of Panama (after Solis et al., 2015).

 

The beetle has been particularly successful at colonizing arid zones, where the number of native burrowing dung beetles was rather low. For instance, at some places in Mexico, 96% of the individuals (and a great proportion of biomass) corresponded to two invasive dung beetles: E. intermedius and the Gazelle Scarab – Digitonthophagus gazella (Fabricius, 1787), another widely introduced species of dung beetles (see here for further information about it).

But why has the Intermediate Sandy Dung Beetle been so successful in colonizing Americas? There are two main reasons. First, this species has certain biological properties that help its rapid expansion: (1) it is a highly prolific species that can have two or more broods of offspring per year; (2) it is an eurytopic species that can live in a wide variety of habitats and tolerate a wide range of environmental conditions; and (3) it has a preference for bovine dung, which is both very abundant in cattle-farmed areas and nutritionally rich, but yet poorly/not utilized by native Central American species.

Second, quite favourable ecological conditions for E. intermedius (and for D. gazella) have been created by the human activity in Central America: viz., (1) deforestation leading to the creation of open, sunny and dry habitats (=pastures) to which this African species is well-adapted; (2) increase in cattle breeding resulted in the production of excessive amounts of dung (=food resource for the beetle); and (3) the inability of native dung beetles to properly utilize cattle dung, which actually means that there was no competition with native species for this food resource.

Although the ecological impact of E. intermedius on native dung beetles is poorly understood yet, those from the guild of burrowing (=paracoprid) dung beetles are to be affected for sure. Soon we’ll be able to see if this beetle is able to colonize South America and what its presence in the areas already invaded could do to the native biota.

Here and here you can find further information about E. intermedius.

Further reading:

Oca de, E.M. & Halffter, G. (1998) Invasion of Mexico by two dung beetles previously introduced into the United States.- Studies on Neotropical Fauna and Environment, 33(1): 37-45; http://dx.doi.org/10.1076/snfe.33.1.37.2174

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Copris_lunaris

Nesting by the Horned Dung Beetle (Copris lunaris): 1 – Initial stage, male (left) and female (right) working the ‘dung cake’; 2 – Female alone, making brood-balls of the ‘cake’ for laying eggs. Illustration by V.A. Timokhanov (Almaty, Kazakhstan).

Waste disposal is a growing problem for any industrialized nation. The UK alone generates about 100 million tonnes of waste each year, the majority of which is still being disposed of through landfill. The present story is about dung beetles or scarabs (family Scarabaeidae) that are involved in processing and decomposing dung.

On average, about 40% of the food intake of mammals is either excreted as urine or passed out of the body as faeces. This waste is decomposed and returned to the soil by insects that use dung as food for themselves and for their larvae, thereby preventing it from building up. How this is accomplished is best known for cattle dung.

A cow’s fresh dung pat is colonized by a succession of dung-breeding insects, numbering several dozen species and often exceeding 1000 individual insects. A total of 275 species has been reported to occur in cattle dung in Britain. The majority of them are dung beetles that feed directly on dung. There are three main ecological groups of dung beetles. First, small-sized beetles (Aphodius species) usually feed in the main dung mass. Others, like the horned dung beetle, dig burrows beneath the pat and pack pieces of dung into them for feeding their larvae (see figure above). The third group includes beetles that make spherical dung balls, roll them away and bury them intact in shallow burrows. The Sacred Scarab is the most famous of the rollers. As well as dung beetles, the pat is colonized by dung-feeding fly maggots, predatory beetles which feed on eggs and larvae of other insects, small parasitic wasps, fungus-eating insects and mites, etc. At the advanced stage of degradation, soil invertebrates, including earthworms, begin to move into the dung pat. The natural rate of dung degradation depends on temperature, humidity, habitat and season of deposition. In Britain, the complete natural disappearance of a dung pat is achieved in two to three months.

Sacred_Scarab_Stockholm

Sculpture of the Sacred Scarab in the Natural History Museum in Stokholm, Sweden. © Dmitri Logunov, Manchester Museum.

It is known that each cow produces an average of 12 dung pats per day, or over 9000 kg of solid waste per year. It is estimated that each year approximately 200 million tonnes of waste are produced by livestock in England and Wales, and about 900 million tonnes in the USA. About third of this is recycled by dung beetles. In the USA alone, the annual economic value of this service is at least $380 million.

Unfortunately, the activity of dung beetles is severely disrupted by current agricultural practices, such as the treatment of livestock with persistent anti-helminth drugs given to kill parasitic worms or helminths. Residues of these drugs can persist in the dung and are lethal to the beetles. As a result, the dung pats of animals treated with anti-helminthes remain biologically undegraded for months, fouling available grazing area. If left unprocessed, livestock wastes may present a health risk to humans, because they can contain some pathogenic microorganisms.

By recycling the nutrients locked up in dead organic materials such as dung, insects make these nutrients available to new life. As recyclers, they do an indispensable job for our planet. Without organisms breaking down dead organic materials and recycling nutrients in the wild, as well as in gardens and on farms, the planet would soon be piled deep with the waste products of its inhabitants, and potential spread of diseases would be unavoidable. Whether we like it or not, our own existence directly depends on insects and their ecological services. As M. Telfer (2004) put it: “Not everyone welcomes having ‘creepy-crawlies’ around but we should be grateful for what they do.”

In the following video, our special guest, Ms Roisin Stanbrook from the Manchester Metropolitan University, is taking about the ecological role of dung beetles in Kenya.

The presented story is based on: Logunov D.V. 2010. Nature’s recycling squad. Biological Sciences Review, 22(3): 22-25.

Further reading:

Berenbaum, M.R. (1995). Bugs in the system. Insects and their impact on human affairs. Helix Books.

Waldbauer, G. (2003). What good are bugs? Cambridge-London: Harvard University Press.

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