Chiropteran taxa (Brain 1998).
Donovan Reginald Rosevear (1900–1986) pioneered the development of the forestry industry in Nigeria from 1924 to 1954. His enthusiastic studies of the West African fauna included significant collections of mammals. After his formal retirement, he completed three monographs on West African mammals over the subsequent 20 years in research at the British Museum (Keay 1986). These included a significant, lasting contribution in The Bats of West Africa (Rosevear 1965).
Reay Henry Noble Smithers (1907–1987), naturalist, falconer, editor, conservationist and mammalogist (among many professions), began his career as a chemist until joining the South African Museum in 1933; he transferred to the fledgling organisation of the then Museums of Southern Rhodesia in 1947. Besides his founding of four major museums in Zimbabwe, Reay both undertook and facilitated comprehensive natural history surveys across south-central Africa, notably of the mammals of Botswana (Smithers 1971). Among many selfless contributions were lasting inputs into conservation, notably to pioneering legislation of the National Parks and Wildlife Act of Zimbabwe. Perhaps the greatest monument to his legendary excellence in museology and commitment to science resides in the largest collection of mammals in the southern hemisphere at Bulawayos' Natural History Museum. His magnum opus, the Mammals of the Southern African Subregion (Smithers 1983), collated a wealth of his original data on the regions' mammal fauna, including bats (Raath 1988).
Michael Rogers Oldfield Thomas (1858–1929) devoted virtually all his lifes' attentions to the mammal collection at the British Museum (Natural History) – from 1878 until after his official retirement in 1924. In this period the collection grew exponentially through at least 1 million specimen accessions. His lifes' total of 1,090 scientific publications included the scientific descriptions of some 2,090 new taxa of mammals from across the world; Thomas named many Afrotropical bats (Hill 1990). This immense taxonomic legacy endures, alongside the mammal collection in the British Museum, as a significant foundation of scientific knowledge in the twenty-first century. This portrait (circa 1914) was painted by John Ernest Breun.
THE VALUE OF SPECIMENS
Many of the known bat records – vouched for by preserved specimens of bats – have been published. For example, the first article devoted exclusively to the bats of Zimbabwe (Harrison 1959) summarised new material added to the museum collections of the country. In the main, these older articles were published in museum journals that are relatively hard to obtain, or the data reside in monographs long out of print (e.g. Ansell 1978, Smithers and Wilson 1979). Existing taxonomic uncertainties often undermine the credibility of these historical data, but fortunately, nearly all the originally reported specimens still exist – in museum collections. Continued preservation of each specimen maintains a node of original data, whose persistence over time acts to anchor the interconnecting web of knowledge. By remaining available for independent re-examinations, each of these specimens maintains the veracity of scientific knowledge. An excellent example is the recent revision of Afrotropical slit-faced bats, Nycteris, using specimens (Demos et al. 2019a). The value of natural history collections preserved in museums increases with time, but they are regrettably too often neglected, even within the biological community (Cotterill 1995a, 1999, 2002c, 2016, Cotterill and Foissner 2010, Gippoliti 2018).
The loss of any one of these specimens, let alone an entire collection, has severe consequences. A pertinent example is the fire that destroyed a wealth of unique zoological specimens at the Museu Bocage, Lisbon, in March 1978. Its depredations on scientific knowledge included the destruction of all the type material of the Chiroptera described by J. V. Barboza du Bocage and A. F. de Seabra from Angola (see Palmeirim et al. 1979, Bergmans 1990). In this book we repeatedly refer to the problems these losses will continue to cause in bat taxonomy for many taxa.
These specimens are the fundamental sources of scientific data to support efforts to conserve biodiversity, as explicitly recognised by the 1992 Convention on Biological Diversity. The distribution maps in this book are based entirely on museum specimens representing 6,344 unique locality-species records (Figure 11), 73% of which have been personally checked by at least one of the co-authors (marked as red dots on the map in Figure 11). These collections provide unique references for the scientific identification of new specimens, as they include those type specimens that vouch for the formal description of species (Cotterill 1995a, b, 1999, 2002c, Cotterill and Dangerfield 1997, Cotterill and Foissner 2010, Gippoliti 2018, Taylor et al. 2019a).
Figure 5. (a) The study skins and skull collection of small mammals in Bulawayo is estimated at over 50,000 specimens, including invaluable series of bats. A series of Mops midas is arrayed in the foreground. (b) A small part of the wet collection of mammals, Natural History Museum of Zimbabwe, Bulawayo (© F. P. D. Cotterill).
Discovery of new species of bats continues today in many biodiversity hotspots, including parts of Africa (e.g. Taylor et al. 2012, 2018a, 2019a, Monadjem et al. 2013a, b, Kerbis Peterhans et al. 2013, Decher et al. 2015). This is in part due to new collections from remote areas, as well as sophisticated new taxonomic tools, which include echolocation studies and systematic revisions that incorporate molecular evidence (DNA sequences). As with any serious biogeographical or taxonomic work, the direct study of specimens is essential to the scientific credibility of all such research.
CHIROPTERA COLLECTIONS
The devotion of bat collectors in southern Africa has led to the establishment of several major Chiroptera collections, housed in the following southern African museums: the Amathole Museum (previously the Kaffrarian Museum, King Williams' Town), the Durban Natural Science Museum, the National Museum (Bloemfontein), the South African Museum (Cape Town), the Ditsong National Museum of Natural History (formerly the Transvaal Museum, Pretoria), the Natural History Museum of Zimbabwe (Bulawayo), and the Namibian National Museum (Windhoek). There are smaller mammal collections in Angola (Lubango and Dundo), Zambia (Livingstone), Malawi (Blantyre), Mozambique (Maputo), and more recently in the E. O. Wilson Laboratory in Gorongosa National Park (Chitengo, Mozambique) and at the University of Eswatini (Kwaluseni, Eswatini). These important resources, located within Africa, complement the major natural history museums in Europe and North America (see the List of Specimens).
Figure 6. Senior Technical Officer Alick Ndlovu, Natural History Museum of Zimbabwe (NMZB), collating field data on bat specimens in western Zambia in November 1998. Alick Ndlovu deserves special credit for his sterling efforts in re-cataloguing the entire Mammal Collection (NMZB), which includes nearly 9,000 specimens of Chiroptera (© F. P. D. Cotterill).
Figure 7. (a) Prototype of a bicycle trap placed under a crevice roost ~100 m up a granite precipice; the trap is suspended from pulleys secured on the inselberg summit (Cotterill and Fergusson 1993). (b) Three species of free-tailed bats captured from their crevice roost using a bicycle trap near Chikupu Caves, including Chaerephon ansorgei and C. bivittatus, with a Tadarida fulminans in the foreground (Murigabveni, northeast Zimbabwe; © F. P. D. Cotterill).