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Mammalia

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Volume 82, Issue 1

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An SEM image reference guide to hairs of 12 species of large African mammals

Shelby Wade
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  • Department of Biology, Western Kentucky University, 1906 College Heights Boulevard, Bowling Green, KY 42101, USA
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/ Michael Stokes
  • Department of Biology, Western Kentucky University, 1906 College Heights Boulevard, Bowling Green, KY 42101, USA
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/ Craig Spencer
Published Online: 2017-02-21 | DOI: https://doi.org/10.1515/mammalia-2016-0053

Abstract

We developed a pictorial atlas of 52 scanning electron microscope (SEM) images of hairs found on 12 mammalian game species commonly found in the South African lowveld. Guard hairs were taken from the dorsoscapular, scapular, sternal, or axillary regions of each animal; and bristle hairs, if present, were collected from the manes of animals of each species. These images, along with other diagnostic features of hairs, can be used as an identification system. Such a system is useful for ecological studies where identifying animal remains is necessary.

Keywords: African wildlife; cuticle scale patterns; hair; pictorial atlas; SEM

Introduction

Morphological features of mammalian hairs have proven to be useful in a variety of academic and biological studies, including predator diet analyses, conservation management, forensic studies, medical uses, and even archaeological studies (Deedrick and Koch 2004, Wentworth et al. 2011, Braczkowski et al. 2012, Mbizah et al. 2012, Verma and Joshi 2012, Davidson et al. 2013, Taru and Backwell 2013, 2014). Hair is made mostly of keratin, which is more resistant to decay and digestive alteration than other mammalian tissues, such as dentin or bone (Deedrick and Koch 2004, Backwell et al. 2009, Mansilla et al. 2011, Taru and Backwell 2013).

Previous catalogs have used several terms to describe the different common cuticular scale patterns. These terms include imbricate, mosaic, chevron, coronal, and petal-like or spinous (Homan and Genoways 1978, Keogh 1983, Deedrick and Koch 2004). In addition to the shape of the scales, distances between two adjacent scale margins are often used as descriptors and identification markers, and the scale margins can be described as smooth, crenate, or rippled (illustrated in Keogh 1983).

In several studies, cuticular scale patterns of hairs were used to aid in the process of species identification (Johnson and Hansen 1979, Rosas-Rosas et al. 2003, Manfredi et al. 2004, Breuer 2005, Ott et al. 2006, Wentworth et al. 2011, Braczkowski et al. 2012, Mbizah et al. 2012, Davidson et al. 2013). This is often accomplished by creating a scale imprint by mounting a hair on a slide using clear nail polish or a gelatin and allowing it to dry (Homan and Genoways 1978, Keogh 1983, Mizutani 1999, Ott et al. 2006, Wentworth et al. 2011, Mbizah et al. 2012). Once dry, the hair is removed and the remaining mold is then observed under a light microscope. However, with a scanning electron microscope (SEM), scales can be observed on the hair. The SEM provides higher contrast images of the cuticle scale patterns, yielding better resolution than light microscopes (Sahajpal and Goyal 2009), revealing different scale shapes, scale margin patterns, and accurate distances between scales.

Short (1978) and Taru and Backwell (2014) argued that scale patterns are not enough to accurately identify mammalian species to a taxonomic level finer than genus. The purpose of this catalog is not to address this point, but rather to provide a clear reference system for those who are looking to use scale patterns to aid in the identification of African fauna from hair samples.

Species studied

We photographed guard hairs or bristle hairs from 12 species (Table 1). Classifications follow Wilson and Reeder (2005).

Table 1:

Hairs from these species were imaged with the SEM.

Materials and methods

Most hairs were collected from specimens in a taxidermy office located in Phalaborwa, Limpopo Province, South Africa. Lion hairs were collected from the Louisville Zoo, located in Louisville, KY, USA. Gemsbok, lion, and leopard hairs were donated by the Thomas M. Baker collection of Bowling Green, KY, USA. Most guard hairs were collected from the dorsocapular, scapular, chest, or axillary region of each animal, as was done in previous studies (Homan and Genoways 1978, Short 1978, Keogh 1983, Hess et al. 1985, Seiler 2010). If bristle hairs were present, they were collected as well. The bristle hairs were always taken from the mane of the species. Dark and light colored leopard hairs were collected from the lower left flank, and gemsbok guard hairs were collected from the sternal region. Lion hairs were collected from lion feces gathered by the Louisville Zoo in Louisville, KY, USA, and from the axillary region and mane of a taxidermic specimen from the Thomas M. Baker collection of Bowling Green, KY, USA.

Hair shafts were soaked in 91% isopropyl alcohol for about 1 h for cleaning, and then soaked in distilled water for 3–5 min to rinse. After air-drying, they were prepared for observation under a SEM. They were mounted onto stubs using very smooth tabs (Cat #16084-20, Ted Pella) and sputter-coated with gold-palladium alloy (60% gold, 40% palladium) for 3 min. The stub was then turned 180° and again sputter-coated with the gold-palladium alloy. Whole hairs were mounted; in some cases long hairs had to be mounted in sections to fit on the stubs.

Samples were observed using a JEOL JSM-6510LV SEM at 10 kV and 500× magnification (unless otherwise specified) and photographed in three different locations – the proximal, medial, and distal regions.These settings gave the best resolution with the least amount of contrast on the edges of hairs. The same magnification was used for most hairs to give a reference for size differences among hairs and among different regions of the same hair. If more detail was needed, or if the hair was too big for the frame, the magnification was altered. Two hairs from each species and type of hair (i.e. guard or bristle) were observed with the SEM to ensure scale patterns were consistent before imaging.

Results

This pictorial atlas displays the cuticular scale patterns of 18 hairs (Figures 118) found on the pelage of 12 mammalian game species commonly found in the South African lowveld.

Guard hair of impala (Aepyceros melampus).
Figure 1:

Guard hair of impala (Aepyceros melampus).

Guard hair of impala (Aepyceros melampus).
Figure 2:

Guard hair of impala (Aepyceros melampus).

Guard hair of blue wildebeest (Connochaetes taurinus).
Figure 3:

Guard hair of blue wildebeest (Connochaetes taurinus).

Guard hair of waterbuck (Kobus ellipsiprymnus).
Figure 4:

Guard hair of waterbuck (Kobus ellipsiprymnus).

Guard hair of gemsbok (Oryx gazella).
Figure 5:

Guard hair of gemsbok (Oryx gazella).

Guard hair of steenbok (Raphicerus campestris).
Figure 6:

Guard hair of steenbok (Raphicerus campestris).

Guard hair of African buffalo (Syncerus caffer).
Figure 7:

Guard hair of African buffalo (Syncerus caffer).

Guard hair of male nyala (Tragelaphus angasii).
Figure 8:

Guard hair of male nyala (Tragelaphus angasii).

Bristle hair of male nyala (Tragelaphus angasii).
Figure 9:

Bristle hair of male nyala (Tragelaphus angasii).

Guard hair of giraffe (Giraffa camelopardalis).
Figure 10:

Guard hair of giraffe (Giraffa camelopardalis).

Bristle hair of giraffe (Giraffa camelopardalis).
Figure 11:

Bristle hair of giraffe (Giraffa camelopardalis).

Guard hair of lion (Panthera leo).
Figure 12:

Guard hair of lion (Panthera leo).

Bristle hair of lion (Panthera leo).
Figure 13:

Bristle hair of lion (Panthera leo).

Guard hair of leopard (Panthera pardus) light.
Figure 14:

Guard hair of leopard (Panthera pardus) light.

Guard hair of leopard (Panthera pardus) dark.
Figure 15:

Guard hair of leopard (Panthera pardus) dark.

Guard hair of spotted hyaena (Crocuta crocuta).
Figure 16:

Guard hair of spotted hyaena (Crocuta crocuta).

Guard hair of Burchell’s zebra (Equus burchellii).
Figure 17:

Guard hair of Burchell’s zebra (Equus burchellii).

Bristle hair of Burchell’s zebra (Equus burchellii).
Figure 18:

Bristle hair of Burchell’s zebra (Equus burchellii).

Discussion

We have presented the cuticular scale patterns of hairs from 12 mammalian species commonly found in the South African lowveld. In most cases, the process of Seiler (2010) was followed, and the three regions of hair shafts (proximal, medial, and distal) were photographed to display changes in the scale pattern along the length of the hair. These photographs support the conclusions of other studies stating that viewing hairs under an SEM is beneficial by contributing higher resolution and clarity of scale patterns than light microscopy (Sahajpal and Goyal 2009, Seiler 2010).

The samples of nyala bristle hair and Burchell’s zebra guard hair had damage to the hair shafts that destroyed the cuticle. In these cases, damaged regions of the hairs could not be photographed. Seiler (2010) also noted damaged, unrecognizable cuticular patterns in a number of her hair samples. She contributed this damage to museum storage. Keogh (1983), however, records that hairs collected from specimens in museum storage do not show a significant difference from those that are collected from live specimens. Depending on the type of processing a specimen undergoes, museum storage or processing may affect the scale patterns found on hairs of the pelage. If a significant amount of processing is involved, this is possible.

Lion guard hairs collected from the axillary region of a specimen in the Thomas M. Baker collection had no cuticle scale patterns, so only hairs collected from the fecal sample were imaged. When observing bristle and guard hairs collected from the taxidermic specimen, it was noted that bristle hairs are longer, thicker, and wavier in appearance than guard hairs. These differences allowed them to be distinguished from one another in the fecal samples. However, because guard hairs were collected from feces, it is uncertain from which part of the body these hairs originated.

As noted in similar studies, the most limiting factor of this study was the lack of hairs collected from different body regions of each species. Most guard hairs were collected from the dorsoscapular region of the pelage, and all of the bristle hairs were collected from the mane of the pelage. No hairs were collected from the posterior, ventral, or cranial regions of the animals. There are also no scale patterns representing hairs from juveniles; all hairs came from adults. Cuticular scales from different parts of the pelage, as well as hairs from juveniles, are thought to be different in appearance (Day 1966, Perrin and Campbell 1980, Keogh 1983, Seiler 2010). Another limiting factor is that only male nyalas were available for hair collection. Nyalas exhibit sexual dimorphism, so it is possible for genders to display differences in cuticular scale patterns.

We found two species that have unique scale patterns, making them easily identifiable under the use of a microscope. Impala have two types of scale patterns. The first scale pattern (Figure 1) appears streaked, with a raised surface running down the center of the hair shaft. The second (Figure 2) appears imbricate overall, with smooth, yet irregularly waved scales. Hairs containing both types of scale patterns were collected from the dorsoscapular area of the pelage, and there is no relationship between hair color and type of scale pattern. The same process was used to collect all hairs, so there is no correlation indicating why there are two distinct scale patterns. Steenbok hair contains scales that appear mosaic proximally and slowly transition into a smooth, coronal shape.

There are slight differences in appearance of the scale patterns between dark and light colored leopard guard hairs, indicating that different colored hairs could display differences in cuticular scale patterns. This was unexpected, as the hairs were collected from the same region of the pelage. This question was not addressed in this study, but could prove to be an important subject during similar future studies.

To produce a fully diagnostic key, the scale patterns found in this study should be studied along with medullary characteristics, color patterns, dimensions, and other diagnostic features of known reference hairs. We did also observe hairs from each species at 10 kV and 10,000× magnification to search for distinguishing characteristics at the extremely microscopic level. However, no additional distinctive features were found to discriminate among different species.

Acknowledgments

We thank all of the volunteers at Transfrontier Africa for their encouragement and support. We also thank Limpopo Taxidermy, the Louisville Zoo, and the Thomas M. Baker Collection for supplying hairs used for this project. Dr. John Andersland directs the electron microscopy facility and ensured best results. Funding for the project was provided by the Honors College and FUSE program at Western Kentucky University, Grant/Award Number: “15-FA218”.

References

  • Backwell, L., R. Pickering, D. Brothwell, L. Berger, M. Witcomb, D. Martill, K. Penkman and A. Wilson. 2009. Probable human hair found in a fossil hyaena coprolite from Gladysvale cave, South Africa. J. Archaeol. Sci. 36: 1269–1276. CrossrefWeb of ScienceGoogle Scholar

  • Braczkowski, A., L. Watson, D. Coulson and R. Randall. 2012. Diet of leopards in the southern Cape, South Africa. Afr. J. Ecol. 50: 377–380. Web of ScienceGoogle Scholar

  • Breuer, T. 2005. Diet choice of large carnivores in northern Cameroon. Afr. J. Ecol. 43: 181–190. CrossrefGoogle Scholar

  • Davidson, Z., M. Valeix, F.V. Kesteren, A.J. Loveridge, J.E. Hunt, F. Murindagomo and D.W. Macdonald. 2013. Seasonal Diet and Prey Preference of the African Lion in a Waterhole-Driven Semi-Arid Savanna. Plos One 8: e55182. Web of ScienceCrossrefGoogle Scholar

  • Day, N.G. 1966. Identification of hair and feather remains in the gut and faeces of stoats and weasels. J. Zool. Lond. 148: 201–217. Google Scholar

  • Deedrick, D.W. and S.L. Koch. 2004. Microscopy of Hair Part 1: A Practical Guide and Manual for Human Hairs. Forensic Science Communications [Online]. Available at: https://www2.fbi.gov/hq/lab/fsc/backissu/jan2004/research/2004_01_research01b.htm#refer. Accessed on October 16, 2015. 

  • Hess, W.M., J.T. Flinders, C.L. Pritchett and J.V. Allen. 1985. Characterization of Hair Morphology in Families Tayassuidae and Suidae with Scanning Electron Microscopy. J. Mammal. 66: 75–84. CrossrefGoogle Scholar

  • Homan, J.A. and H.H. Genoways. 1978. An analysis of hair structure and its phylogenetic implications among heteromyid rodents. J. Mammal. 59: 740–760. CrossrefGoogle Scholar

  • Johnson, M.K. and R.M. Hansen. 1979. Coyote Food Habits on the Idaho National Engineering Laboratory. J. Wildlife Manage 43: 951–956. CrossrefGoogle Scholar

  • Keogh, H.J. 1983. A photographic reference system of the micro-structure of the hair of southern African bovids. S. Afr. J. Wildl. Res. 13: 89–132. Google Scholar

  • Manfredi, C., M. Lucherini, A.D. Canepuccia and E.B. Casanave. 2004. Geographical Variation in the Diet of Geoffroy’s Cat (Oncifelis geoffroyi) in Pampas Grassland of Argentina. J. Mammal. 85: 1111–1115. CrossrefGoogle Scholar

  • Mansilla, J., P. Bosch, M.T. Menéndez, C. Pijoan, C. Flores, M.C. López, E. Lima and I. Leboreiro. 2011. Archaeological and contemporary human hair composition and morphology. Chungara: Revista de Antropología Chilena. 43: 293–302. Google Scholar

  • Mbizah, M.M., J. Marino and R.J. Groom. 2012. Diet of four sympatric carnivores in Savé Valley Conservancy, Zimbabwe: implication for conservation of the African wild dog (Lycaon pictus). S. Afr. J. Wildl. Res. 42: 94–103. CrossrefGoogle Scholar

  • Mizutani, F. 1999. Impact of leopards on a working ranch in Laikipia, Kenya. Afr. J. Ecol. 37: 211–225. CrossrefGoogle Scholar

  • Ott, T., G.I.H. Kerley and A.F. Boshoff. 2006. Preliminary observations on the diet of leopards (Panthera pardus) from a conservation area and adjacent rangelands in the Baviaanskloof region, South Africa. Afr. Zool. 42: 31–37. Web of ScienceGoogle Scholar

  • Perrin, M.R. and B.S. Campbell. 1980. Key to the mammals of the Andries Vosloo Kudu Reserve (Eastern Cape), based on their hair morphology, for use in predator scat analysis. S. Afr. J. Wildl. Res. 10: 3–14. Google Scholar

  • Rosas-Rosas, O.C., R. Valdez, L.C. Bender and D. Daniel. 2003. Food Habits of Pumas in Northwestern Sonora, Mexico. Wildlife Soc. B 31: 528–535. Google Scholar

  • Sahajpal V. and S.P. Goyal. 2009. Microscopic examiations in wildlife investigations. Microscopic examinations in wildlife investigations. Forensic science in wildlife investigations. CRC Press, Boca Raton, FL. pp. 19–59. Google Scholar

  • Seiler, N. 2010. SEM-Atlas of hair structures of South-African mammals. Mammalia 74: 281–290. Web of ScienceGoogle Scholar

  • Short, H.L. 1978. Analysis of cuticular scales on hairs using the scanning electron microscope. J. Mammal. 59: 261–268. CrossrefGoogle Scholar

  • Taru, P. and L. Backwell. 2013. Identification of fossil hairs in Parahyaena brunnea coprolites from Middle Pleistocene deposits at Gladysvale cave, South Africa. J. Archaeol. Sci. 40: 3674–3685. CrossrefWeb of ScienceGoogle Scholar

  • Taru, P. and L.R. Backwell. 2014. Hair morphology of some artiodactyls from southern Africa. Ann. Ditsong. Nat. Mus. Nat. Hist. 4: 26–32. Google Scholar

  • Verma, K. and B. Joshi. 2012. Different animal species hairs as biological tool for the forensic assessment of individual identification characteristics from animals of zoological park, Pragti Maidan, New Delhi, India. J. Forensic. Res. 3: 160. Google Scholar

  • Wentworth, J.C., C.J. Tambling and G.I.H. Kerley. 2011. Evidence for prey selection by spotted hyaena in the Eastern Cape, South Africa. Acta Theriol. 56: 389–392. CrossrefWeb of ScienceGoogle Scholar

  • Wilson, D.E. and D.M. Reeder (eds). 2005. Mammal species of the world. A taxonomic and geographic reference. Third edition. Johns Hopkins University Press, Baltimore. pp. 2142. Google Scholar

About the article

Received: 2016-04-26

Accepted: 2016-12-23

Published Online: 2017-02-21

Published in Print: 2017-12-20


Citation Information: Mammalia, Volume 82, Issue 1, Pages 12–22, ISSN (Online) 1864-1547, ISSN (Print) 0025-1461, DOI: https://doi.org/10.1515/mammalia-2016-0053.

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