Malays. Appl. Biol. 41(1): 1–10
MORPHOLOGICAL VARIATION OF MOUNTAIN BLACKEYE (Chlorocharis emiliae) POPULATIONS IN MALAYSIAN BORNEO
RAMJI, M.F.S.1*, RAHMAN, M.A.1 and TUEN, A.A.2
1Department of Zoology, Faculty of Resource Science and Technology
2Institute of Biodiversity and Environmental Conservation Universiti Malaysia Sarawak, 94300 Kota Samarahan, Sarawak, Malaysia.
*Email:
This e-mail address is being protected from spambots. You need JavaScript enabled to view it
ABSTRACT
The mountain blackeye (Chlorocharis emiliae) is one of the few Bornean endemic birds which presents an excellent model species to illustrate evolution and speciation. Here, we use discriminant function analysis to elucidate the morphological variation on 40 specimens of mountain blackeye from four populations namely Mount Kinabalu, Mount Trus Madi, Mount Murud and Mount Mulu. The test successfully distinguished all four populations accordingly by respective nominated subspecies. Tarsus length and bill length were identified as the best predictors from nine character loadings observed which also included bill depth, bill width, head bill, wing length, wing span, tail length and total length. Along with this, the morphological patterns also revealed that solid skeletal characters such as bill length, bill depth, bill width and tarsus are genuine predictors of morphological variation and body size within species as compared to feather-based characters. The evolution of such morphological traits is more pronounced due to different ecological adaptation of the mountain blackeye populations. Several factors such as phenotypic plasticity, foraging behaviours and food availability may have influenced the morphological variation between the subspecies.
Key words: character loading, evolution, foraging behaviours, morphological variation, phenotypic plasticity, subspecies
REFERRENCES
Argent, G., Lamb, A., Phillipps, A. and Collenette, S. 1988. Rhododendrons of Sabah. Sabah Parks Trustees.
Badyaev, A.V. and Martin, T.E. 2000. Individual variation in growth trajectories: phenotypic and genetic correlations in ontogeny of the house finch (Carpodacus mexicanus). Journal of Evolutionary Biology. 13: 290-301.
Banks, E. 1952. Mammals and Birds from the Maga Mountains in Borneo. Bulletin Rafflesia Museum 24: 160-163.
Bokma, F. 2004. Why most birds are small: A macro-ecological approach to the evolution of avian body size. Department of Biology, University of Oulu, Oulu University Press, Finland.
Bland, J.M. and Altman, D.G. 1996a. Statistics Notes: Logarithms. British Medical Journal. 312: 700.
Bland, J.M. and Altman, D.G. 1996b. Statistics Notes: Transforming data. British Medical Journal. 312: 770.
Carrascal, T.M., Moreno, L. and Telleria, J.L. 1990. Ecomorphological relationships in a group of insectivorous birds of temperate forests in winter. Holarctic Ecology. 13: 105-111.
Chaves, J.A., Pollinger, J.P., Smith, T.B. and Lebuhn, G. 2007. The role of geography and ecology in shaping the phylogeography of the speckled hummingbird (Adelomyia melanogenys) in Ecuador. Molecular Phylogenetics and Evolution. 43: 795-807.
Corbin, C.E. 2002. Morphological and ecological evolution in old and new world flycatchers. PhD thesis. The faculty of the College of Arts and Sciences of Ohio University, Ohio.
Dalet, D. 2011. Map of Malaysia. http://dmaps.com/ m/malaisie/malaisie08.gif. Downloaded 25 November 2011.
Davison, G.W.H. 1992. Birds of Mount Kinabalu- Borneo. Natural History Publications (Borneo) Sdn. Bhd. and Koktas Sabah Berhad, Sabah.
Förschler, M.I. and Siebenrock, K.H. 2007. Morphological differentiation of mainland Citril Finches, Carduelis [citrinella] citrinella and insular Corsican (Citril) Finches, Carduelis [citrinella] corsicanus. Bonner Zoologische Beiträge. 55: 159-162.
Gawin, D.F.A. 2006. Patterns of variation in the mountain blackeye (Chlorocharis emiliae) in selected mountaintops in Sabah and Sarawak, Malaysia. MSc Thesis. Faculty of Resource Science and Technology, Universiti Malaysia Sarawak.
Gill, F.B. 1990. Ornithology. W H. Freeman and Company, New York.
Grieco, F. 2003. Greater food availability reduces tarsus asymmetry in nestling blue tits. The Condor. 105: 599-603.
Harrison, T. 1955. The mountain black-eye (Chlorocharis): Ecology and Natural History. The Sarawak Museum Journal. 6: 663-687.
Harrison, T. 1956. A new mountain black-eye (Chlorocharis) from North Borneo. The Sarawak Museum Journal. 8: 516-521.
Jensen, H., Saether, B.E., Ringsby, T.H., Tufto, J.H., Griffith, S.C. and Ellegren, H. 2003. Sexual variation in heritability and genetic correlations of morphological traits in house sparrow (Passer domesticus). Journal of Evolutionary Biology. 16: 1296-1307.
Johnston, F.G. 1992. Geographic size variation in rock pigeons, Columba livia. Bollettino di Zoologia. 59: 111-116.
Larson, A. 1989. The relationship between speciation and morphological evolution. Speciation and Its Consequences. Sinauer Associates, Inc. Publishers, Sunderland, Massachusetts.
Lougheed, S.C. and Handford, P. 1993. Covariation of morphological and allozyme frequency characters in populations of the rufous-collared sparrow (Zonotrichia capensis). The Auk. 110(2): 179-188.
Manly, B.F.J. 1994. Multivariate statistics: a primer, second edition. Chapman and Hall, London.
Mees, G.F. 1955. The mountain black-eye (Chlorocharis): Ecology and Natural History. The Sarawak Museum Journal. 6: 663-687.
Myers, S. 2009. A field guide to the birds of Borneo. New Holland Publication, UK.
Keller, L.F., Grant, P.R., Grant, B.R. and Petren, K. 2001. Heritability of morphological traits in Darwin’s Finches: misidentified paternity and maternal effects. Heredity. 87: 325-336.
Kershaw, F.L.A. 2006. The co-evolution of hummingbird bill morphology and floral structures with regard to both native and non- native flower species. Department of Biology, School of Biological Sciences, Leeds University, Leeds, LS2 9JT.
Kleindorfer, S., Chapman, T.W., Winkler, H. and Sulloway, J. 2006. Adaptive divergence in contiguous populations of Darwin’s Small Ground Finch (Geospiza fuliginosa). Evolutionary Ecology Research. 8: 357-372.
Rahman, M.A. 2000. Biogeography of Avifauna and Patterns of Variation in the Little Spiderhunter (Arachnothera longirostra) in Southeast Asia. PhD thesis. - Department of Zoology, University of Queensland, St. Lucia.
Ramji, M.F.S. 2010. Patterns of plumage colouration, genetic and morphological variation in mountain blackeye (Chlorocharis emiliae) from Malaysian Borneo. MSc Thesis. Faculty of Resource Science and Technology, Universiti Malaysia Sarawak.
