Abstract
A consensus on the subspecific classification of Red Junglefowl (Gallus gallus) is not to be reached yet. The subspecies of Red Junglefowl have generally been classified according to their range, plumage and earlobe color. However these characters are all somewhat problematic. Red Junglefowl is usually found lurking in bushes. But this vegetation varies widely among the various climates that make up their extensive habitat, and it is possible that variations in Junglefowl plumage are caused by such differences in environment. Plumage color is also affected by breeding season. Furthermore the assessment of the plumage color is influenced by observation conditions and open to observer subjectivity. Red or white earlobe color has been used as an important index for subspecific classification. However, it has been reported that white earlobes are not a character expressed by a single gene. Moreover, white earlobe coloration varies considerably among white lobed individuals. Therefore, using earlobe color alone as the standard for subspecific classification is unsuitable. Of the five subspecies of G. gallus, G. g. murghi, G. g. jabouillei, and G. g. bankiva are unambiguously classified by size and plumage. Likewise the white earlobe of G. g. gallus distinguishes it from the red lobed G. g. spadiceus. Within G. g. gallus, however, two types of white earlobe coloration are found. G. g. gallus in Thailand has a complete white earlobe and G. g. gallus in Malaysia has an incomplete white earlobe. In both Malaysia and Thailand, populations of G. g. gallus are divided by the habitat of G. g. spadiceus. Yet despite geographical separation and different earlobe coloration, both types of G. g. gallus have until now been classified together. It is possible to divide G. g, gallus into two types using the character white earlobe 'complete' or 'incomplete'. Studies using mtDNA have similarly divided G. g. gallus into two types. Therefore, subspecific classification of Red Junglefowl should take into account new morphological information, geographical information, and results of molecular studies.
