ALBERT

Description: The main purpose of this study is to search for an explanation of the curious differentiation within the genus Chamaeleo. Since the species of this genus are rather doubtful units, I have studied the geograpical distribution of characters, not of the species, a method first used in botany (BAUR, ROTHMALER a.o.). I found that the number of characters is largest in east Afrika, gradually decreasing from this area to the periphery of the total range of the genus. East Africa proved to be still more important, as practically all the characters occur in it. This means that the chameleons in the other areas practically never possess characters that are not found in east Africa.\nThis pattern of distribution fits in rather well with REINIG\xe2\x80\x99S elimination theory (1938): \xe2\x80\x9e.. bei Einzelwanderungen wird nur ein Teil des gesamten Allelbestandes einer Art mitgef\xc3\xbchrt... eine durch Einzelwanderung entstandene Population weist eine geringere Zahl von Allelen auf als die Ausgangspopulation.\xe2\x80\x9d The existence of many parallel series of variation (meaning that several characters originated several times independently in different groups) led me to the conclusion that the mechanism described in REINIG\xe2\x80\x99S theory as elimination, has consequences also for the genes predisposed to change into others.\nThis reasoning gave a key to the reconstruction of the ancestral chameleon. By two different ways I arrived at the same conclusion, viz. the ancestral chameleon was probably an animal resembling mostly Chamaeleo chamaeleon s.l. (\xc2\xa7 21).\nAs for this theoretical part of my study a survey of the species was needed, I first made an attempt at a natural system. I have divided the genus into groups of related species. For practical reasons the chameleons of Madagascar are treated separately. Their connections with the species of the African continent are examined in a special section (\xc2\xa7 11).\nAs a result of my investigations I had to propose the following taxonomic changes: Ch. rhinoceratus var. lineatus + Ch. labordi + Ch. voeltzkowi + Ch. barbouri = Ch. rhinoceratus (\xc2\xa7 3), Ch. lambertoni = Ch. lateralis (\xc2\xa7 4), Ch. semicristatus = \xe2\x99\x80 Ch. verrucosus (\xc2\xa7 5), Ch. guibei nov. spec. (\xc2\xa7 6), Ch. calcarifer = Ch. chamaeleon calcarifer, Ch. zeylanicus = Ch. chamaeleon zeylanicus, Ch. etiennei = Ch. gracilis etiennei (\xc2\xa7 12), Ch. anchietae vinkei + Ch. anchietae mertensi + Ch. marunguensis = Ch. anchietae (\xc2\xa7 13), Ch. unicornis = Ch. oweni unicornis (\xc2\xa7 14), Ch. pumilus = Ch. pumilus pumilus, Ch. melanocephalus = Ch. pumilus melanocephalus, Ch. gutturalis = Ch. pumilus gutturalis, Ch. ventralis = Ch. pumilus ventralis, Ch. ventralis occidentalis = Ch. pumilus occidentalis, Ch. ventralis karrooicus = Ch. pumilus karrooicus, Ch. damaranus = Ch. pumilus damaranus, Ch. caffer = Ch. pumilus caffer, Ch. taeniobronchus = Ch. pumilus taeniobronchus. (\xc2\xa7 16).