This work explores the nature and extent of the use of clothing in the pre-colonial Australian Aboriginal population. Anthropological reviews have indicated that while a total absence of clothing was the usually the case, garments were sometimes worn. Clothing appears to have been used almost exclusively for reasons of warmth, and the geographical distribution seems to be consistent with an essentially thermal pattern. Clothes are documented in the cooler southern and southeastern areas of the continent, and more frequently in the cooler seasons. The garments were of a single-layer, draped variety, hung loosely from the shoulders. They generally took the form of capes or cloaks, and were manufactured from marsupial skins, mainly kangaroo or wallaby hides, or a number of opossum furs sewn together. These items served additionally, and sometimes primarily, as mats or rugs, and as bags or containers, the latter especially among women, who also used them to carry their infants. However, one problem with this ethnographic picture is that the Aborigines of Tasmania apparently made less use of clothing than did their counterparts across the Bass Strait. This "Tasmanian clothing paradox", referring to the fact that the Tasmanians would be expected to use at least as much clothing as Aborigines on the southern mainland, forms the focus of this study. A systematic analysis of the ethnographic record forms the main study. It comprises first-hand observations of the use of clothing by Aborigines prior to, and in the decades following, the beginning of the colonial era, in relation to latitude and various meteorological indices. A separate study indicates not only that morphological variation within the mainland Aboriginal population manifests strong thermal trends, but also that the Tasmanian Aborigines may have developed greater morphological cold adaptations. A third study is included, in which thermal factors are explored in relation to one of the archaeological challenges posed by the Tasmanian Aborigines, namely their utilization of cave sites in the remote southwest region of the island during the latter part of the last ice age.