Why bats? Well, most folks in one of the many branches of the biological sciences have a special interest in certain organisms - that one group that you find intriguing, fascinating, amazing, and for which you have an endless curiosity. For me, it is bats (Class Mammalia, Order Chiroptera).
Microchiropteran bats of the Australian and Papua New Guinea region represent an interesting vehicle to study how faunas change over evolutionary (long) and ecological (short) timespans. The fossil evidence suggests that some groups of microbats have had a considerable evolutionary history in the region. Other evidence, though weaker, indicates that some groups may have had a more recent arrival and radiation within Australia and PNG. This might be good point to stress some important aspects of the zoogeography and macroecology of the region. First, Australia, Tasmania, and PNG form a single tectonic unit. PNG is very complex geologically becasue is being formed by the collision of the Pacific and Indo-Australian tectonic plates and, instead of disappearing into a subduction zone, is being buckled upwards. Second, the fracturing and contortions of the Asia region into which Australia and PNG are ploughing suggests that there may well have been many islands or continental fragments stretching away from Australia's northern margin for a considerable period of time. This could have permitted the exchange of flora and fauna over millions of years. For example, the importance of such dispersal pathways has been suggested for palms and passerine birds where two-way traffic has seen the development of a mixed pool of taxa in Australia and PNG - some so-called "old endemics" with clear links to Gondwana, and more recent arrivals.
Extreme climate change has accompanied Australia's move northwards, but the rate of change is slow compared to the likely impacts of human-induced climate change. Mammals generally, but bats in particular, have not received as much attention with respect to climate change as other groups such as butterflies and plants. And, in the Australian setting, this neglect continues - an important recent publication (Law et al. 2011) which provides an overview of the current state of knowldege of the Australasian bat fuana and its conservation issues, does not mention climate change more than briefly...which brings us to the topic of the species distribution models presented here.