New Zealand's biota is interesting on an international scale for many reasons. For example, though one usually thinks of New Zealand as an island or archipelago, it is also one of the world's smallest continents, defined biogeographically as a land mass within which birds and mammals can achieve completed speciation not dependent on water gaps. Its biota arrived both over water during a long time and over land in the far-distant past, and then redistributed itself within the modern New Zealand archipelago both over land (at Pleistocene times of low sea level) and over water. The biotas of New Zealand and Madagascar are the closest we shall ever come to observing the products of continental evolution in island-like isolation, unless we discover higher life on another planet. Finally, New Zealand is distinctive in the two-stage destructive impacts it received from human colonists, and in the innovativeness with which its biologists are now seeking to mitigate those impacts. All these features make New Zealand one of the world's biological prizes