Late Cenozoic Fossil Coleoptera: Evolution, Biogeography, and Ecology

Abstract

The recent revival of interest in the fossil insects of the Quaternary Period [the last 1 .6 million years (68, 69)] has been summarized in the Annual Review of Entomology (21). The present essay was originally intended as a second installment to that earlier review, drawing attention to significant developments since that time. However, the important discoveries of late . Miocene fossil insects in Alaska and the Canadian Arctic Archipelago (52) have such a direct bearing on the evolution of the Quaternary and hence the present day fauna that I widened my scope to include these faunas. Studies of the Late Cenozoic biota straddle the boundary between classical palaeontology and neontology, providing vital evidence on the course and rates of evolution, changes in biogeography, and the ecological history of the present biota. While it may be that fossils from the remote past have only marginal relevance to the understanding of the present day biota and its environment, the fossil record from the Late Cenozoic cannot be brushed aside so easily. In many cases these fossils represent the immediate ancestors of our living species, and the ecosystems in which they lived were the precursors of those of the present day. The relatively recent fossil history of insects, long a no-man's-land between biology and classical palaeontology, has been badly neglected. Only in the past two decades has a systematic attempt been made to unravel the Late Cenozoic fossil record of the insects, the most abundant, taxonomically diverse, and ecologically varied component of terrestrial fossil assemblages.