THE FUTURE FOSSIL RECORD OF THE ANTHROPOCENE

Human activities have produced unprecedented changes in the ecology of terrestrial vertebrate species, including dramatic shifts in population size and demographics, major modifications in ranges, and alterations in body size distributions. These are associated with defaunation, local extirpations, invasions and introductions, and global extinctions. There have been contemporaneous unparalleled changes in surface environments, including those associated with preservation potential. A consideration of the current and near future input of mammalian remains to the terrestrial record indicates a marked shift from the Pleistocene and Holocene. Humans have had a major impact on the “supply side” of the fossil record for millennia, going back to the extinction at the end of the Pleistocene. The potential fossil record will be dominated by a cosmopolitan fauna of humans and their domestic animals. Wild animals will be rare and tend to be smaller, again with a cosmopolitan distribution due to human introductions. The chance of a wild animal becoming part of the fossil record has become very small; instead, the future record will be mostly cows, chickens, pigs, sheep, goats, dogs, cats, etc., and people themselves. If preserved, this will produce an unmistakable biostratigraphic unit. In addition to changes in the input of mammal remains, there are and continuing to be major anthropogenic impacts on the preservation potential of fossil vertebrates, which will produce a new and unique taphonomic signature. These impacts include changes in the distribution and properties of natural sites of preservation and the production of novel sites for preservation. Most of these are associated with long-term changes in land use and climate change. These include draining of wetlands, modifications of rivers by straightening and damming, and major increases in rates of erosion. There are key changes in the distribution in the distribution and chemistry of soils and sediments by the advent of large scale agriculture. The use of large agricultural equipment and increased domestic animal density due to intensive animal farming in limited areas likely increases the rate and changes the kind of damage to bones. In sum, the modern era, informally dubbed the Anthropocene, should produce a fossil record that is unique in Earth history.