As currently defined, the Holocene is by far the shortest geological epoch within the established geological time scale, limited to roughly the last 11,500 calendar years (10,000 14C years). As Zalasiewicz et al. (2011b) noted, the “Holocene
is really just the last of a series of interglacial climate phases that have punctuated the severe icehouse climate of the past 2 Myr. We distinguish it as an epoch for practical purposes, in that many of the surface bodies of sediment selleck chemical on which we live—the soils, river deposits, deltas, coastal plains and so on—were formed during this time.” As such, the Holocene is a relatively arbitrary construct that would not have appeared Raf inhibitor particularly dramatic or lasted long if humans had not contributed
to biological and ecological changes around the world. Defining an Anthropocene epoch that begins in AD 1850, AD 2000, or another very recent date would ignore a host of archeological and paleoecological data sets. It will also exacerbate the arbitrary and short-lived nature of the Holocene. In examining the evidence for human transformation of the global biosphere during three phases of human history—the Paleolithic, Neolithic, and Industrial ages—Ellis (2011:1012–1013) had this to say of the Neolithic: Agricultural human systems set the stage for sustained human population growth for millennia, from a few million in 10,000 BCE to billions today. More importantly, these systems are sustained by an entirely novel biological process—the Pyruvate dehydrogenase lipoamide kinase isozyme 1 clearing of native vegetation and herbivores
and their replacement by engineered ecosystems populated with domesticated plant and/or animal species whose evolution is controlled by human systems. Were these agroecosystems to attain sufficient global extent, endure long enough and alter ecosystem structure and biogeochemical processes intensively enough, these alone may represent a novel transformation of the biosphere justifying a new geological epoch (references omitted from original). In this paper, I have added to the widespread changes caused by early agricultural and pastoral peoples to Earth’s terrestrial ecosystems, documenting a post-Pleistocene proliferation of anthropogenic shell midden soils in coastal and other aquatic settings worldwide. The global intensification of fishing and maritime economies near the end of the Pleistocene adds nearshore marine habitats to the list of ecosystems Homo sapiens has altered for millennia. By the Terminal Pleistocene or Early Holocene, agricultural and maritime peoples together had widespread and transformative effects on the terrestrial and nearshore ecosystems they lived in.