The Holocene Epoch is a geologic period that extends from the present back about 10,000 radiocarbon years. The beginning of the period is often converted to approximately 11,000 calendar years using an approximate radiocarbon calibration. 11,000 years before 1950 is -9050 (9051 BC). The Holocene starts late in the retreat of the Pleistocene glaciers. The Holocene follows the Pleistocene Epoch and is the second and last epoch of the Quaternary period. The name is derived from the Greek holos (entire(ly)) and ceno (new). It has also been called the "Alluvium Epoch".
Continental motions are negligible over a span of only 10,000 years -- less than a kilometer. However, world sea levels rose about 35 meters (110 feet) in the early part of the Holocene due to ice melt. In addition, many areas above about 40 degrees latitude had been depressed by the weight of the Pleistocene glaciers and rose as much as 180 meters over the late Pleistocene and Holocene. The sea level rise and temporary land depression allowed temporary marine incursions into areas that are now far from the sea. Holocene marine fossils are known from Vermont, Quebec, Ontario and Michigan. Other than higher latitude temporary marine incursions associated with glacial depression, Holocene fossils are found primarily in lakebed, floodplain, and cave deposits. Holocene marine deposits along coastlines are rare because the rise in sea levels during the period exceeds any likely upthrusting of non-glacial origin.
Although geographic shifts in the Holocene were minor, climatic shifts were very large. Habitable zones expanded Northwards. Large mid-latitude areas that were previously productive became deserts. The epoch started with large lakes in many areas that are now quite arid. It is possible that the Holocene warming is merely another interglacial period and does not represent a permanent end to the Pleistocene glaciations. Animal and plant life did not evolve much during the Holocene, but there were major shifts in the distributions of plants and animals. A number of large animals including mammoths and mastodons, saber tooth cats, and giant sloth disappeared in the late Pleistocene and early Holocene -- especially in North America. Throughout the world, cooler climate ecosystems that were previously regional have been isolated in higher altitude ecological "islands".