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[18] [19] The Pleistocene covers the recent period of repeated glaciations. The name Plio-Pleistocene has, in the past, been used to mean the last ice age. Formerly, the boundary between the two epochs was drawn at the time when the foraminiferal species Hyalinea baltica first appeared in the marine section at La Castella, Calabria, Italy. [20]
The Holocene (/ ˈ h ɒ l. ə s iː n,-oʊ-, ˈ h oʊ. l ə-,-l oʊ-/) [2] [3] is the current geological epoch, beginning approximately 11,700 years ago. [4] It follows the Last Glacial Period, which concluded with the Holocene glacial retreat. [4] The Holocene and the preceding Pleistocene [5] together form the Quaternary period.
During the Pliocene epoch (5.3 to 2.6 million years ago (Ma)), the Earth's climate became cooler and drier, as well as more seasonal, marking a transition between the relatively warm Miocene to the cooler Pleistocene. [19] However, the beginning of the Pliocene was marked by an increase in global temperatures relative to the cooler Messinian.
It features modern animals, and dramatic changes in the climate. It is divided into two epochs: the Pleistocene and the Holocene. The Pleistocene lasted from 2.58 million to 11,700 years ago. This epoch was marked by a series of glacial periods as a result of the cooling trend that started in the mid-Eocene. There were numerous separate ...
During the present interglacial, the Holocene, the climatic optimum occurred during the Subboreal (5 to 2.5 ka BP, which corresponds to 3000 BC–500 BC) and Atlanticum (9 to 5 ka, which corresponds to roughly 7000 BC–3000 BC). The current climatic phase following this climatic optimum is still within the same interglacial (the Holocene).
Oak and hemlock species were also found in Pliocene-era pollen records, and their absence in Pleistocene records has led climatologists to hypothesize that their absence is indicative of a moisture decrease from the Pliocene to the Pleistocene. [3] A cooling, drying trend has been interpreted from the Bruneau, Idaho sediment core.
The Quaternary (/ k w ə ˈ t ɜːr n ə r i, ˈ k w ɒ t ər n ɛr i / kwə-TUR-nə-ree, KWOT-ər-nerr-ee) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS), as well as the current and most recent of the twelve periods of the Phanerozoic eon. [3]
The Holocene extinction, also referred to as the Anthropocene extinction, [3] [4] is an ongoing extinction event caused by human activities during the Holocene epoch. This extinction event spans numerous families of plants [ 5 ] [ 6 ] [ 7 ] and animals, including mammals , birds, reptiles, amphibians , fish, and invertebrates , impacting both ...