Miocene

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The Miocene

The Miocene is the first epoch of the Neogene period of the Cainozoic. It started about 23 million years ago and ended about 5.33 million years ago. The rock beds that mark the start and end are well known, but the exact dates of the start and end of the period are uncertain. The biota becomes 'modern'.

The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words μείων (meiōn, “less”) and καινός (kainos, “new”) and means "less recent", because it has 18% fewer modern sea invertebrates than the Pliocene.

As the earth cooled, it went from the Oligocene epoch, through the Miocene, and into the Pliocene. The Miocene boundaries are not set at any particular world wide event. They are set at regional boundaries between the warmer Oligocene and the cooler Pliocene epochs.

The plants and animals of the Miocene were fairly modern. Modern families of mammals and birds existed. Whales, seals, and kelp spread. Modern sharks appeared, including the huge Megalodon. Grasslands became more common. Mammalian browsers became less common, and grazer species became more common. About 100 species of ape lived at that time, and cetaceans were very common in the seas.[1] The giganic shark Carcharodon megalodon may have preyed on them.

References[change | change source]

  1. Alton C. Dooley Jr., Nicholas C. Fraser & Zhe-Xi Luo (2004). "The earliest known member of the rorqual–gray whale clade (Mammalia, Cetacea)" (PDF). Journal of Vertebrate Paleontology 24 (2): 453–463. doi:10.1671/2401 . http://www.seaturtle.org/PDF/Dooley_2004_JVertPaleo.pdf.