|Miocene (mī'ə-sēn') Pronunciation Key
The fourth epoch of the Tertiary Period, from about 24 to 5 million years ago. During this time the climate was warmer than it had been in the Oligocene, and kelp forests and grasslands first developed. With the isolation of Antarctica, a circumpolar ocean current was established in the southern Hemisphere, reducing the amount of mixing of cold polar water and warm equatorial water and causing a buildup of ice sheets in Antarctica. The African-Arabian plate became connected to Asia, closing the seaway which had previously separated Africa from Asia. Mammalian diversity was at its peak. See Chart at geologic time.
Dictionary.com presents 366 FAQs, incorporating some of the frequently asked questions from the past with newer queries.