The Ordovician (/ ɔːrdəˈvɪʃi.ən, - doʊ -, - ˈvɪʃən / or-də-VISH-ee-ən, -⁠doh-, -⁠VISH-ən) [9] is a geologic period and system, the second of six periods of the Paleozoic Era, and the second of …

2024年12月24日 · Ordovician Period, in geologic time, the second period of the Paleozoic Era. It began 485.4 million years ago and ended 443.8 million years ago. The interval was a time of …

The Ordovician is best known for its diverse marine invertebrates, including graptolites, trilobites, brachiopods, and the conodonts (early vertebrates). A typical marine community consisted of …

2012年8月10日 · The Ordovician ended with the second greatest extinction event of the Phanerozoic Eon. Two massive reductions, a million years apart, created this event—resulting …

During the Ordovician period, part of the Paleozoic era, a rich variety of marine life flourished in the vast seas and the first primitive plants began to appear on land—before the second largest...

2023年4月28日 · Rocks from the Ordovician Period contain evidence that plants began colonizing dry land at this time. Most experts agree that the ancestors of land plants first evolved in a …

2023年1月23日 · The Ordovician Period is the second period of the Paleozoic Era (the first and longest era of the Phanerozoic eon). The era began about 541 million years ago with the …

The Ordovician, named after the Welsh tribe of the Ordovices, was defined by Charles Lapworth, in 1879, to resolve a dispute between followers of Adam Sedgwick and Roderick Murchison, …

2024年10月12日 · The Ordovician Period is the second period of the Paleozoic Era, following the Cambrian Period and preceding the Silurian Period. It lasted from approximately 485 million …

Ordovician Period, Interval of geologic time, 485.4–443.4 million years ago, the second oldest period of the Paleozoic Era. It follows the Cambrian and precedes the Silurian Period. During …