251 million years ago
The five mass extinctions that occurred in Earth's history took place during the Ordovician period (about 445 million years ago), the Devonian period (about 375 million years ago), the Permian period (about 251 million years ago), the Triassic period (about 200 million years ago), and the Cretaceous period (about 66 million years ago).
The Paleozoic era is the longest out of the options given, lasting from about 541 million years ago to 252 million years ago. The Jurassic period is part of the Mesozoic era, which followed the Paleozoic era. The Carboniferous period occurred within the Paleozoic era.
The Triassic Period occurred before the Jurassic Period. The Triassic Period lasted from about 251 million to 201 million years ago, while the Jurassic Period followed, lasting from about 201 million to 145 million years ago.
No the Cambrian Period came before the Jurassic Period.Periods in the Paleozoic Era (542 - 251 Ma) and the Mesozoic Era (251 - 65.5 Ma)Cambrian (542 - 488.3 Ma)Ordivician (488.3 - 443.7 Ma)Silurian (443.7 - 416 Ma)Devonian (416 - 359.2 Ma)Carboniferous (359.2 - 299 Ma)Permian (299 - 251 Ma)Triassic (251 - 199.6 Ma)Jurrasic (199.6 - 145.5 Ma)Cretaceous (145.5 - 65.5 Ma)
They dominated the Earth for over 160 million years, from the late Triassic period (about 230 million years ago) until the end of the Cretaceous period (65 million years ago).
Pliosaurs lived from 251 to 65 million years ago
It is about 251 million years ago
251 million years ago
The five mass extinctions that occurred in Earth's history took place during the Ordovician period (about 445 million years ago), the Devonian period (about 375 million years ago), the Permian period (about 251 million years ago), the Triassic period (about 200 million years ago), and the Cretaceous period (about 66 million years ago).
The Mesozoic Period (251 - 65 million years ago) lasted approximately 216 million years. It consisted of the Triassic Period (251 - 200 million years ago), the Jurassic Period (199-146 million years ago) and the Cretaceous Period (145 - 65 million years ago).
The Paleozoic Era began about 540 million years ago and ended about 245 million years ago. Therefore, it lasted about 290 million years. Sources: My Earth Science book and my great brain.
These terms refer to the three major divisions of the geologic time scale. The Paleozoic era represents the earliest era, from about 541 to 251 million years ago. The Mesozoic era follows, spanning from about 251 to 66 million years ago, and is known for the age of dinosaurs. The Cenozoic era is the most recent era, starting about 66 million years ago and continuing to the present day.
Paleozoic, Mesozoic, and Cenozoic refer to periods in Earth's history. The Paleozoic era began 542 million years ago and ended 251 million years ago. The Mesozoic era is the age of dinosaurs and was from 245 to 66 million years ago. The Cenozoic period began 65 million years ago and continues today.
251 million in Scientific Notation = 2.51 x 108
At the end of the Permian Period which was about 251 million years ago
2.51 million written in number form is 2,510,000