Question

Jurassic period belongs to the era
(a) Palaeozoic
(b) Mesozoic
(c) Cenozoic
(d) Proterozoic

Answer 1

The Jurassic period was a geologic period in the Phanerozoic eon that started from the end of the Triassic Period 201.3 million years ago and lasted for 56 million years until the beginning of the Cretaceous Period 145 million years ago. It belongs to the era also known as the ‘Age of reptiles.’

Complete Step by Step Answer:
- The Jurassic period constituted the middle period of the Mesozoic Era that was also known as the 'age of reptiles'.
- The Jurassic period is named after the Jura Mountains in European Alps. It is because the limestone strata from the period were first identified there.
- The start of this period was supposedly marked by a major Triassic- Jurassic extinction event.
- The Jurassic period consists of three different epochs namely early, middle, and late.
- By the start of the Jurassic period, the supercontinent Pangaea had started rifting into two huge landmasses that came to be known as Laurasia to the north, and the Gondwana to the south.
- In the Jurassic period, the land fauna was dominated by dinosaurs alone.
- This period is also characterized by the appearance of the first birds, that had evolved from a branch of theropod dinosaurs.
- Other major events also included the appearance of the lizards, and the evolution of prototherian mammals and primitive placentals.

So, the correct answer is, '(b) Mesozoic'

Note:
The phanerozoic eon of the timescale is divided into three major eras: The Palaeozoic era, the Mesozoic era, and the Cenozoic era.
- The Paleozoic Era is the earliest and the longest of the Phanerozoic eras, lasting from 541 to 251.902 million years ago and it was also known as the “Cradle of ancient life.”
- The Mesozoic Era came next and lasted from 251.902 to 66 million years ago which includes the Triassic, Jurassic, and Cretaceous periods.
- The Cenozoic Era is the most recent and extends from 66 million years ago to the present day.
- Proterozoic era was characterized by the deposition of large amounts of sediment.