Question

Which is the correct order of increasing geological time scale for a hypothetical vertebrate evolution?
(a)Cenozoic, Mesozoic, Palaeozoic, Precambrian
(b) Cenozoic, Palaeozoic, Mesozoic, Precambrian
(c) Precambrian, Cenozoic, Palaeozoic, Mesozoic
(d) Precambrian, Palaeozoic, Mesozoic, Cenozoic

Answer 1

Hint: The system of chronological dating that tells the geologic history of Earth in time is known as a geologic time scale. Geologists, paleontologists, and other scientists use this for knowing the relationship of different events occurring in geologic history.

Complete answer:
The geological time starts with Eons that have a subclass of Eras that are again divided into Periods and this may be subdivided into Epochs. The time of origin and the dominance of a certain group of animals can be determined by these Eras, Periods, and Epochs which also provide the most pieces of evidence for the concept of evolution. It begins with Archean Eon which is 4.0 billion to 2.5 billion years ago and contains the oldest rocks on earth. Next is the Proterozoic Eon which is 2.5 billion to 542 million years ago and life started here with the basic forms of organisms. Lastly, the Phanerozoic Eon which is 542 million years ago to the present day and this has a bit more advanced life forms. The Phanerozoic Eon can further be classified as Eras. This has four eras starting from the Precambrian Era which is the earliest part of earth's history and origin of the first animal, second Paleozoic Era has the ancient life like trilobites that is the age of fishes and amphibians, third Mesozoic Era is the middle life with the age of reptiles like dinosaurs, and lastly, Cenozoic Era is the recent life with mammals and flowering plants.
So, the correct option is 'Precambrian, Palaeozoic, Mesozoic, Cenozoic'.

Note: The geological time scale started with a time scale being prepared with the age of rocks. Earth has different layers of sediments with the bottom layer being the oldest layer and the upper layer being the most recent layer formed by different rocks crushed down due to environmental factors. It also indicates the organisms of the past millions of years back and different stages of the evolution of life.