Question

why are fossil considered important in the study of evolution explain two way by which age of fossil can be astimite

Answer 1

Fossils are used importantly in the study of the Laws of Fossil Succession, according to which - 

1. Fossils represent the remains of once-living organisms.

2. Most fossils are the remains of extinct organisms; that is, they belong to species that are no longer living anywhere on Earth.

3. The kinds of fossils found in rocks of different ages differ because life on Earth has changed through time.

Darwin's theory of evolution accounts for all of the diversity of life, both living and fossils. According to Darwin, the evolution of life is caused by four processes: variation, over-reproduction, competition, and survival of those best adapted to the environment in which they live.

Scientific theories are continually being corrected and improved based on the known facts, observations and as new knowledge is gained, a theory may change. Application of these theories allows us to develop new plants that resist disease, to transplant kidneys, to find oil, and to establish the age of our Earth.

Scientists look for ancestors and descendants through geologic time. Scientists combine several well-tested techniques to find out the ages of fossils. The most important are Relative Dating, in which fossils and layers of rock are placed in order from older to younger, and Absolute dating or Radiometric Dating, which allows the actual ages of certain types of rock to be calculated. Relative and Radiometric Dating Together can be used together to find the ages of volcanic layers in a stack of sedimentary rock. Index fossil indicates a particular time period and the similarities can be drawn to identify new species.