Question

Explain the importance of fossils in deciding evolutionary relationships.

Answer 1

Hint: It tells about the relationship between an individual and its ancestor.

Complete answer:
An evolutionary tree also called a phylogenetic tree is the study of determining phylogenetic relationships or patterns of the descent of organisms.
Evolutionary relationships indicate which ancestors give rise to which descendants.
Fossils are the preserved remains or traces of ancient organisms. They are in the form of rock.
Fossils provide the knowledge of animals and plants that lived hundreds of years ago which are now extinct. It helps us to compare the organisms that lived in earlier times and their present descendants.
They are the connecting link between two groups and help in the study of evolution.

Importance of fossil
- Fossils present at the bottom of the rock are simple while the ones which are present at the top are the most recent fossils. This succession revolves around evolution.
- They sometimes provide a direct link between two groups, for example, Archaeopteryx which is the connecting link between birds and reptile-like ancestors.
- Fossils of the dinosaur bodies have been found in the rocks which were meant to give them warmth. This indicates that the dinosaur later evolved into flying ones by developing wings like birds. This shows an evolutionary relationship between birds and reptiles.
- The fossil record of certain mammals can be studied in a series of evolution by looking into their geological time scale.

Note: The geological time scale is the “calendar “ for the events in Earth history. It is a system of chronological dating that relates geological strata with time. It subdivides time into certain units in descending order of duration, and are named as – eons, eras, periods, epochs, and ages.