Question

Give an example of characteristics being used to determine how close two species are in evolutionary terms.

Answer 1

Different organisms with
common ancestry in the past, are
more likely to have similar
characteristics due to
inheritance. These similar
characteristics are used to
determine evolutionary
relationships. Basic structure of
Forelimbs in human and birds is
one such example of a
characteristic which shows
closeness of two species in
evolutionary terms. The forelimbs
in both the species, have similar
bones structure and similar
origin, but, over period of time,
spanning generations, they have
been developed to perform
different suitable functions as
per the need. Such organs that
have similar basic structure but
perform different functions are
called homologous organs. These
are used to find out evolutionary
relationships.

Answer 2

Organisms who have the same ancestors will have same characteristics.

For example take the case of the fore limbs  frog and the hands of humans.

they  have same structure but different function this shows that they were linked to each other  but due to evolution they have been changed