Which of the following organs,when found to be present in two animals,indicate that these two animals have been evolved from a common ancestor?

There is a sub-population $A$ and another sub-population $B$. Both are separated by a natural barrier. What will happen in such a case?

Natural selection directs evolution as it results in adaptations in a given population.

Explain the following scenarios in a group of organisms,providing reasons for each:
$(a)$ Predators are more in the group.
$(b)$ Organisms survive accidentally.
$(c)$ Organisms are not able to survive in changing environmental conditions.

Select the incorrect statement.

Select the incorrect statement.