Why are the small numbers of surviving tigers a cause of worry from the point of view of genetics?

Explanation

(i) If any natural calamity occurs and kills these small number of surviving tigers, they can become extinct resulting in the loss of genes forever.
(ii) Small number will lead to little recombination and lesser variations that are very important for giving better survival chances to the species.
(iii) Less number of species means lesser extent of diversity and lesser number of traits which reduce the chances of adaptability with respect to the change in the environment.