Diversity in the Living World

Earth has numerous habitats with a wide range of living organisms inhabiting them. Plants and animals are present in almost all the places, from polar icecaps to volcanic hot springs, from shallow lagoons to the deepest oceans, from tropical rain forests to dry and parched deserts. There are a variety of species that have been adapted successfully tolive in diverse ­ecosystems. Ecosystem is a community of biotic and abiotic factors and their interrelationships (A.G. Tansley, 1935). The presence of a large number of species in a particular ecosystem is called ‘biological diversity’ or in short ‘­biodiversity’. The term biodiversity was first ­introduced by Walter Rosen (1985), and defined by E.D. Wilson.

Characterstic features of living organisms

Living organisms show a variety of unique characters different from non- living matter. The key characters of living organisms are, cellular organization, nutrition, respiration, metabolism, growth, response to stimuli, movement, reproduction, excretion, adaptation and homeostasis. Numerous scientists and taxonomists have made tremendous contribution and documentation in the observation and study of even minute characters in living organisms. Their keen observations have led to the classification of living organisms and the study of their interrelationships.