Zoology - Organisms and Populations Question with Solution | TestHub

Population evolve to maximize their reproductive fitness in the habitat in which they live. This fitness towards maximizing reproductive is called as Darwinian fitness (high r-value). According to this, under a particular set of selection pressures, organism evolves towards the most efficient reproductive strategy. Some of these are as follows:

(i) BREEDING HABIT: Some organisms breed only once in their lifetime (pacific salmon fish) while others breed many times during their lifetime (most bird and mammals)

(ii) NUMBER AND SIZE OF OFFSPRING: Some produce a large number of small-sized offspring (oysters, pelagic fishes) while others produce a small number of large-sized offspring (birds and animals).