Assertion: Ecological equivalents possess similar types of adaptations. Reason : Ecological niche is the total interaction of species with the environment. A. If both assertion and reason are true and the reason is the correct explanation of the assertion. B. If both assertion and reason are true and the reason is not the correct explanation of the assertion. C. If the assertion is true but reason is false. D. If both assertion and reason are false.
Hint: Grinnell first emphasised the concept of 'ecological equivalents' in 1924.
Complete Answer: Non-related species that inhabit similar environments and mimic each other. Ecological equivalents.In ecology, a niche is the match of a species to a particular environmental situation. It explains how an organism or population responds to the distribution of resources and competitors (for example , by increasing when resources are plentiful and when predators, parasites and pathogens are scarce) and how these same factors are modified in turn. Grinnell (1917, 1924, 1928) was amongst the first to use the word niche. He regarded the niche as an organism's functional role and location in its culture. The niche was essentially considered by Grinnell to be a behavioural unit, although he also stressed it as the ultimate distributional unit (thereby having physical environment spatial characteristics). For example, ecological equivalents have similar types of adaptations but belong to different taxonomic groups; American desert succulents are cacti, while euphorbias are those of the African desert.
The correct answer is option (B) If both assertion and reason are true and the reason is not the correct explanation of the assertion.
Note: Ecological niche is a term used to define the location of a species in an ecosystem, both the variety of conditions that are required for the species to persist and its ecological role in the ecosystem. All the interactions between a species and the biotic and abiotic ecosystem are replaced by the ecological niche, which is therefore a very simple and fundamental ecological term.