The natural geographical distribution of kangaroos is limited to the Australian continent because
Show Hint
- abiotic factors determine the distribution
- dispersal is limited by accessibility to other continents
- kangaroos have not selected habitats in other continents
- predators limit the distribution in other continents
The Correct Option is B
Solution and Explanation
Kangaroos evolved in Australia and became geographically isolated due to ocean barriers. They cannot naturally disperse to other continents because they cannot cross large water bodies.
Step 2: Analyze options.
(A) Incorrect — abiotic factors do influence distributions, but this does not explain continent-level restriction.
(B) Correct — limited dispersal due to Australia's isolation explains their confinement.
(C) Incorrect — animals do not “choose” continents; physical barriers matter more.
(D) Incorrect — predators do not prevent natural distribution across continents.
Step 3: Conclusion.
Kangaroos remain restricted to Australia mainly due to geographic isolation and limited dispersal ability.
Top Questions on Ecology
Two important characteristics for estimating any population of animals and plants are \(\underline{\hspace{2cm}}\) and \(\underline{\hspace{2cm}}\) of individuals.
- Match List-I with List-II
\[\begin{array}{|l|l|} \hline \textbf{List-I} & \textbf{List-II} \\ \hline \text{(A). Population size} & \text{(I). It refers to how many individuals reside in a particular area} \\ \hline \text{(B). Population density} & \text{(II). It yields helpful information about how species interact with each other} \\ \hline \text{(C). Population distribution} & \text{(III). It represents the total number of individuals in a habitat} \\ \hline \text{(D). Population dispersion} & \text{(IV). It describes how individuals of a species are spread out, whether they live in close proximity} \\ \hline \text{to each other or far apart, or clustered into groups} \\ \hline \end{array}\]
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Choose the most appropriate answer from the options given below: - Match LIST-I with LIST-II
\begin{tabularx}{0.9\textwidth}{|l|X|l|X|} \hline \multicolumn{2}{|c|}{LIST-I} & \multicolumn{2}{c|}{LIST-II}
\multicolumn{2}{|c|}{Interaction Type} & \multicolumn{2}{c|}{Example}
\hline A. & Mutualism & I. & Chlorella vulgaris and Diatoms
B. & Commensalism & II. & Termites and Trichonympha
C. & Proto-cooperation & III. & Intestine of Man and Entamoeba coli
D. & Antibiosis & IV. & Adamsia pallia and hermit crab
\hline \end{tabularx}
Choose the most appropriate answer from the options given below:
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