Consider the following statements: 1. All Echinoderms are not marine

Consider the following statements:

  • 1. All Echinoderms are not marine.
  • 2. Sponges are exclusively marine.
  • 3. Insects are found in all kinds of habitats.
  • 4. Many primates are arboreal.

Which of the statements given above is/are correct ?

1, 3 and 4 only
3 and 4 only
2 and 4 only
3 only
This question was previously asked in
UPSC NDA-1 – 2016
The correct answer is B) 3 and 4 only.
Let’s examine each statement:
1. All Echinoderms are not marine: This statement is incorrect. Echinodermata (which includes starfish, sea urchins, sea cucumbers, brittle stars, and crinoids) is a phylum consisting *entirely* of marine animals. There are no freshwater or terrestrial echinoderms.
2. Sponges are exclusively marine: This statement is incorrect. While the vast majority of sponges (Phylum Porifera) are marine, there are a number of species found in freshwater habitats (e.g., the family Spongillidae).
3. Insects are found in all kinds of habitats: This statement is correct. Insects (Class Insecta) are the most diverse group of animals and have colonized almost every habitat on Earth, including terrestrial, freshwater, and some marine environments (coastal areas, surface films, etc.). They are absent from the open ocean deep sea.
4. Many primates are arboreal: This statement is correct. Arboreal animals live in trees. Many species of primates (like most monkeys and some apes) are well-adapted for life in trees and spend most of their time in forest canopies.
Based on the analysis, statements 3 and 4 are correct.
Echinoderms are known for their radial symmetry (usually pentaradial in adults) and unique water vascular system. Sponges are simple multicellular animals, filter feeders, lacking true tissues and organs. Insects are characterized by a chitinous exoskeleton, a three-part body (head, thorax, and abdomen), three pairs of jointed legs, compound eyes, and typically two pairs of wings. Primates are characterized by traits like relatively large brains, grasping hands and feet, and forward-facing eyes.