What are the reasons that you can think of for the arthropods to constitute the largest group of the animal kingdom?
Arthropods constitute the largest phylum of Animalia, with over two-thirds of all named species on earth. Several features contribute to their success and diversity.
The chitinous exoskeleton provides protection and support to the body. The presence of jointed appendages allows for diverse locomotion and adaptation to various habitats. The body is segmented into head, thorax and abdomen, enabling functional specialization of body regions.
Arthropods possess diverse respiratory organs including gills, book gills, book lungs and tracheal system, allowing them to inhabit different environments. They have well-developed sensory organs like antennae, compound and simple eyes, and statocysts. Fertilisation is usually internal and development may be direct or indirect, contributing to their reproductive success.
Explanation
The textbook describes various characteristic features of arthropods in Section 4.2.7. While it states that arthropods are the largest phylum with over two-thirds of all named species, students need to logically connect the described features to explain their success. Key features mentioned include: chitinous exoskeleton, jointed appendages, segmented body, diverse respiratory organs, sensory organs, internal fertilisation, and varied development patterns. These features collectively enable arthropods to adapt to diverse environments and survive successfully.
Solution Steps
Step 1: Identify the statement from context that arthropods are the largest phylum with over two-thirds of all named species
Step 2: List the characteristic features of arthropods from the provided text
Step 3: Logically connect these features to explain their adaptability and success as a group