▶️ Answer/Explanation
(a)(i)
Any one of the following features visible in the diagram identifies it as an insect:
- 3 pairs of legs
- Body divided into three parts (head, thorax, and abdomen)
- One pair of antennae
(a)(ii)
Any one of the following features visible in the diagram identifies it as an arthropod:
- Jointed legs (or jointed appendages)
- Segmented body
Note: An exoskeleton is a feature of arthropods, but strictly speaking, one cannot simply “see” the exoskeleton in a photo in the same way one sees segmentation or joints, though “exoskeleton” is often accepted if implied by the structure. The most distinct visual features are jointed limbs and segments.
(b)(i)
Features: The body is wide and flat, and the leg joints are flattened/wide. The insect looks like a leaf (mimicry).
Importance: This provides camouflage, making it difficult for predators to see or detect the insect. Consequently, it is less likely to be eaten (predation is reduced), increasing its chances to survive and reproduce.
(b)(ii)
In a population of leaf insects there are differences between the individuals. The term for the difference between individuals of the same species is variation.
Individuals that reproduce are able to pass on their alleles (or genes) to the next generation. Over many generations the features of individuals that reproduce will be more common in the population. This process is called natural selection.
(c)
Any three of the following methods can conserve endangered species:
- Monitoring or counting species populations
- Protecting habitats (e.g., creating nature reserves)
- Education (raising awareness)
- Captive breeding programmes (breeding in zoos/labs to release later)
- Seed banks (for plants, though less relevant to insects, it is a general conservation method)
- Reducing hunting, predation, or poaching
- Reducing pollution