The following are effects of food shortage on population size EXCEPT

Analyze the question: We're asked which option is NOT an effect of food shortage on a population. Food is a limiting factor, so we need to find the choice that would not result from scarcity.

Concept: Population size depends on four processes:

• Natality (birth rate) and immigration increase population size.
• Mortality (death rate) and emigration decrease it.

When food becomes scarce, the population is under environmental resistance, so the usual consequences are:

1. Competition: individuals fight over the limited food (A is an effect).
2. Decline in reproduction: poorly fed animals produce fewer offspring, and fewer eggs or young survive (B is an effect).
3. Emigration: individuals move out to look for food elsewhere (C is an effect).
4. Increased mortality: starvation, weakness and disease raise the death rate (E is an effect).

Check the remaining option:

• D. Increase in natality: natality means birth rate. Food shortage lowers it rather than raising it, so this cannot be an effect of food shortage.

Answer: D. increase in natality

Tip: In "EXCEPT" questions, look for the option that goes in the opposite direction to the others. Here, every other option is a negative result of scarcity (competition, fewer births, leaving, deaths), while "increase in natality" is the one that contradicts them. Remember: less food → fewer births, more deaths, more migration out.