As per Malthus the doubling time for population of a region is:

The correct answer is: 25 years.

Thomas Robert Malthus was an English cleric and scholar, influential in the fields of political economy and demography. He is best known for his theory on population growth, which he articulated in his work, "An Essay on the Principle of Population." Malthus argued that population growth would eventually outpace food production, leading to widespread famine and poverty unless controlled by moral restraint or other checks.

Key Points

Malthusian Theory:

• Exponential Growth:
  • Malthus proposed that population grows exponentially (doubling at regular intervals), while food production increases arithmetically (adding a constant amount each period).
• Doubling Time:
  • According to Malthus, the doubling time for a population is the period it takes for the population to double in size. He estimated this to be about 25 years under ideal conditions.
• Preventive Checks:
  • To avoid the dire consequences of unchecked population growth, Malthus advocated for preventive checks such as moral restraint, delayed marriage, and celibacy.
• Positive Checks:
  • If preventive checks are not practiced, Malthus warned that positive checks like famine, disease, and war would inevitably reduce the population to sustainable levels.

Additional Information

• Criticism of Malthusian Theory:
  • Many critics argue that Malthus did not foresee technological advancements that would significantly increase food production, such as the Green Revolution.
  • Others believe Malthus underestimated human innovation in improving agricultural practices and resource management.
• Relevance Today:
  • While some aspects of Malthus's theory have been disproven or mitigated by technological progress, concerns about overpopulation and resource depletion remain relevant in discussions about sustainability and environmental impact.