EVERYDAY SCIENCE

Detailed explanation-1: -Population growth rate is affected by birth rates, death rates, immigration, and emigration. If a population is given unlimited amounts of food, moisture, and oxygen, and other environmental factors, it will show exponential growth.

Detailed explanation-2: -When demographers attempt to forecast changes in the size of a population, they typically focus on four main factors: fertility rates, mortality rates (life expectancy), the initial age profile of the population (whether it is relatively old or relatively young to begin with) and migration.

Detailed explanation-3: -Human population has grown exponentially over the past century. It has done so largely by producing large amounts of food, and learning how to control disease. Ten thousand years ago, when humans first invented agriculture, there were maybe one million humans on the planet.

Detailed explanation-4: -These density-independent factors include food or nutrient limitation, pollutants in the environment, and climate extremes, including seasonal cycles such as monsoons. In addition, catastrophic factors can also impact population growth, such as fires and hurricanes.