Answer
The improvement in health standards, sanitation, nutrition, and medicine has led to near-exponential growth.
Work Step by Step
A great improvement is recorded in recent years in the overall health status of the individuals because of the advancement in medical and other health sectors. It includes improved sanitation, improved health, and medical procedures. The advancement, in turn, resulted in the decrease in the factors that could contribute to the increased risk of infection or diseases.
This advancement has caused a decrease in the mortality rate. Humans now live with the increased survivorship and fecundity. The survivorship is the fraction of the population that survives, on an average, in a particular environmental condition. Fecundity refers to the ability to produce abundant number of offspring. So, the near-exponential growth has been observed in the past 500 years. However, if the growth does not cease, density-dependent factors may cause a decline in the population.
The population cannot grow exponentially for an indefinite period of time due to limited availability of resources, competition among different organisms, and emergence of new diseases (for which medical facility is not available). So, all these factors tend to limit the population growth beyond the carrying capacity of the environment.
