Exponential Growth Phase

When the number of immigration and births is more than emigration and deaths, the growth curve of the population will show an exponential phase. This means that the population will experience rapid and continuous growth over time.

Key Points:
- Immigration refers to the movement of individuals from one country to another for the purpose of permanently residing there.
- Births refer to the number of individuals being born within a population.
- Emigration refers to the movement of individuals out of a country to permanently reside in another.
- Deaths refer to the number of individuals dying within a population.

Explanation:
When the number of immigration and births exceeds the number of emigration and deaths, the population experiences a positive net migration rate and a positive natural increase rate. This leads to an increase in the total population size, which is reflected in an exponential growth phase on the population growth curve.

During the exponential phase, the population grows at an accelerating rate. This occurs because the number of individuals being added to the population through immigration and births is greater than the number of individuals being lost through emigration and deaths. As a result, the population size increases rapidly, leading to a steep upward curve on the growth graph.

The exponential growth phase is characterized by a doubling of the population size within a relatively short period of time. This is due to the compounding effect of population growth, where the larger the population becomes, the more individuals are available for reproduction and immigration, leading to even faster growth rates.

This phase can continue until certain limiting factors, such as resource availability or environmental constraints, begin to exert pressure on the population. At this point, the growth may start to slow down and eventually reach a steady phase or enter a declining phase if the limiting factors become severe enough.

In summary, when immigration and births outnumber emigration and deaths, the population undergoes exponential growth, leading to a rapid increase in population size over time.

Exponential phase because it represents the drastic birth rate