Question

1. Populations tend to grow at their intrinsic growth rate initially but then their growth rate slows down. Why is this? Give an example of a real or imaginary species which was just introduced to an island; discuss the population's growth rate over time, giving specific reasons for any changes in growth rate.

Answer 1

At initial population grows at intrinsic rate, because due to less competition between the organisms for resources like , food , shelter etc. As the no of the individual increase , there will be slowing in population growth due to scarcity of resources. This type of growth is known as logistic growth. So a particular ecosystem has specific carrying capacity. That means maximum no of individual can be sustained by that particular ecosystem.

Simple example is yeast , a fungus used to make beverages and bread. Show logistic growth . When yeast put in a test tube , it grows faster due to plenty of food and less competition. As no of yeast increases, there is competition as well as scarcity of food thus limit the growth of yeast . Due to carrying capacity of that system.