Final answer:
Herd immunity is a concept in biology that protects non-vaccinated individuals due to the majority of people being vaccinated. It is similar to a fenced area in Africa where informed farmers obtained healthy grass within the fence by rotating their grazing animals and allowing the fields to lie fallow. Outside the fence, where nomads grazed their animals without planning, the land became barren and devastated.
Step-by-step explanation:
In biology, the concept of herd immunity refers to the protection from infection that non-vaccinated individuals in a population receive because the majority of people around them are vaccinated and immune to the infection. This concept is similar to the fenced area in Africa where informed farmers rotated their grazing animals and allowed the fields to lie fallow, resulting in the growth of grass within the fence. Outside the fence, where nomads grazed their animals without planning, the land became bare and devastated. The concept of herd immunity emphasizes the importance of planning and vaccination to protect a population against infectious diseases.