A LESSON ON THE NATURE OF SCIENCE INTRODUCTION Dr. Tony Allison is credited with demonstrating the link between the inherited blood disorder sickle cell disease (also called sickle cell anemia) and malaria. His work showed that an infectious disease could act as a selective force to drive human evolution. What inspired him to do this research

He knew that persons living with sickle cell anemia would be most likely to die in places where there was poor medical treatment yet there was the prevalence of the disease. He wanted to know why.

Explanation:  

Dr Allison made a note of his observation. He wanted to correlated frequency of those with sickle cell anemia and the frequency of malaria. He was hoping that he would find a strong correlation.

He began testing for the malaria parasite and the sickle cell trait in young children between the age of 4 months and 4 years. He found that in areas were there were higher incidences of malaria there was also the higher frequency of the allele in these children.

He concluded that persons that carry at least one allele of sickle cell anemia were more likely to survive malaria than those that did not. There was a strong selective pressure on the sickle cell allele in malaria prevalent areas.

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