He used the frequency of recombination between gene pairs on the same chromosome, as a measure of the distance between genes and mapped their position on the chromosome.
Detailed Answer :
Alfred Sturtevant used the recombination frequency between gene pairs as a measure of physical distance between genes and ‘mapped’ their position on the chromosome. This process of mapping the gene positions was termed as gene mapping, which are used today for genome sequencing projects as in Human Genome Project.
