Recombination and Gene Distance
Recombination refers to the process by which genetic material is exchanged between two homologous chromosomes during meiosis. This process results in the formation of new combinations of alleles, which contributes to genetic diversity within a population. The frequency of recombination between genes on the same chromosome can be used as a measure of the distance between these genes.

Alfred Sturtevant's Contribution
Alfred Sturtevant, an American geneticist, made significant contributions to the understanding of recombination and gene mapping. In the early 20th century, Sturtevant conducted experiments with the fruit fly Drosophila melanogaster under the guidance of T.H. Morgan. He observed that the frequency of recombination between two genes on the same chromosome was proportional to the physical distance between them.

Sturtevant's Experiment and Results
Sturtevant conducted a series of experiments in which he crossed fruit flies with different combinations of traits controlled by genes located on the same chromosome. By analyzing the offspring, he was able to determine the frequency of recombination between these genes. Sturtevant found that the frequency of recombination was higher between genes that were physically farther apart on the chromosome and lower between genes that were closer together.

Sturtevant's Explanation
Sturtevant proposed that the distance between genes on a chromosome determines the likelihood of recombination occurring between them. Genes that are far apart have a higher chance of undergoing recombination during meiosis, as there is more physical space for the exchange of genetic material. On the other hand, genes that are close together on the chromosome are less likely to undergo recombination, as they are more likely to be inherited together as a unit.

Significance of Sturtevant's Work
Sturtevant's discovery of the relationship between recombination frequency and gene distance paved the way for gene mapping. By determining the frequency of recombination between different genes, scientists can estimate the relative distances between these genes on a chromosome. This information is crucial for understanding the organization of genes within a chromosome and for identifying the locations of specific genes.

In conclusion, Alfred Sturtevant's experiments with fruit flies demonstrated that the frequency of recombination between genes on the same chromosome is related to the physical distance between these genes. This discovery provided a valuable tool for geneticists to map genes and understand their organization within chromosomes.