Concept explainers
To explain: The evidence that incomplete lineage sorting (ILS) has affected DNA variation in humans, chimpanzees, and gorillas.
Introduction: Incomplete lineage sorting is a factor that makes it difficult to determine the phylogenetic relations between the radiation species. Radiation species are those species that descended from a common ancestor in a short time period. ILS has chances to be common between the commonly related species.
Explanation of Solution
Incomplete lineage sorting is said to occur when a phylogenetic tree developed using a single gene that has differences compared to the tree developed for population or species level. ILS can come as a problematic cause for determining phylogenies because of its increased frequencies. Studies have shown common ancestry between the humans, chimpanzees, and the gorillas. Molecular studies show that ILS has a significant effect on the DNA variation of these species. ILS has caused polymorphism to inherit in two or more species that are descended from the same common ancestor. For example, studies have shown a significant relation between six alleles of humans and 4 alleles of chimpanzees of the same gene at “major histocompatibility” loci A and B. These two-locus are found in both the species and indicate that these loci have arose the method of gene duplication in their common ancestor before
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