Question

Most people experience increased infant mortalities at high altitudes. Explain how a mutation that allows normal levels of infant survival at high altitudes would spread through a human population that had just begun living high in the mountains. Make sure to include the concepts of variation, selection, and inheritance in your explanation.

Answer 1

Most people experience increased infant mortalities at high altitudes due to the inability of the mother to provide sufficient oxygen to the developing fetus but now variation in the DNA sequence in the people that lives at higher altitudes like in Tibetans allow normal level of infant survival at high altitudes.

This variation occurred in the EPAS1 gene in the Tibetan population that is responsible for delivering oxygen more efficiently to the fetus. This nucleotide variation is also present in low landers of Beijing but natural selection selected the variant gene in Tibetan people because they require this mutated gene for their survival.

So the population passed this variant gene in next-generation, therefore, inheritance allowed the spreading of the mutated gene to the next generation therefore by natural selection and inheritance a mutated gene spread through a human population that had just begun living high in the mountains.