22. Evolution and the Origins of Life

Which process ensures that alleles are always found in new combinations?

Natural selection is able to work independently on different genes that are found on the same chromosome because of which process?

Mutations that don’t impact the fitness of an allele can be called?

Gene trees are evolutionary trees that show the evolutionary lineages of specific genes separate from organisms. Below is a gene tree for the genes that code for opsins in humans. Opsins are the light sensitive proteins in the eyes. Humans have four opsins that are active in visual perception: long-wavelength sensitive (LWS or red-sensitive), medium-wavelength sensitive (MWS or green sensitive), short-wavelength sensitive (SWS or blue sensitive), and rhodopsin (RH, not color sensitive). Which mutational process would be most likely to create a gene tree like this?

Which of the following statements about mutations is correct?

Over short time periods, what would you expect to be responsible for creating the most genetic variation in humans?