Natural selection - genetic drift and Hardy-Weinberg

Created March 2020, Offline version here
Video by Paul Anderson, also on his website Bozeman Science.

    One of the main driving forces of evolution is , which is differential reproductive success. The peppered moths of Europe are prime examples when discussing natural selection. The peppered moths are light or dark colored. Before the industrial revolution, the peppered moths thrived, but after the revolution the peppered moths thrived. The five conditions of the Hardy-Weinberg Equilibrium include a large population size, , and no natural selection. A large population of tortoises drastically decreases in size, causing the allele frequencies to change by chance. This mechanism of evolution is an example of . When genetic drift occurs by chance, the ( larger in size and greater in genetic variation), decreases in size and variation and is referred to as the . Genetic drift can cause evolution plummeting the allele frequencies by chance, and it can occur via two factors, . A large flood causes a group of iguanas to get separated from the rest of the iguana population. The separated iguanas are on a different island and begin a new population. This example would lead to a . If human babies are born too small, they experience premature birth complications. If they are born too big, then it poses a risk for the mother and child during delivery. As expected, nature selects for average-size babies. This is an example of . A few factors that can lead to evolution are natural selection, . A population of moose is in Hardy-Weinberg equilibrium. If the dark brown (B) allele frequency is 0.67 and the light brown (b) allele frequency is 0.18, then percent of moose are heterozygotes. The Minckley's cichlid is found in the tropical waters in three sizes -small, medium, and large. The large cichlids are able to dominate and fertilize the female eggs, while the small cichlids pass on their genetics by sneaking up on the spawning females. The medium cichlids are too big to use the tactic and too weak to fight the large cichlids. This cichlid population displays . Scientists have learned a lot about evolution by comparing organisms on various levels. Humans, whales, birds, and lizards all have similar arm bones known as , which indicate a common origin/ancestor.
    The essential characteristics of life that are observed in all organisms include incorporation of the same genetic material ( ), the central dogma ( ) and the production of ATP. We can define as changes within the allele frequency within a gene pool. Bacteria can evolve quickly since their reproduction rate is fast. Consequently, mutations in these organisms make some resistant to certain antibiotics, such as penicillin. The evolution of bacteria over time is a good example of . A pond near the midwest thrives with light green colored bullfrogs. However, runoff from a nearby factory has greatly increased the eutrophication in the pond, leading to the production of dark green algal blooms. The natural selection that is acting upon this new environment and allowing the dark green bullfrogs to thrive is .