1) Gregor Mendel was important because he added to Darwin's theory of natural selection by providing more evidence. Darwin knew what happened and what was the result of a species that evolved with a trait but not how. Mendel by using his pea plants was able to display the laws of inheritance.
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3) The first example of variation is point mutation. This occurs when one singe base pair changes. An example of this is when the mutation inactivates the gene for signaling the muscle to begin growing like in a smaller dog. The second example of variation is insertion. Sometimes a base pair inserts itself into the genes causing a change. An example of this is in wrinkled peas, wrinkled peas are caused by an 800 base pair insertion that changes the phenotype and genetic make up. The third example of this is a gene copy number. This is when each gene copies due to a division error. An example of this chimpanzees because they only eat green plants they contain only one gene for starch digestion but somewhere along the line of evolution we now can have up to 10 of these genes. The fourth example of variation is duplication. Duplication is when the sequences for the same base-pair genes are repeated up to 8 times or more. An example of duplication is pigs and their colouring. The colouring of pigs with dark spots are a result of copying mistakes when sequences were duplicated and lost a base as a result. The fifth and last example of variation is regulatory changes. Regulatory changes are mutations that controls when and where genes are activated. This can shift a whole organism by altering the formation of entire body parts in the early developmental stages. An example of this is the drastic evolution from the teosinte plant to the modern corn stalk.
4) Evo-devo is the study in biology which is specific to changes in important developmental genes and their effect in evolution.
5) The migration of humans relates to the the development of being lactose tolerant because that mutation probably occurred on the path out of Africa. The mutation probably arose in the middle east when our ancestors first settled there because they depended on milk-producing animals as their herd. This mutation led them to produce lactase and could continue drinking milk.
Notes:
The other stuff we learned from the Journey of man video was that the Y chromosome is the best place to look for genetic markers. This is because it is easier to spot mutations that don't change, unlike the X- chromosomes that tend to change a lot. Our ancestors also most likely left Africa in the middle of an ice age because this ice age caused the climate to be dry and they most likely suffered in a large drought so they had to move to places with water. Populations also developed lighter skin to absorb the essential uv radiation in cold places where they are less exposed and need to synthesize vitamin D. In reverse other people have darker skin to protect them from the harsh uv radiation in those areas. Central Asian DNA is also important to the study of races because in central asia the major population shift took place so that some people migrated to Europe and East asia. The modern day Chuchki tribe are the living survivors of generations that migrated from central asia to america, yet some stayed in eastern siberia. Bergmann's and Allen's rule is when there is a very cold climate and humans have adapted to have a smaller surface area and be short to preserve as much heat as possible and so that it won't be lost. They along with this adaption have to keep a very active life so they don't freeze. These gives answers to why are ancestors could be successful in cold climates. The first americans also arrived 15,000 years ago through land exposed due to the ice age in eastern siberia.
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