WEIT Chap5

The Engine of Evolution

Structure of the chapter

The engine of evolution

evolution without selection (Popo)
Genetic drift: Helps natural selection to build evolution. It is a random fact that in a probalistic situation that an outcome comes more often than the other: For example in a F1 generation one parent having a AB (one A and one B allele) blood type, if the parent has only 1 child it will transmit only one of the two alleles and the other one would be lost. (the parent could have 4 children and the same problem, always randomly give one of the two alleles.)
difference between Nat selec and gen drift Natural selection will select only the useful features whereas the genetic drift is random and can generate useful or harmful changes.
animal and plant breeding (Scott)

evolution is the test tube (Scott)

resistance to drugs and poisons (Ari)

selection in the wild (Ari)

can selection build complexity (Popo)

Vocabulary List

artificial selection =
random = regardless of wether it is useful to the individual
heritability = the genetic basis of a variation
process = a description of how genes that produce better adaptation become more frequent over time, without external will.
mechanism = a process imposed on a population from the outside
fitness = average number of offspring
mutation =
neutral variation = a variation which is neither good or bad
environment =

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