Answer:
The mechanism responsible for the changes in fish size between generation 1 and generation 100 are mutation, genetic drift, and gene flow.
Explanation:
What is mutation?
An alteration in the nucleic acid sequence of an organism's, virus's, or extrachromosomal DNA is referred to as a mutation. DNA or RNA can be found in the viral genome.
Genetic drift.
Genetic drift is the arbitrary change in the frequency of a gene variant in a population. Gene variations may totally vanish due to genetic drift, which would limit genetic diversity.
Gene flow.
Gene flow is the exchange of genetic information between populations. Two populations can be regarded as a single effective population if the rate of gene flow is high enough for them to have similar allele frequencies.
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