Hunting reduced the population of northern elephant seals to as few as 20 individuals at the end of the 19th century. their population has since rebounded to over 50,000, but they have much less genetic variation than a population of southern elephant seals that was not so intensely hunted. how is the lack of genetic variation related to the hunting episodes of the 1800's?

The 20 original seals had only a few remaining genes from the past generation. When they had offspring a select amount of those genes were passed down. This continued to happen as the seals reproduced limiting the seals genes.

The answer is A) Genetic drift occurred: the few individuals left behind were the seals that passed on that specific gene pool.

1. Mutations in protein-coding genes and regulatory DNA contribute to evolution if the organism carrying them survives and_c. reproduce. Mutations in a_a. gene lead to different effects. For example, a mutation may change the _h. function of the protein or the protein will no longer be produced.

2. Mutations within a_i. regulatory sequence may lead to major changes in_g. body form, for example, if a Hox gene is affected. Moreover, if a transposable element inserts here, it may lead to a decreased or increased_d. protein production. This may impact the organism and if passed on to the offspring, become_e. inherited. The result of these events may eventually lead to increased fitness and the formation of new species.

Explanation:

Mutations can be defined as genetic changes (nucleotide changes) in the genome sequence of an organism. Mutations can be beneficial, neutral or deleterious (depending on their effects on the adaptive fitness of the individual). Mutations that occur in the somatic (body cells) will not be inherited, whereas mutations in the germinal (gamete) cells can be passed on to the next generations. Moreover, Hox genes are major developmental regulators involved in a wide variety of aspects of animal development. In consequence, changes in the expression level of Hox genes caused, for example, through 1-mutations of their regulatory sequences, such as promoter sequences, or 2-the insertion of transposable elements, may lead to conspicuous phenotypic changes by affecting protein production. Eventually, these mutations may confer an adaptive advantage.