You Learned How Freshwater Stickleback Populations Have Lost Their Body

question 24

Essay

You learned how freshwater stickleback populations have lost their body armor through positive selection of a low-armor Eda allele, which is found at low frequency in marine populations. Draw (a) a phylogenetic tree that would support the hypothesis that the low-armor phenotype arose once and then spread throughout freshwater populations and (b) a phylogenetic tree that would support the hypothesis that the phenotype arose independently multiple times in freshwater populations.

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Definitions:

Percentage Of Sales

A financial ratio that compares a particular figure or metric to the total sales of a company.

Capital Intensity Ratio

A measure of how much capital is used in the production process, calculated as the ratio of total assets to sales.

Accounts Receivable

The financial obligations customers hold towards a company for products or services that have been served or benefited from, yet are unpaid.

Full Capacity

The maximum level of output that a company can sustain over a long period without increasing maintenance costs or causing wear and tear on its production assets.