Q6.7. In homoeothermic organisms, heat retention efficiency increases as the ratio of surface area to volume decreases. Larger body sizes have a smaller surface area to volume ratio and can retain heat more efficiently than smaller body sizes. Body size in proboscideans (e.g. elephants) is controlled by three genotypes: \begin{tabular}{|l|l|} \hline Genotype & Phenotype \\ \hline EE & Large body size (greater than 4 meters tall) \\ \hline Ee & Intermediate body size (between 2 and 4 meters tall) \\ \hline ee & Small body size (less than 2 meters tall) \\ \hline \end{tabular} A large and diverse population of proboscideans is living in southern France. A significant slowing of thermohaline circulation (an effect of climate change) causes the average ambient temperature of the region to drop by \( 16^{\circ} \mathrm{C} \). Initially, there were equal proportions of \( \mathrm{E} \) and e alleles in the population's gene pool. After the drop in average temperature, all large-bodied proboscideans survived to adulthood and bore of 5 offspring each. \( 70 \% \) of intermediately-sized proboscideans survived to adulthood, and those bore 2 offspring each. \( 50 \% \) of small-bodied proboscideans survived to adulthood, and only bore 1 offspring each. Q 6.7 .1 Make a scatter plot of \( \mathrm{p} \) and \( \mathrm{q} \) over 30 generations. Q 6.7 .2 What mode of selection is going on in this scenario? How do you know? (i.e. How do the relative fitness values compare to one another)? Q 6.7 .3 What phenotype is being favored? What benefits does that phenotype have over the alternative possible phenotypes? Q 6.7 .4 Will this population go to fixation? If so, which allele will become fixed? At which generation did this population reach fixation? (identify the exact generation where the population reached fixation, do not estimate based on the scatterplot you created). What phenotype will all members of the population express after it reaches fixat
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We have a population of proboscideans with three genotypes (EE, Ee, and ee) that determine their body size. The population is initially in equal proportions of E and e alleles. After a drop in temperature, the survival and reproduction rates of each genotype are Show more…
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