A) A vampire bat shares food with a sibling who is starving, increasing the sibling’s survival chance by 40%. The cost to the donor is a 10% reduction in its own survival. The donor and recipient are full siblings (i.e. they share the same mother and father). Does this food-sharing behavior satisfy Hamilton’s Rule, and is it likely to be favored? (Need to show calculations to receive full credit) B) Now consider a scenario where the same bat is sharing food with a starving grandparent, increasing the grandparent’s survival chance by 40%. The cost to the donor remains a 10% reduction in its own survival. The relatedness coefficient between the donor and grandparent is r=0.25. Does this food-sharing behavior satisfy Hamilton’s Rule, and is it likely to be favored? (Need to show calculations to receive full credit)

Part 1 – Multiple Choice/Fill-In/True or False/Matching Questions.

A population of beetles is being studied, and the following life table summarizes the survivorship and fecundity data: Age (x) Survivorship (lx​) Fecundity (mx​) 0-1 1.0 0 1-2 0.6 1.0 2-3 0.3 1.5 3-4 0.1 0.5 A) Using the life table, calculate the net reproductive rate (R0​) (Need to show calculations to receive full credit). B) Determine whether the population is growing, shrinking, or stable.

The level of ecological organization that focuses on a single living individual is the [organism] level, while the level that examines groups of the same species living in the same area is the [population] level.

A) A team of ecologists is studying a population of snails in a marsh. During the first sampling, they capture and mark 120 snails before releasing them back into the population. A week later, they recapture 150 snails, 30 of which are marked. Calculate the size of the snail population. (Need to show calculations to receive full credit). B) After carefully observing the recaptured animals, the researchers discovered that 10% of the marked snails actually lost their marks during the study period. Adjust the population estimate to account for this mark loss. Hint: The true number of marked snails in the second sample (R′) can be recalculated as: R′=R/(1−Mark Loss Rate). (Need to show calculations to receive full credit).

Which of the following best describes a species’ realized niche?

Which of the following scenarios best illustrates optimal foraging in the presence of predation risk?

Which of the following traits is most characteristic of an r-selected population?

Match the abiotic factors with their influence on aquatic biomes:

You are given the following data on population densities for two herbivores, Species X and Species Y, in an experimental plot with varying abundances of the same plant species: Plant Abundance (biomass) Species X Density (ind/km²) Species Y Density (ind/km²) Low 5 15 Medium 10 20 High 18 10 A. Based on the data, what might be a reason for the decrease in Species Y density at high plant abundance? B. What ecological concept could explain the contrasting densities of Species X and Y at high plant abundance?