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A study of altruistic behavior among ground squirrels in Canada found that surrogate mothers were only likely to adopt orphaned pups if the babies were related to her. Researchers were able to take into account the degree of relatedness, the number of pups the mother already had, as well as the survival probability of the littler after increasing its size, and they found that females would only adopt orphaned pups if Hamilton’s Rule were satisfied (rB>C, where B is the benefit to the recipient, C is the cost to the altruist, and r is the coefficient of relatedness). Since B an C are independent of the relationship between the recipient of the altruist, only relate ness was a factor in determining whether or not the mother would adopt the orphaned pup. This is an example of 

_______ is the enzyme found in retroviruses that produce DNA from an RNA template.

The table provides information on two populations, Population 1 on the left and Population 2 on the right, in 2 years, 1980 and 2010. The first row has column headers from left to right: Year, Allele uppercase R and Allele lowercase r for Population 1, and Allele uppercase R and Allele lowercase r for Population 2. The data in the next two rows are as follows, from left to right: Row 2: 1980, Population 1: Allele uppercase R, 0.3; Allele lowercase r, 0.7. Population 2: Allele uppercase R, 0.37; Allele lowercase r, 0.63. Row 3: 2010, Population 1: Allele uppercase R, 0.0; Allele lowercase r, 1.0. Population 2: Allele uppercase R, 0.75; Allele lowercase r, 0.25. The table shows the changes in allele frequencies of a specific gene in two populations of randomly mating small mammals after 30 years. The populations inhabit adjacent equatorial islands that have similar topography and climate. Which of the following is the most reliable conclusion that can be drawn from analysis of the data above?

Evolutionary fitness is measured by

In a transformation experiment, a sample of E. coli bacteria was mixed with a plasmid containing the gene for resistance to the antibiotic ampicillin (ampr). Plasmid was not added to a second sample. Samples were plated on nutrient agar plates, some of which were supplemented with the antibiotic ampicillin. The results of E. coli growth are summarized below. The shaded area represents extensive growth of bacteria; dots represent individual colonies of bacteria. Wild type E. coli are plated on plates 1 and 2, and E. coli with plasmid containing the ampicillin resistance gene is plated on plates 3 and 4. Plate 1 has no ampicillin,and is shaded representing extensive growth of bacteria. Plate 2 has ampicillin and is white with no colonies. Plate 3 has no ampicillin and is shaded representing extensive growth of bacteria. Plate 4 has ampicillin and has a dozen dots representing individual colonies of bacteria. Which of the following best explains why there is no growth on plate II?

The y-axis is labeled annual primary production in grams of carbon per square meter from zero to one hundred twenty, in increments of forty. There is a scatter plot with a best fit line. The best fit line starts at approximately two months with ten grams of carbon per square meter, and ends at ten months at around one-hundred grams of carbon per square meter. In the Arctic Ocean, the predominant primary producers are phytoplankton. Phytoplankton are consumed by zooplankton, which in turn are eaten by codfish. In years when there is more open water (less ice coverage), there are more zooplankton and fish than in years with less open water (more ice coverage). Based on the graph above, the difference is most likely because

Evolutionary traits marked along the branches across the top. From the base, a single line extends to the right toward a branch point. The left branch leads upward to taxon A, and the right branch continues upward, passing through a blue dot labeled Large jaws, then reaches another branch point. The left branch from this point leads upward to taxon C, and the right branch continues upward, passing through a blue dot labeled Stripes, then reaches another branch point. The left branch from this point leads upward to taxon B, and the right branch continues upward, passing through a blue dot labeled Short antenna, then reaches another branch point. The left branch from this point continues to taxon B, and the right branch continues upward, passing through a blue dot labeled Darker color before ending at taxon D. Which organism(s) on this cladogram do NOT have short antenna? (Select all that apply.)

When scientists refer to the “environment,” which of the following features are included? (Select all that apply.)

Between every trophic level there is an energy loss of approximately ____%.

 Two curves are displayed. A dashed black line represents the Original population, forming a single bell-shaped curve in the center. A solid pink line with pink shading underneath represents the Population after selection, forming two distinct peaks on the left and right sides of the original peak with a valley between them. This graph depicts _______ selection.