Answers to Figure Legend Questions

FIGURE 8.3 A proximate explanation for glucose aversion could describe how in cockroaches that exhibit this behavior, glucose activates taste neurons that in other individuals are activated only by bitter substances.

FIGURE 8.5 Yes, the pie charts for the deer mouse and oldfield mouse each have a solid color (tan for the deer mouse, blue for the oldfield mouse), indicating that 100% of the genome of each mouse is composed of markers specific to its species. For the F₁ hybrids, 50% of the genome is from deer mice (as indicated by the tan half of the pie chart) and 50% of the genome is from oldfield mice (as indicated by the blue half of the pie chart). Backcross individuals represent offspring between F₁ hybrids (50% deer mouse genome and 50% oldfield mouse genome) and deer mice (100% deer mouse genome). Thus, we would expect that on average, 75% of their genome would be from deer mice and 25% of their genome would be from oldfield mice—and, as expected, the pie chart for backcross individuals is 75% tan in color and 25% blue in color.

FIGURE 8.6 Under conditions like those in which the relationship between net energy gained and foraging effort was estimated, you could test whether the effort lizards invested in acquiring food was similar to that which would maximize their net energy gained.

FIGURE 8.10 When wolves arrive, the probability that a female is found in grassland decreases whereas the probability a female is found in conifer forest increases; when wolves depart, the reverse is true. Similar patterns are observed for males, but males are less likely to change their behavior in response to the arrival of wolves than are females.

FIGURE 8.15 In the first control, the tails of birds were not altered; results from this control can be compared to results from experimental treatments in which the tail lengths of birds were either shortened or lengthened. The second control (in which a portion of the tail was removed and then glued back on) was included so that Andersson could determine whether cutting a bird's tail had unintended effects.

FIGURE 8.21 This benefit cannot be compared directly to the cost shown in the figure because the benefit is in terms of food intake per hour, while the cost is in terms of increased flying times. To make this comparison you would need to use a common currency, such as the amount of energy gained from the increased food intake versus the amount of energy used during the increased flying times.

FIGURE 8.23 In the absence of wasps, laying eggs on food containing 6% alcohol causes larval survival to drop by about 18% (from 90% in food without alcohol to 72% in food with 6% alcohol). In the presence of wasps, larval survival increases by about 40% (from 10% in food without alcohol to 50% in food with 6% alcohol).

FIGURE 8.24 About 2.9 offspring per nest survived to young adulthood in nests that were not exposed to predator playbacks, whereas about 1.9 offspring per nest survived to young adulthood in nests exposed to predator playbacks. These results indicate that the “cost of fear” was a reduction of 1 offspring per nest.