Exam 3: Evolutionary Change and Adaptation

Imagine that in one portion of their range, black widowbird numbers are declining due to the introduction of a non-native snake that eats their eggs and nestlings. Prior to mating, a male widowbird produces sperm cells through the process of __________. When the sperm fuses with an egg cell, __________ has occurred.

Imagine that in one portion of their range, black widowbird numbers are declining due to the introduction of a non-native snake that eats their eggs and nestlings. In the summer, temperatures in the native range for black widowbirds are exceedingly hot. To cool themselves, the birds undergo a type of panting known as gular fluttering. This leads to evaporative water loss that cools the birds. This cooling is essential for __________.

Which of the following is true about dogs?

Imagine that in one portion of their range, black widowbird numbers are declining due to the introduction of a non-native snake that eats their eggs and nestlings. The last two remaining females in this population disperse to join a different population that is 50 km away. Breeding with males in this new population would introduce new genes and is an example of __________.

The graph below represents the results of an experiment looking at mate preference in female black widowbirds. The researcher used three groups of male birds: one with artificially shortened tails, one with artificially lengthened tails, and the control group with unaltered tail lengths. Black widowbirds can be described as medium-sized birds with orange and white shoulders and showy tail feathers. This is __________.

Imagine that in one portion of their range, black widowbird numbers are declining due to the introduction of a non-native snake that eats their eggs and nestlings. The last two remaining females from the region with the introduced snakes disperse and join another group of widowbirds that are nesting 50 km away. There they find new mates and produce offspring. This group of birds would be considered a(n) __________.

The islands of Hawaii lie approximately 3200 km from the nearest continent and so have been geographically isolated for most of their history. Nearly 800 species of fruit flies have been discovered on these islands, and molecular and anatomical data suggest that the vast majority of these species arose from a single ancestral species that colonized the Hawaiian Islands from eastern Asia. The divergence into multiple different species is an example of __________.

In Chapter 2, you learned about beneficial bacteria that live on our skin and lower the pH, which in turn keeps other disease-causing bacteria in check. This relationship between beneficial bacteria and their human hosts is an example of __________.

The common garter snake is a predator of the rough-skinned newt. These newts produce a potent neurotoxin that is concentrated in their skin, but garter snakes have evolved resistance to this toxin. Over the years, the neurotoxin has become more toxic. How might the toxin have changed over time?

Imagine that in one portion of their range, black widowbird numbers are declining due to the introduction of a non-native snake that eats their eggs and nestlings. The last two remaining females in this population disperse to join a different population that is 50 km away, where they breed with new males. If these females produce only sterile offspring as the result of mating with males in the new population, what type of reproductive isolation does this represent?

A gardener is constantly struggling with the growth of weeds in his perennial flower beds. At the start of the growing season one year, he sprays an herbicide to reduce the number of weeds. Although the herbicide kills many of the weeds, some develop resistance to the herbicide and continue to grow and spread among his flowering plants. After a few years, the gardener decides to stop all herbicide applications. One of the changes that he notices is that the weeds that have resistance to herbicides grow much more slowly and are easily outcompeted by other weeds when no pesticides are sprayed (i.e., the herbicide-susceptible weeds produce more seeds and quickly overtake some of the areas in the garden where the herbicide-resistant weeds had been growing). Based on this information, is herbicide resistance an adaptation in this population?

The process of meiosis produces ____________________.

Naked mole rats live in underground colonies and are very inbred; there is typically no interaction between different colonies or populations. However, every now and again, a "disperser morph" is produced, and this animal eventually leaves his birth colony and finds a different colony where he will likely mate with the queen. This is an example of

Which process must occur after meiosis for successful production of offspring?

The graph below represents the results of an experiment looking at mate preference in female black widowbirds. The researcher used three groups of male birds: one with artificially shortened tails, one with artificially lengthened tails, and the control group with unaltered tail lengths. Although females prefer males with the longest tails, very long tails are typically not found among males in their natural environment. Why might this be the case?

The common garter snake is a predator of the rough-skinned newt. These newts produce a potent neurotoxin that is concentrated in their skin, but garter snakes have evolved resistance to this toxin. The production of toxin by the rough-skinned newts, which deters many predators, is an example of __________.

Imagine that in one portion of their range, black widowbird numbers are declining due to the introduction of a non-native snake that eats their eggs and nestlings. If all the individuals in the threatened population die, this would be described as __________.

Which of the following is an example of an inherited characteristic?

Which of the following is an example of a phenotype?

In the Chiricahua Mountains in Arizona, a species of spider is found in both the woodland areas around streams and in the desert shrub areas. In the woodland areas, these spiders are under constant threat of predation from birds. Because of this, they spend little time in the exposed portion of their sheet webs. However, in the desert areas where birds are less of a threat, spiders constantly forage in the exposed portion of their webs. Offspring of matings between spiders from woodland and desert regions behave more like spiders from the desert habitat, even if they are living in the woodland area. The offspring quickly fall prey to birds, often before they have had a chance to reproduce. Over time, two different species arise. Was this a pre-mating or post-mating barrier?