Upgrade to remove ads
Only $35.99/year

GBio 153 Chapter 22

Terms in this set (28)

On the Bahamian island of Andros, mosquitofish populations live in various, now-isolated, freshwater ponds that were once united. Currently, some predator-rich ponds have mosquitofish that can swim in short, fast bursts; other predator-poor ponds have mosquitofish that can swim continuously for a long time. When placed together in the same body of water, the two kinds of female mosquitofish exhibit exclusive breeding preferences.What is the best way to promote fusion between two related populations of mosquitofish, one of which lives in a predator-rich pond, and the other of which lives in a predator-poor pond?
Build a canal linking the two ponds that permits free movement of mosquitofish, but not of predators.
Which of the following activities occurs first in order to begin speciation?
interruption of gene flow between two populations
Mechanism of macroevolution works by
multiple acts of speciation on an ancestral organism.
"Conventional wisdom holds that the development of separate species happens quickly, most often when populations become separated by a geographical barrier." This is called ________ speciation. "Even if these groups meet again and manage to mate before diverging too far from one another, their offspring will be unfit and die out." This is described as hybrid ________.
allopatric; breakdown
The most likely explanation for the recent decline in cichlid species diversity in Lake Victoria is
fusion
A species is a member of a group called a population,
whose members have the ability to interbreed and produce viable, fertile offspring.
How can reproductive barriers form between sympatric populations while their members stay in contact with them?
increased polyploidy
Which of these should decline in hybrid zones where reinforcement is occurring?
gene flow between distinct gene pools
In the ocean, on either side of the Isthmus of Panama, are 30 species of snapping shrimp; some are shallow-water species, and others are adapted to deep water. There are 15 species on the Pacific side and 15 different species on the Atlantic side. The Isthmus of Panama started rising about 10 million years ago.In Figure 22.1, the isthmus separates the Pacific Ocean on the left (side A) from the Atlantic Ocean on the right (side B). The seawater on either side of the isthmus is separated into five depth habitats (1-5), with 1 being the shallowest.Figure 22.1There are currently two large, permanent bridges that span the Panama Canal. The bridges are about 8 miles apart. If snapping shrimp avoid swimming at night and avoid swimming under shadows, then what do these bridges represent for the snapping shrimp?
geographic barriers
Which of the following reproductive types of isolation illustrates postzygotic barriers?
hybrid breakdown
The phylogenetic species concept defines a species as
the smallest group of individuals that share a common ancestor.
Which of the following statements about species, as defined by the biological species concept, is (are) correct?
I.Biological species are defined by reproductive isolation.
II.Biological species are the models used for grouping extinct forms of life.
III.The biological species is the largest unit of population in which successful interbreeding is
possible.
I and III
Among known plant species, which of these are the two most commonly occurring phenomena that have led to the origin of new species?
1. allopatric speciation2. sympatric speciation3. sexual selection4. polyploidy
2 and 4
In a hypothetical situation, a certain species of flea feeds only on pronghorn antelopes. In rangelands of the western United States, pronghorns and cattle often associate with one another. If some of these fleas develop a strong preference for cattle blood and mate only with other fleas that prefer cattle blood, then over time which of these should occur, if the host mammal can be considered as the fleas' habitat?1. reproductive isolation2. sympatric speciation3. habitat isolation4. prezygotic barriers
1 through 4
There is still some controversy among biologists about whether Neanderthals should be placed within the same species as modern humans or into a separate species of their own. Most DNA sequence data analyzed so far indicate that there was probably little or no gene flow between Neanderthals and Homo sapiens. Which species concept is most applicable in this example?
phylogenetic
Which of the following criteria used in classification is the most easily evaluated by the observer?
morphology
Bird guides once listed the myrtle warbler and Audubon's warbler as distinct species. Recently, these birds have been reclassified as eastern and western forms of a single species, the yellow-rumped warbler. Which of the following pieces of evidence, if true, would be cause for this reclassification?
The two forms interbreed often in nature, and their offspring survive and reproduce well.
Please use the following information to answer the question(s) below.In the ocean, on either side of the Isthmus of Panama, are 30 species of snapping shrimp; some are shallow-water species, and others are adapted to deep water. There are 15 species on the Pacific side and 15 different species on the Atlantic side. The Isthmus of Panama started rising about 10 million years ago.In Figure 22.1, the isthmus separates the Pacific Ocean on the left (side A) from the Atlantic Ocean on the right (side B). The seawater on either side of the isthmus is separated into five depth habitats (1-5), with 1 being the shallowest.Figure 22.1In which habitat should one find snapping shrimp most closely related to shrimp that live in habitat A4?
B4
Dogs (Canis lupus familiaris) and gray wolves (Canis lupus) can interbreed to produce viable, fertile offspring. These species shared a common ancestor recently (in geologic time) and have a high degree of genetic similarity, although their anatomies vary widely. Judging from this evidence, which two species concepts are most likely to place dogs and wolves together into a single species?
biological and phylogenetic
In a hypothetical situation, the National Park Service, which administers Grand Canyon National Park in Arizona, builds a footbridge over the Colorado River at the bottom of the canyon. The footbridge permits migration to occur between populations of two closely related antelope squirrels. Previously, one type of squirrel had been restricted to the terrain south of the river, and the other type had been restricted to terrain on the north side of the river. Immediately before and 10 years after the bridge's completion, researchers collected 10 antelope squirrels from both sides of the river, took blood samples, and collected frequencies of alleles unique to the two types of antelope squirrels (see the graphs in Figures 22.2 and 22.3). The data in these graphs indicate that:
two-way migration of squirrels occurred across the bridge, but without hybridization.
In the ocean, on either side of the Isthmus of Panama, are 30 species of snapping shrimp; some are shallow-water species, and others are adapted to deep water. There are 15 species on the Pacific side and 15 different species on the Atlantic side. The Isthmus of Panama started rising about 10 million years ago. The oceans were completely separated by the isthmus about 3 million years ago.Why should deepwater shrimp on different sides of the isthmus have diverged from each other earlier than shallow-water shrimp?
They have been geographically isolated from each other for a longer time.
A hybrid zone is properly defined as
an area where mating occurs between members of two closely related species, producing viable offspring.
More species are found on subdivided areas due to
geographic isolation.
Two species of frogs belonging to the same genus occasionally mate, but the offspring fail to develop and hatch. What is the mechanism for keeping the two frog species separate?
the postzygotic barrier called hybrid inviability
Sexual selection in cichlids occurs by female mate choice and results in reproductive isolation when
under normal light, each species prefers males of their own species.
You are confronted with a box of preserved grasshoppers of various species that are new to science and have not been described. Your assignment is to separate them into species. There is no accompanying information as to where or when they were collected. Which species concept will you have to use?
morphological
Rocky Mountain juniper (Juniperus scopulorum) and one-seeded juniper (J. monosperma) have overlapping ranges. If pollen grains (which contain sperm cells) from one species are unable to germinate and make pollen tubes on female ovules (which contain egg cells) of the other species, then which of these terms are applicable?
1 and 2
Which mechanism would reverse speciation?
increased gene flow
Sets found in the same folder