Suppose that a group of male pied flycatchers migrated from a region where there were no collared flycatchers to a region where both species were present. Assuming events like this are very rare, which of the following scenarios is least likely?
A) The frequency of hybrid offspring would increase.
B) Migrant pied males would produce fewer offspring than would resident pied males.
C) Pied females would rarely mate with collared males.
D) Migrant males would mate with collared females more often than with pied females.
E) The frequency of hybrid offspring would decrease.
Answer: E
The Origin of Species
- Plant species A has a diploid number of 12. Plant species B has a diploid number of 16. A new species, C, arises as an allopolyploid from A and B. The diploid number for species C would probably be
- Which of the following factors would not contribute to allopatric speciation?
- Bird guides once listed the myrtle warbler and Audubon's warbler as distinct species. Recently, these birds have been classified 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?
- According to the punctuated equilibria model,
- Males of different species of the fruit fly Drosophila that live in the same parts of the Hawaiian Islands have different elaborate courtship rituals. These rituals involve fighting other males and making stylized movements that attract females. What type of reproductive isolation does this represent?
- The largest unit within which gene flow can readily occur is a
- 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.
- On the volcanic, equatorial West African island of Sao Tomé, two species of fruit fly exist. Drosophila yakuba inhabits the island's lowlands, and is also found on the African mainland, located about 200 miles away. At higher elevations, and only on Sao Tomé, is found the very closely related Drosophila santomea. The two species can hybridize, though male hybrids are sterile. A hybrid zone exists at middle elevations, though hybrids there are greatly outnumbered by D. santomea. Studies of the two species' nuclear genomes reveal that D. yakuba on the island is more closely related to mainland D. yakuba than to D. santomea (2n = 4 in both species). Sao Tomé rose from the Atlantic Ocean about 14 million years ago.
- In order for speciation to occur, what must be true?
- Which of the following statements about speciation is correct?
- Speciation Speciation A) occurs at such a slow pace that no one has ever observed the emergence of new species. B) occurs only by the accumulation of genetic change over vast expanses of time. C) must begin with the geographic isolation of a small, frontier population. D) and microevolution are synonymous. E) can involve changes to a single gene.
- According to the concept of punctuated equilibrium,
- According to the concept of punctuated equilibrium, the "sudden" appearance of a new species in the fossil record means that
- A narrow hybrid zone separates the toad species Bombina bombina and Bombina variegata. What is true of those alleles that are unique to the parental species?
- The most likely explanation for the recent decline in cichlid species diversity in Lake Victoria is
- The most likely explanation for the high rate of sympatric speciation that apparently existed among the cichlids of Lake Victoria in the past is
- Which of these should decline in hybrid zones where reinforcement is occurring?
- A hybrid zone is properly defined as
- The phenomenon of fusion is likely to occur when, after a period of geographic isolation, two populations meet again and
- The origin of a new plant species by hybridization, coupled with accidents during nuclear division, is an example of
- Beetle pollinators of a particular plant are attracted to its flowers' bright orange color. The beetles not only pollinate the flowers, but they mate while inside of the flowers. A mutant version of the plant with red flowers becomes more common with the passage of time. A particular variant of the beetle prefers the red flowers to the orange flowers. Over time, these two beetle variants diverge from each other to such an extent that interbreeding is no longer possible. What kind of speciation has occurred in this example, and what has driven it?
- Among known plant species, which of these have been the two most commonly occurring phenomena that have led to the origin of new species?
- The difference between geographic isolation and habitat differentiation is the
- Two closely related populations of mice have been separated for many generations by a river. Climatic change causes the river to dry up, thereby bringing the mice populations back into contact in a zone of overlap. Which of the following is not a possible outcome when they meet?