36 terms

Ch 14 P2

The evolution of Homo floresiensis is an example of
allopatric speciation
The geographic isolation of a population from other members of the species and the subsequent evolution of reproductive barriers between it and the parent species describes ________ speciation.
Uplift and formation of a mountain range divides a freshwater snail species into two isolated populations. Erosion eventually lowers the mountain range and brings the two populations together again, but when they mate, the resulting hybrids all produce sterile young. This scenario is an example of
allopatric speciation
In which of the following situations would speciation be most likely to occur?
Seven monkeys escape from an amusement park and zoo in South Florida. To everyone's surprise, they establish a small but viable population, coexisting successfully with humans in a partly suburban environment very different from their native African habitat
If H. floresiensis were reunited with H. erectus at a much later date, but the two populations could no longer interbreed, it would be correct to conclude that H. floresiensis
had evolved reproductive barriers
Diane Dodd raised different fruit fly populations on different food sources. She found that after about 40 generations, the evolution of reproductive isolation was under way. The mechanism of evolution responsible for this was
natural selection
Humans are diploid and have 46 chromosomes (or two sets). How many sets of chromosomes are found in each human gamete?
Humans are diploid and have 46 chromosomes. How many chromosomes are found in each human gamete?
_____ is the process by which haploid gametes form a diploid zygote
A particular diploid plant species has 48 chromosomes, or two sets. A mutation occurs and gametes with 48 chromosomes are produced. If self-fertilization occurs, the zygote will have _____ set(s) of chromosomes.
Which of these terms applies to an organism with extra sets of chromosomes?
Mutant tetraploid plants _____.
are unable to interbreed with a diploid plant
Most polyploid plants arise as a result of _____.
Speciation without geographic isolation is called ________ speciation.
Organisms that possess more than two complete sets of chromosomes are said to be
Most polyploid species arise from
the hybridization of two parent species
When a tetraploid flower pollinates a diploid flower of the parental species, the resulting offspring will be
triploid and sterile
Sympatric speciation commonly occurs through ________ in plants, but is more likely to occur through ________ in animals.
polyploidy . . . habitat differentiation and sexual selection
The emergence of many diverse species from a common ancestor is called
adaptive radiation
Which of the following would tend to promote adaptive radiation?
An organism colonizes an isolated area that is habitable but relatively devoid of life
According to island biogeography, what is the relationship between an island's distance from the mainland and the number of species present on the island?
The farther an island is from the mainland, the fewer the number of species found on the island
Why is a new island more hospitable to colonizers than an older island is?
The intensity of both competition and predation is less on the newer island
What is the relationship between colonizing success and the number of species already established on an island?
As the number of established species on an island increases, colonizing success also decreases
The number of species on an island remains relatively constant when _____.
the rate of successful colonization equals the extinction rate
Two bird species overlap in a hybrid zone. They are isolated by a slight difference in the male songs and by the females' tendency to select males with the "correct" song. Hybrid offspring tend to have reduced fertility compared to either of the parent species. What effect might natural selection have in this situation?
Natural selection might favor males with more distinctive calls and/or females that are more "choosy." As a result, the reproductive barrier between the two species could be reinforced
The ________ suggests that speciation occurs in brief spurts.
punctuated equilibrium model
The emergence of a new plant species over a brief period of time, followed by a long period of little change, is consistent with which of the following theories?
punctuated equilibrium
Which of the following descriptions best represents the gradual model of speciation?
Speciation occurs regularly as a result of the accumulation of many small changes.
One of the finest available sequences of fossils shows how horses have changed slowly and by subtle steps from small shrub-browsing ancestors to the large, grass-grazing modern horse. A large number of fossil species have been named, and it is often difficult to decide on the identity of a fossil horse because transitional forms are common. This record of evolution best fits the idea of
the gradual model of speciation
The fossil record shows that for many plant and animal groups, the time between speciation events
the gradual model of speciation
The fossil record shows that for many plant and animal groups, the time between speciation events
varies greatly, but averages 6.5 million years
How are refined sugar and high fructose corn syrup different?
High fructose corn syrup contains more fructose than refined sugar
What, in part, fueled the use of high fructose corn syrup?
High fructose corn syrup is cheaper to produce than refined sugar
Which organ converts fructose to fat?
Approximately how much sugar does the average American consume each year?
90 pounds
Which of the following is in the correct order leading to the development of heart disease?
fat accumulation, insulin resistance, metabolic syndrome