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143 Cards in this Set

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  • Back
Describe the adaptations of the blue-footed boobie
big webbed feet, streamlined shape, large tail, and specialized salt secreting glands
Describe the main ideas that Darwin advanced in his works
species change over time

b. living species have arisen from earlier life forms
Describe Aristotle’s beliefs regarding species and evolution?
perfect and permanant
The eighteenth-century French naturalist Lamarck argued for which mechanism of evolution
Lamarck argued inheritance of acquired characteristice. (remember giraffe example)
Lyell's book Principles of Geology, which Darwin read on board the H.M.S. Beagle, argued for which concept regarding Earth’s geologic history
natural forces gradually change earth's surface and that thses forces are still operating
Who developed a theory of evolution identical to Darwin 's
Alfred Wallace
The unifying theme of biology is
Life evolves and species change over time
“All cells from pre-existing cells”
Today’s advanced cells can be traced back to primitive prokaryotic cells that existed over 3 billion years ago
Basic mechanism of evolution is natural selection - described by Darwin in 1859
What did Darwin discover that led him to suspect that species in the Americas were more closely related to each other than to species elsewhere
The South American fossils he collected were more similar to living South American species
than to fossils from other continents.
Which Greek Philosopher promoted the idea about 2,500 years ago that life arose in water and that simpler forms preceded more complex ones
In the 1700s, __________ raised the possibility that certain fossil forms might be ancient versions of similar living species
The concept of natural selection is best expressed as
survival of the fittest
Describe the assumptions that were part of Darwin 's theory of natural selection.
1. individuals whose inherited traits give them a higher probability of surviving and reproduceing in a given environment tend to leave more offspring than other individuals.

2. this unequal production of offspring will cause favorable traits to accumulate in a population over time
Malthus's essay led Darwin to what generalization that became part of the theory of natural selection
individuals whose traits enable them to better obtain food or escape predators or tolerate physical conditions will survive and reproduce more successfully than individuals without those traits.
Broccoli and cabbages are both descended from the same wild mustard and can still interbreed. The existence of these two vegetables is an example of
artificial selection
Describe the processes of fossil formation
The earliest fossils of life are about ______________ years old
3.5 billion
The first life forms were prokaryotic or eukaryotic
What do we learn from fossil positions in sedimentary strata
The first vertebrates to evolve were
How do fossils provide support for evolution?
Fossils show that life forms have changed over time, and radioactive dating shows the times at which the earlier forms lived
List the different types of evidence that modern species have evolved from prior species
a. molecular biology

b. comparative anatomy

c. comparative embryology

d. biogeography
Describe evidence that vertebrates evolved from a common ancestor
*A) homologous structures
B) the common development of pharyngeal pouches in an embryonic stage
C) similarities in protein structure
Darwin found that Galápagos animals resembled species from what area
South America
Be able to identify homologous structures (like the examples in your text)
arms, forelegs, flippers, and wings
Describe the role of natural selection in evolutionary change
Natural selection produces adaptations that are essential to the survival of populations in changing environments
Give a basic, modern definition of a sexually reproducing species
a group of populations whose members can interbreed and produce fertile offspring
A population is
a group of individuals of the same species in the same place at the same time
Describe the modern evolutionary synthesis
A change in the relative frequencies of alleles in the gene pool of a population is called
In the Hardy-Weinberg equation, homozygous dominant individuals in a population are represented by
What conditions would tend to make the Hardy-Weinberg equation more accurate for predicting the gene frequencies of future generations in a population of a sexually reproducing species?
little gene flow with surrounding populations
The disease phenylketonuria (PKU) is caused by a recessive allele, and one child in 10,000 is born with the disease. Let q represent the frequency of the PKU allele. What is the value of q2
What fraction of the population are carriers for PKU
Genetic drift resulting from a disaster that drastically reduces population size is called
bottleneck effect
A population of 1,000 birds exists on a small Pacific island. Some of the birds are yellow, a characteristic determined by a recessive allele. The others are green, a characteristic determined by a dominant allele. A hurricane on the island kills most of the birds from this population. Only ten remain, and those birds all have yellow feathers. What process has occurred in this population
genetic drift
Thirty people are assigned to live in a spaceship that is exploring other galaxies. The journey will take several hundred years and will be completed by the descendants of these crew members. The gene pool of the population on this ship when it returns is most likely to reflect what process
founder effect
Genetic differences between populations tend to be reduced by
gene flow
The degree of adaptation that can occur in a population is limited by

or fittness
Certain whale species were hunted to near extinction. With a moratorium on hunting them, their population sizes have expanded. What might you expect regarding current populations?
The populations may still be endangered because they may have little remaining genetic variation
Gene diversity is the average percent of gene loci that are ______________ in a population
A graded change in an inherited trait along a geographic continuum is called a
A population is polymorphic for a characteristic if two or more morphs are present in readily noticeable numbers
Is all variation in a population heritable?
In what species would you expect to find individual variation
The genetic variation among individuals in a sexually reproducing population of a plant that does not self-pollinate is the result of
a. gene mutation

b. crossing-over during meiosis

c. independent assortment of chromosomes during meiosis

d. random fertilization
What factors increase the chances that a mutation will significantly affect genetic variation from one generation to the next in most plants and animals
An individual who does not finish all of a prescribed antibiotic is affecting the bacterial population in what way
increasing resistance
Tay-Sachs is inherited as an autosomal recessive allele. Homozygous individuals die within the first few years of life. However, there is some evidence that heterozygous individuals are more resistant to tuberculosis. What does this tell us about the allele for Tay-Sachs
This situation is an example of heterozygote advantage if tuberculosis is present in a population
What factors promote genetic variation in a population
migration of new individuals into the population

mutation of alleles in the population

genetic drift in the population due to random events
In a particular environment, there are no obvious fitness differences among individuals with dark hair and individuals with light hair. The term that best describes this situation is
disruptive selection
Fitness increases when an organism
passes on a greater proportion of it's genes to the next generation
An elk herd is observed over many generations. Most of the full-grown bull elk have antlers of nearly the same size, although a few have antlers that are significantly larger or smaller than this average size. The average antler size remains constant over the generations. What effect probably accounts for this situation
Stabilizing Selection
Long-legged cheetahs are well adapted to catching prey. The ancestor of the cheetah is believed to have had relatively short legs. According to Darwinian views, the evolution of long-legged cheetahs is best explained by
directional selection
A rabbit population consists of animals that are either very dark on top or very light on top. When examining them closely, biologists were surprised to find no rabbit with a medium darkness, intermediate to the two extremes. This is an example of
disruptive selection
Mate-attracting features such as the bright plumage of a male peacock result from
sexual dimorphism
Large antlers in male elk, which are used for battles between males, are a good example of
intrasexual selection
Natural selection and the ability to generate perfection are limited by
selection can only edit existing variations.
chance and natural selection interact.
organisms are limited by historical constraints.
adaptations are often compromises
The primary purpose of the 1831 voyage of the Beagle was to
map the coastline
What was Darwin 's job on board the Beagle (the one that he did not the one that he was originally hired to do)?
captains companion
What term is used to refer to structures that have a similar origin or ancestry even though they may be very different in appearance
What is a mutation
a permanent change in the DNA sequence of a gene
What is the result of natural selection
a change in the gene pool of a population due to differential reproductive success
What is genetic drift
Genetic drift is random changes in the genotype (and phenotype) of a population, without selective pressure. An example is blue eyes in humans: there is no advantage or disadvantage to having blue eyes
In sexually reproducing organisms, the events of __________ do not contribute to an increase in genetic variation
crossing over
Macroevolution is
large scale changes in the history of life
A biological species is defined as a
population or group of populations whose members have the potential to interbreed and
produce fertile offspring
Can the biological species concept be used for organisms that are completely asexual in their reproduction
The ecological species concept identifies species in terms
of their ecological niches
The morphological species concept relies upon
subjective criteria
Taxonomy is the branch of biology concerned with
naming and classifying species and groups them into broader categories
The phylogenetic species concept defines a species as
the smallest group of species that shares a common ancestor
Speciation can occur as a result of reproductive isolation. Reproductive isolation can occur when individuals in two populations of organisms
mate together producing sterile offspring
Which type of reproductive barrier separates a pair of species that could interbreed except that one mates at dusk and the other at dawn?
temporal isolation
Which type of reproductive barrier separates a pair of insect species that could interbreed except that one mates on goldenrod flowers and the other on autumn daisies that blossom at the same time?
habitat isolation
Which type of reproductive barrier separates a pair of moth species that could interbreed except that the females' mating pheromones are not attractive to the males of the other species?
behavioral isolation
What type of reproductive barrier separates two flowering plant species that could interbreed except that one has a deep flower tube and is pollinated by bumblebees, whereas the other has a short, narrow flower tube and is pollinated by honeybees
mechanical isolation
What type of reproductive barrier separates two species that occasionally mate but in whom the sperm do not produce the right enzymes to enter the egg
gametic isolation
Two species that occasionally mate and produce zygotes, but which have incompatible genes that prevent the resulting embryo from developing, are separated by
reduced hybrid viability

or hybrid inviabilty
Two species interbreed occasionally and produce vigorous, fertile hybrids. When the hybrids breed with each other or with either parent species, however, the offspring are feeble or sterile. These species are separated by
hybrid breakdown
Two species that sometimes mate and produce vigorous, sterile offspring are separated by
reduced hybrid fertility

or hybrid sterility
What prevents closely related species from interbreeding even when their ranges overlap
reproductive barrier
Frequently, a group of related species will each have a unique courtship ritual that must be performed correctly for both partners to be willing to mate. Such a ritual constitutes a type of
Give an example of a hybrid that is both vigorous and sterile
The Monterey pine and Bishop's pine inhabit some of the same areas of central California . The Monterey pine releases pollen in February, while the Bishop's pine does so in April. This is an example of __________ isolation
The 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.
The likelihood of allopatric speciation increases when a population is __________ and __________ the broader range of the species
small and isolated
A mountain range divides a freshwater snail species into two isolated populations. Erosion eventually lowers the 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
What kind of situation would be most conducive to rapid speciation
Four circus wolves escape on Long Island. To everyoneʹs surprise, they establish a small but
viable population, coexisting successfully with humans in a partly suburban environment.
The population is physically isolated from other wolves.
Describe the experiments regarding reproductive barriers using fruit flies grown on different kinds of media
Speciation without geographic isolation is called __________ speciation
Sympatric Speciation
Organisms having more than two complete sets of chromosomes are said to be
When a tetraploid plant pollinates a diploid plant of the parental species, what will be the ploidy of the resulting zygote
Sympatric speciation was first discovered by __________ while studying genetic diversity in primroses
de Vries
Most polyploid species arise from
hybridization of two different species
Most polyploid species result from
accidents during cell division
List examples of polyploid plants
oats, potatoes, bananas, peanuts, barley, plums, apples, sugarcane, coffee and wheat
Plant biologists estimate that __________ % of all plant species are polyploids
Most polyploid plants form by
polyploid speciation
is the ancestral diploid wheat plant.
Bread wheat grown widely today is the result of several
Plant geneticists use chemicals to induce meiotic and mitotic errors to try to create
new polyploid plants with special qualities
The emergence of numerous species from a common ancestor that finds itself in a new and diverse environment is called
adaptive radiation
In their 30-year studies of Darwin 's finches, the Grants have discovered that when the ground finch and cactus finch occasionally form hybrids, these hybrids
can only survive during wet years when there are plenty of soft, small seeds.
The fossil record reveals that frequently, speciation occurs
in a relatively short time, perhaps just 50,000 years.
Describe the gradualism model of speciation
The __________ suggests that speciation occurs in spurts.
punctuated equilibrium model
Punctuated equilibrium differs from the gradualism model because in punctuated equilibrium _____
All of the choices are correct.
The emergence of a new plant species over a brief period of time followed by periods of little change would support what theory
punctuated equlibrium theory
The situation in which a structure that evolved in one context is later adapted for another function is called
Give an example of paedomorphosis
A paleontologist who specializes in amphibians notices that there are very few differences in the skull of the adult and juvenile forms of a salamander. This suggests that the salamander exhibits
A study of human evolution compared the features of an adult human skull to the skulls of an adult and infant chimp. At the end of the study, it was clear that the adult human and infant chimp shared many more features than the adult human and adult chimp. This study suggests that humans evolved by the process of
Evolution is a response to interactions between organisms and __________________
A plant with 12 chromosomes produces gametes with 12 chromosomes; if self-fertilization occurs, the zygote would have __________ chromosomes.
What is the nature of the reproductive barrier between a mutant tetraploid plant and its original diploid parents?
Speciation as a result of genetic isolation without geographic isolation is referred to as
sympatric speciation
What do biologist currently believe about the relationship between dinosaurs and birds
By studying fossils in strata from many locations, scientists can learn about _______________
The earliest discovered fossils are __________ dating back to __________ years ago
prokaryotes... 3.5 billion
Plants and animals first became established on land during the
paleozoic era
What era is often called the "Age of Reptiles"?
The earliest known flowering plants date to the
mesozoic... cretaceous
If all of Earth's history were compressed into an hour, humans would first appear about _____ ago
one second ago
The technique called radiometric dating is based on
the measurement of certain radioactive isotopes contained in fossils.
When the continent of Pangaea first split apart, it formed
a northern landmass called Laurasia and a southern landmass called Gondwana.
What evidence suggests that lungfishes evolved while Pangaea was intact?
fossil lungfishes have been found on every continent except Antarctica
When did the Himalaya mountains begin to form
55 million
The continents and seafloors together form a thin outer layer of the Earth called the
Which of the following phenomena can be caused by continental drift? A. mountain formation
B. volcanoes
C. earthquakes
D. the merging and breaking up of continents
Student Response E. All of the choices are correct.
Geologists call the forces within Earth that cause movements of the crust __________
plate tectonics
How many periods of mass extinction have occurred in the last 600 million years?
The process by which species not closely related may come to resemble one another if they live in a similar environment is called ____________
convergent evolution
Structures that evolved from the same structure in an ancestor are
List taxonomic categories in order from most specific to most general?
species, genus, family, order, class, phylum, kingdom, domain
Ever since Darwin , systematics has tried to ___________
classify and determine evolutionary relationships
In the three-domain system, the eukaryotes are represented
only by the Domain Eukarya.
The three-domain system
The three-domain system is different from older classification systems in what way
subdivides the prokaryotes into 2 different domains.
__________ first appeared during the Precambrian era.
The Paleozoic era began approximately __________ million years ago.
The four geologic eras are directly subdivided into
__________ were the dominant plant life during the early Mesozoic era.
cone bearing plants
The Domain Eukarya includes which kingdoms
Protista, Fungi, Plantae, and Animalia. ...
Which of the domains includes prokaryotic cells
bacteria and archaea