Upgrade to remove ads
Only $35.99/year

Issues in Biology Unit 5

Terms in this set (74)

Explain why the acceptance of evolution by the United States population is so low.
1. Perceived conflicts between professed religious convictions and the theory of evolution
2. Lack of understanding of the basic nature of science
3. Lack of understanding of the theory of evolution
4. Politicization of evolution
State a general definition for the term evolution.
involves cumulative change over time; Cumulative - successive additions or gradual step
Describe cosmic evolution.
The study of the sum total of the many varied developmental and generational changes in the assembly and composition of radiation, matter, and life throughout the history of the Universe.
Describe geological evolution.
The study of the geologic history of Earth, evolution of the continents, oceans, atmosphere, and biosphere.
Describe biological evolution.
The study of the change in inherited traits over successive generations in populations of organisms.
Define population.
All members of the same species within a given space at a given time; Species - group of like organisms that can mate and produce viable offspring
Define gene pool.
All the alleles (genes) found within a population of organisms.
Define biological evolution.
cumulative changes in allele (gene) frequency of a population over time; important point: cumulative change in population characteristics results from cumulative changes in allele (gene) frequencies over time
Identify the smallest unit of life that can undergo biological evolution.
a population
Explain why changes in the characteristics of a population due to environmental factors are not evolutionary in nature.
Changes in the characteristics of a population due to environmental factors are NOT evolutionary in nature because these changes in the characteristics of the population do not involve cumulative changes in allele (gene) frequencies! Examples: Average life expectancy in U.S. in 1900 - 48 years, in 2020 - 78.93 years
Define scientific theory and identify its characteristics.
an explanation of a repeatedly verified natural phenomenon; Based on well-supported hypotheses, Has NOT been proven, but may be disproven, NOT a fact, but an attempt to explain facts (different theories may explain the same facts), Carries much weight in science
Define fact of science.
In science, fact is a confirmed observation.
Distinguish between the fact of evolution and the theories of evolution.
Biological evolution- the characteristics of a population change over time - THIS IS A FACT. In science, theory is an explanation of a repeatedly verified natural phenomenon: Based on well-supported hypotheses, Has NOT been proven; may be disproven, NOT a fact, but an attempt to explain facts, carries much weight in science.
Identify those mechanisms which produce evolution.
mutation, gene flow, nonrandom mating, genetic drift, natural selection
Describe the theory of common descent.
all organisms on Earth today are descendants of a single ancestor that arose in the distant past
Identify the attempts to explain shared characteristics of life.
Cells, DNA, molecules, development, metabolic pathways, etc.
Distinguish between microevolution and macroevolution.
Microevolution is the process by which organisms change in small ways over time. Macroevolution refers to larger evolutionary changes that result in new species.
Define microevolution.
Pattern of evolution in which there is evolutionary change within a population.
Define macroevolution.
Pattern of evolution that produces new species.
Describe the characteristics of microevolution and identify an example.
Characteristics: Due to a change in allele frequency within gene pool, May result in changes in phenotype frequencies, Happens on a small scale, Can be observed over short periods of time
Example: red vs. white eyed fruit flies
Define mutation and describe how mutations function in evolution.
a change in DNA; produces new alleles, the raw material for evolutionary change
Define gene flow and identify an example.
sharing of genes between two populations; ex: green and brown beetles
Define immigration
Moving into a population
Define emigration
Moving out of a population
Define genetic drift, describe its characteristics and identify an example.
random changes in allele frequency within a population; the ratio of one allele to another randomly changes generation to generation; ex: deer dying by chance
Identify the mechanisms of genetic drift
genetic drift reduces genetic variation in populations, which may reduce a population's ability to respond to environmental selective pressures, acts faster and has more drastic results in smaller populations, may contribute to the formation of a new species
What are the bottleneck effect and the founder effect patterns of?
They are patterns of genetic drift.
Describe how the bottleneck effect operates and identify its characteristics as well as an example of the bottleneck effect.
occurs when a population's size is reduced for at least one generation and then recovers, typically reduces a population's genetic variation (the population may not be able to adjust to new selection); ex: northern elephant seals; cheetahs
Describe how the founder effect operates and identify its characteristics as well as an example of the founder effect.
the colonization of an area by a limited number of individuals who, by chance, have different allele frequencies than the parent population, typically produces reduced genetic variation as opposed to the parent population; ex: the amish
Define non-random mating and identify factors which influence non-random mating.
mating that does not occur due to chance; influenced by proximity, phenotype, competition
Describe sexual selection, its characteristics, originator of the theory and examples.
competition between individuals of one sex for the right to mate with the opposite sex; typically involves males (via competition between males and expression of characteristics which attract females); leads to increased fitness (fitness- the ability to transfer genes to the next generation); theory proposed by Charles Darwin in 1871; ex: vivid colors in birds, etc.
Identify factors influencing non-random mating in humans.
phenotype: attractiveness, stature, intelligence, skin color, personality; cultural values; social rules
Define the theory of natural selection.
process by which individuals possessing certain inheritable characteristics of traits have greater survival and reproductive success than individuals lacking such characteristics; the environment "selects" favorable phenotypes; results in a population adapted to the environment
Describe the sequence of mechanisms involved in natural selection within a population.
1. Individuals within a population vary (ex: color, size, shape, etc.)
2. variation among individuals of the population can be passed on to the offspring of the next generation
3. populations produce far more offspring than the environment can support (some live, most die)
4. because more individuals are produced than can survive, members of the population must compete for limited resources among themselves, other species, and the environment
5. some individuals have variations that enable them to survive better than others in the environment (possess greater fitness)
6. reproduction is NOT random (the fittest individuals have a better opportunity to reproduce)
7. advantageous variations become more common in a population
8. results in a population aspirated to its local environment
Who is the originator of the theory of natural selection, published in On the Origin of Species in 1859.
Charles Darwin
Define fitness as it relates to organisms.
the ability of an organism to survive and reproduce within its environment (measured against the fitness of other members of the population living in the same environment); results from adaptation
Define adaptation and identify examples of organism's adaptations.
any characteristic that gives an organism a better chance of survival in its environment (physical and behavioral characteristic)
Who originated the statement survival of the fittest? When?
Herbert Spencer, 1864. Used in Darwin's Origin of Species, 5th ed. 1869.
Identify the basic rules of natural selection.
populations evolve, individuals do not
- Natural selection acts on the level of the individual, but populations are the smallest unit that can evolve
natural selection only works on inheritable variations, not acquired characteristics
natural selection can only work with what it's given
- Variations produced by different genetic mechanisms
natural selection is situational to a given environment in a given time and place
- Environments undergo change
Describe examples of natural selection.
North American English Sparrow phenotypes - Adaptation to temperature. Larger and darker in the north, smaller and lighter in the south.
Describe Dr. Richard Lenski's natural selection experiment (Michigan State University, 1988-present) with Escherichia coli bacteria.
Experiment: Used a single E. coli bacterium to produce 12 separate colonies, Transferred 1% of each colony to a new flask each day, Average 6-7 generations per day (> 58,000 generations), Froze samples every 500 generations for comparison, Observed each population for evidence of evolution
Results: • All 12 colonies evolved: Smaller population densities, Larger cell size, Ability to better exploit glucose, 70% faster growth rate than ancestor strain, 4 colonies' ability to repair DNA decreased, Colony 3 acquired the ability to use citrate as a food source, Research revealed two sequential mutations: Mutation A + Mutation B = Ability to use Citrate as food
Define artificial selection and identify examples of characteristics of organisms that have been artificially selected for.
selective breeding of domesticated animals and plants to increase the frequency of desirable characteristics; ex: modern corn (zea mays); wild v. domestic plants (strawberries, tomatoes, sunflowers, etc.)
Describe Dmitry Belyaev's (1917-1985) fox domestication experiment.
Selected 130 foxes that showed the least fear on a fur farm and allowed them to breed, did the same thing with the next generation, and repeated. After 10 years domestication was successfully achieved.
Define polygenic traits, identify their characteristics and give examples of polygenic traits.
Quantitative traits controlled by more than one pair of alleles w/ contributing and noncontributing alleles, Wide range of phenotypes, Frequency distribution typically resembles a bell-curve, ex: human height, eye color, etc.
Identify and describe the following pattern of natural selection, giving examples: directional selection.
Selection for one extreme phenotype; population evolves in the direction of the preferred extreme; ex: 1848 Manchester, England peppered moth with 99.99% light and 0.01% dark. After industrial revolution, 1895 showed 2% light and 98% dark.
Identify and describe the following pattern of natural selection, giving examples: stabilizing selection.
Selection for the average phenotype; population stabilizes, nearly all the individuals are the same phenotype; ex: amount of eggs in starling birds w/ ideal amount 4-5 eggs. >4 not enough to guarantee survival, <5 is too many to keep warm.
Identify and describe the following pattern of natural selection, giving examples: diversifying selection
Selection for both extreme phenotypes; population diversifies into nearly equal percentages of both extremes; ex: snail coloration in forest = dark, grassland = light.
Define species.
A group of similar organisms that are reproductively isolated from other groups of organisms, Gene flow occurs between members of a species, Gene flow does not occur between members of different species
Define speciation.
origination of new species, Via changes in a population's gene pool allele frequencies due to micro-evolution mechanisms: Mutation, Gene flow, Genetic drift, Non-random mating, Natural selection
Describe the mechanism of allopatric speciation and identify examples.
Origin of new species in a population separated by a geographic barrier, ex: kaibab squirrel on north side of Grand Canyon, abert squirrel on south side of Grand Canyon.
Identify the steps of allopatric speciation.
1. Original population
2. Geographic barrier separates population, Gene flow is prevented
3. Variations are produced in both populations via: Mutations, Gene flow (other populations), Genetic drift, Non-random mating, Natural selection
4. Over time, two distinct species originate, reproductively isolated from each other
Describe the mechanism of sympatric speciation and identify examples.
Origin of species in a population not subjected to geographic isolation, ex: Cichlid fish species in Lake Victoria, in east Africa, approximately 450 species, Species developed from a common ancestor, Adapted to unique food and habitats
Identify the steps of sympatric speciation.
1. Original population
2. Variations are produced in both populations via: Mutations, Gene flow (other populations), Genetic drift (exploiting new habitats), Non-random mating, Natural selection
3. Divergence between isolated gene pools leads to new species
Identify science's theory of human evolution.
Human evolution is the lengthy process of change by which people originated from apelike ancestors. Scientific evidence shows that the physical and behavioral traits shared by all people originated from apelike ancestors and evolved over a period of approximately six million years.
Identify and describe the following biological evidence of evolution: evolution of resistance
In order for resistance to develop, a novel genetic characteristic must occur in the population, and it must persist and expand by providing a replicative advantage; comes in the form of Antibiotic resistance, Antiviral resistance, and Pesticide resistance
Identify and describe the following biological evidence of evolution: camouflage
a form of mimicry in which a species appears similar to its surroundings
Identify and describe the following geological evidence of evolution: age of Earth
Earth is old: 4.6 billion years, provides time required for evolution to occurred
ex: rock dating
Identify and describe the following geological evidence of evolution: environmental change
Environments change by natural processes: Patterns of life followed geological changes
ex: Grand Canyon
Identify and describe the following geological evidence of evolution: continental drift.
Alfred Wegener, 1915: Pangaea - supercontinent, 200 million years ago, Drifted apart to form modern continents
Evidence: Fit of continents, Fossil similarities, Geological similarities, Modern GPS readings
Environments changed as continents drifted Populations adapted or perished
Define fossil and identify the evidence of evolution related to fossils.
any evidence of a past organism that has been preserved in the Earth's crust
Provide evidence of: Past organisms, Diversity of life, Gradual change over time, Succession of life forms, Transition between groups of organisms
Define relative dating of fossils.
dating technique used to determine the age of a fossil relative to fossils in other layers of rock, cannot determine the actual age of the fossil
Define absolute dating of fossils.
dating techniques used to calculate the actual age of fossils
Distinguish between relative and absolute dating.
relative compares fossils to the age of other fossils in other layers of rock, absolute dating uses dating techniques to find the exact age of a fossil without comparison
Describe how radioactive decay is utilized in the absolute dating of fossils.
Radioactive elements decay at a consistent rate to non-radioactive forms (parent daughter)
Define half-life and, when given data, be able to calculate the half-life of a radioactive element.
the time required for one half of the radioactive element to decay, the age of a fossil can be determined by calculating the length of time over which radioactive decay has been occurring within the fossil
drawback: testing destroys part of the fossil
Let's say you start with 16 grams of 11Be. Wait 13.81 seconds, and you'll have 8 grams left; the rest will have decayed to Boron 11. Another 13.81 seconds go by, and you're left with 4 grams of 11Be; 13.81 seconds more, and you have 2 grams.
Define transitional fossil and identify examples.
Fossils that document evolutionary transition; ex: Archaeopteryx - Intermediate between bird and dinosaur discovered in 1859
Define biogeography and describe how it provides evidence for evolution.
the study of the geographical distribution of organisms
Evidence that related forms evolved from a common ancestor that diversified as they spread into other accessible areas
Identify the following as anatomical evidence of evolution and state examples: vestigial structures.
Organism structures that have no apparent function, Evidence of ancestral structures
ex: Humans- Muscles for wiggling ears, Boa constrictors- Hip bones and rudimentary hind legs, Blind cave fish- Nonfunctional eyes, Whale- Rudimentary hind legs
Identify the following as anatomical evidence of evolution and state examples: homologous structures.
Body parts of different organisms, possessing different functions but similar structure, Evidence of common ancestry
Ex: human and monkey hands
Identify the following as anatomical evidence of evolution and state examples: analogous structures.
Structures similar in function, but not origination. Produced by convergent evolution: the independent evolution of similar structures in unrelated populations, produced as different populations adapt to similar environments
Identify the following as anatomical evidence of evolution and state examples: structural imperfections.
Evidence that evolution is non-directional
Example: Vertebrate eyes, Blind spot, Photoreceptors are in the posterior of the retina
Identify biochemical evidences of evolution.
All life is carbon based
All life uses the same genetic molecules - DNA, RNA• Life possesses similar chemical processes: Photosynthesis, Cellular respiration, Enzymatic reactions
Similar organisms have similar genetic codes: Humans and chimpanzees share nearly identical genes, 98.4% identical gene sequences
Identify embryological evidences of evolution.
An early stage of vertebrate development, All vertebrate embryos share common features: Eye spot, pharyngeal gill pouches, Notochord, Tail, Developmental similarities reflect descent from a common ancestor
Are religion and science compatible?
Yes.
Other sets by this creator