Biology Ch 15 Evolution & Chapter 16 Understanding Key Concepts
Identify the five conditions that may cause evolution in population
Any exception to the Hardy-Weinberg equilibrium can result in evolution
State several inferences about evolution that are supported by fossil evidence
-Different organisms lived at different times -Today's organisms are different from the past -Fossils found in adjacent layers are more like each other than fossils in deep layers -When and where different organisms existed
Compare the three main causes of variation in the genotypes of organisms
1) Mutation A random change in a gene that is passed on to offspring 2) Recombination The reshuffling of genes in a diploid individual 3) The random pairing of gametes Occurs because each organism produces large number of gametes so the union of a particular pair is by chance
Identify the five conditions that are necessary for Hardy-Weinberg genetic equilibrium
1. No net mutations occur; that is, the alleles remain the same 2. Individuals neither enter nor leave the population 3. The population is large (ideally, infinitely large) 4. Individuals mate randomly 5. Selection does not occur
Explain how the meanings of the words differ: Allopatric speciation and sympatric speciation
Allopatric means populations are separated from a geographic barrier no longer experience gene flow between them while sympatric is when two sub populations become reproductively isolated within the same geographic area
Explain how the meanings of the words differ: Allele frequency and phenotypic frequency
An allele frequency is determined by dividing the number of a certain allele by the total number of alleles of all types in the populations while a phenotypic frequency is equal to the number of individuals with a particular phenotype divided by the total number of individuals in a population
Describe evidence from biogeography that species evolve adaptations to their environments
Australian mammals have pouches for carrying their young demonstrating these animals evolved in isolation on the continent
Explain why antibiotics are not consistently effective against infections of bacteria
Because the bacteria is adapting to antibiotics which means many can fight them off
Contrast Cuvier's catastrophic with Lyell's uniformitarianism
Catastrophic is the idea geologic catastrophes caused the extinction of large groups at certain points while uniformitarianism is that certain geologic process changing earths surface in the past continue to work in the same ways
Summarize the examples of convergent and divergent evolution seen in Caribbean lizards
Convergent evolution- the population split into several groups, each of which is adapted to a specific habitat, they eventually become a separate species Divergent evolution- the islands lizard population increases & the lizards exhibit hereditary variation in toe pad size and leg length
Define the biological process of evolution
Evolution is the idea that new types of organisms developed from preexisting types of organisms & heritable change in characteristics within a population from one generation to the next
Relate the roles of adaptation and fitness in the theory of natural selection
Fitness= Overproduction Struggle to Survive & Differential Reproduction= Adaptation
Explain how the meanings of the words differ: Punctuated equilibrium and gradualism
Gradualism is the idea that speciation occurs at a regular gradual rate while punctuated equilibrium is the idea is is a rapid change
Describe an example of coevolution
Humans have developed antibiotics to kill disease causing bacteria, as antibiotic use has increased, many bacteria have developed to resist this medicine
Explain how the meanings of the words differ: Immigration and emigration
Immigration is the movement of individuals into a population while emigration is out
Summarize the hypothesis of punctuated equilibrium as it relates to the rate of speciation
In speciation, some scientists believe there were bursts relative to the geologic time scale this would mean species arise abruptly and differ noticeably from the root species
List examples of how mating could be non random in a population
Individuals may select a mate that has traits similar to their own traits this mate would probably have similar genes the selection of a mate based off similar traits is assortive mating non random mating affects which alleles will be combined within individuals but it does not affect overall allele frequencies within a population
Explain how biological molecules indicate relatedness between species
It means they are most likely to develop from the same ancestor; using phylogeny scientists interpret how close the biological relationships are on trees
Explain why the biological species concept cannot be used to identify fossil organisms
It says that a species is a population of organisms that can successfully interbreed but not with other groups, this doesn't provide a definition for the extinct since the reproductive compatibility cannot be tested
Identify several factors that could limit the growth of populations
Limited resources, predators, and diseases
Contrast natural selection with sexual selection
Natural selection is when an organism is well adapted to its environment it will more successfully survive and reproduce while sexual selection is when individuals are more likely to survive based off their traits to attract a mate
List the steps of reasoning that Darwin gave to explain the process of natural selection
Overproduction- Each species produces more individuals than can survive to maturity Genetic Variation- The individuals of a population may differ in traits Struggle to Survive- Individuals must compete with each other for limited resources Differential Reproduction- Individuals that have certain traits are more likely to survive and reproduce than individuals that lack those traits
Identify which type of selection is happening when a population's bell curve narrows over time
Stabilizing selection
Explain how the meanings of the words differ: Stabilizing selections and disruptive selection
Stabilizing selection is when individuals with the average form of a trait have the highest fitness while disruptive is when individuals with extreme variation of a trait have greater fitness than individuals with the average form of a trait
Identify an example of a vestigial structure
The human tailbone is made up of vertebrae that resembles an animals tail & pelvic bones go human bones and the human appendix
Describe how the finch species of the Galápagos Islands illustrate descent with modification
The islands are home to 13 different species of finches, each has a beak adapted for certain food Darwin predicting they all developed from a few finches and flew over