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