Bio 112 Exam 1

family

division of order in the taxonomic classification system

class

division of phylum in the taxonomic classification system

What does the biological species concept use as the primary criterion for determining species boundaries? a. Gene Flow b. Niche differences c. Morphological similiarity d. Geographic isolation

a. Gene Flow

postzygotic barriers

reproductive isolation mechanism that occurs after zygote formation

reproductive isolation

situation that occurs when a species is reproductively independent from other species; this may be brought about by behavior, location, or reproductive barriers

allopatric speciation

speciation that occurs via geographic separation

adaptive radiation

speciation when one species radiates out to form several other species

population genetics

study of how selective forces change a population through changes in allele and genotypic frequencies

binomial nomenclature

system of two-part scientific names for an organism, which includes genus and species names

Cladistics

system to organize homologous traits to describe phylogenies

molecular systematics

technique using molecular evidence to identify phylogenetic relationships

Macroevolution

broader scale evolutionary changes that scientists see over paleontological time

Analogy

characteristic that is similar between organisms by convergent evolution, not due to the same evolutionary path

order

class division in the taxonomic classification system

Aneuploidy

condition of a cell having an extra chromosome or missing a chromosome for its species

Reinforcement

continued speciation divergence between two related species due to low fitness of hybrids between them

Systematics

field of organizing and classifying organisms based on evolutionary relationships

Species

group of populations that interbreed and produce fertile offspring

Variation

genetic differences among individuals in a population

branch point

node on a phylogenetic tree where a single lineage splits into distinct new ones

Hybrid

offspring of two closely related individuals, not of the same species

Allele

one of a number of different forms of a gene

monophyletic group

organisms that share a single ancestor

homologous structures

parallel structures in diverse organisms that have a common ancestor

Phenotype

physical characteristics of an organism

species-area relationship

the relationship between area surveyed and number of species encountered; typically measured by incrementally increasing the area of a survey and determining the cumulative numbers of species

Biodiversity

the variety of a biological system, typically conceived as the number of species, but also applying to genes, biochemistry, and ecosystems

chemical diversity

the variety of metabolic compounds in an ecosystem

T or F. Genetic drift is aptly named because it causes allele frequencies to drift up OR down randomly

True

T or F. Cactus plants needed to protect themselves so they grew thorns.

False

alelle frequency

(also, gene frequency) rate at which a specific allele appears within a population

Phylum

kingdom division in the taxonomic classification system

sister taxa

two lineages that diverged from the same branch point

behavioral isolation

type of reproductive isolation that occurs when a specific behavior or lack of one prevents reproduction from taking place

ecosystem diversity

variety of ecosystems

genetic diversity

variety of genes in a species or other taxonomic group or ecosystem, the term can refer to allelic diversity or genome-wide diversity

Important points about evolution

1. Individuals don't evolve 2. Natural selection works with heritable traits 3. Evolution does not have a goal

What evidence do we have for evolution?

1. Vastness of geologic time 2.Extinction changes the species present over time 3. Transitional features of older and younger species 4. Vestigial traits are evidence of change through time 5. Species can be observed changing today 6. Similar species in the same geographic area 7. Related species share homologies 8. Formation of New species from preexisting species can be observed

Which of the following groups could be identified using the biological species concept? a. extinct dinosaurs b. maple trees c. bacteria d. polar bears

B/D

T or F. Giraffe necks grew longer over evolutionary time because giraffes stretched their necks to reach leave higher in the treetops.

False

T or F. I adapted to the cold temperature in the classroom.

False

T or F. Rose plants needed to protect themselves so evolved sharp thorns.

False

Speciation

Formation of new species

Homology

Similarity in characteristics resulting from a shared ancestry.

Genotype

The combination of alleles that you inherited from your parents

Taxonomy

The science of classifying organisms

biodiversity hotspots

a concept originated by Norman Myers to describe a geographical region with a large number of endemic species and a large percentage of degraded habitat

vestigial structures

a physical structure present in an organism but that has no apparent function and appears to be from a functional structure in a distant ancestor

Taxon

a single level in the taxonomic classification system

endemic species

a species native to one place

Do you think genetic drift would happen more quickly on an island or on the mainland? a. Island b. Mainland

a. Island

Referring to the tree above - which of the following forms a monophyletic group? a. E, F, G b. A, C, F c. B, D d. there are no monophyletic groups in this tree

a. E, F, G

What is an evolutionary adaptation? a. a trait that improves the fitness of its bearer, compared with individuals without the trait b. a trait that changes in response to environmental influences within the individual's lifetime c. the ability of an individual to adjust to its environment d. a trait that an individual wants so that it can survive

a. a trait that improves the fitness of its bearer, compared with individuals without the trait

basal taxon

branch on a phylogenetic tree that has not diverged significantly from the root ancestor

gene pool

all the alleles that the individuals in the population carry

dispersal

allopatric speciation that occurs when a few members of a species move to a new geographical area

Vicariance

allopatric speciation that occurs when something in the environment separates organisms of the same species into separate groups

maximum parsimony

applying the simplest, most obvious way with the least number of steps

hybrid zone

area where two closely related species continue to interact and reproduce, forming hybrids

polytomy

branch on a phylogenetic tree with more than two groups or taxa

Which situation would most likely lead to allopatric speciation? a. A storm causes several large trees to fall down. b. Flood causes the formation of a new lake. c. A mutation causes a new trait to develop. d. An injury causes an organism to seek out a new food source

b. Flood causes the formation of a new lake

Use the figure above to answer the following question. If two species eat a different diet but one of the food sources is eliminated and both species are forced to eat the same foods, what change in the hybrid zone is most likely to occur?

b. Fusion

Which of the following is an example of dispersal? a. A river that fragments a population of rabbits. b. Humming birds flying from the mainland to nest on an island. c. A road that separates one group of deer into two. d. A mountain range that prevents snakes from moving from one side of the mountains to the other.

b. Humming birds flying from the mainland to nest on an island.

Why isn't inbreeding considered an evolutionary process? a. It does not change genotype frequencies. b. It does not change allele frequencies. c. It does not occur often enough to be important in evolution. d. It does not violate the assumptions of the Hardy-Weinberg principle.

b. It does not change allele frequencies.

The phenomenon of fusion is likely to occur when, after a period of geographic isolation, two populations meet again and ________. a. a decreasing number of viable, fertile hybrids is produced over the course of the next 100 generations b. an increasing number of viable, fertile hybrids is produced over the course of the next 100 generations c. no reproduction occurs in the hybrid zone d. there is no way to predict what fusion will cause

b. an increasing number of viable, fertile hybrids is produced over the course of the next 100 generations

Which of the following evolutionary forces can introduce new genetic variation into a population? a. natural selection and genetic drift b. mutation and gene flow c. natural selection and nonrandom mating d. mutation and genetic drift

b. mutation and gene flow

Which type of selection results in greater genetic variance in a population? a. stabilizing selection b. directional selection c. disruptive or diversifying selection

c. disruptive or diversifying selection

Three populations of crickets look very similar, but the males have courtship songs that sound different. What function would this difference in song likely serve if the populations came in contact? a. A temporal reproductive isolating mechanism b. A postzygotic isolating mechanism c. A behavioral reproductive isolating mechanism d. A gametic reproductive isolating mechanism

c. A behavioral reproductive isolating mechanism

When male lions reach sexual maturity, they leave their group in search of a new pride. This can alter the allele frequencies of the population through which of the following mechanisms? a. natural selection b. genetic drift c. gene flow d. random mating

c. gene flow

Microevolution

changes in a population's genetic structure

In plants, violet flower color (V) is dominant over white (v). If p = .8 and q = 0.2 in a population of 500 plants, how many plants would you expect to have violet flowers, and how many would have white flowers? a. 300 violet and 200 white b. 400 violet and 100 white c. 250 violet and 250 white d. 480 violet and 20 white

d. 480 violet and 20 white

Which of the following is an example of vicariance? a. Birds flying to new habitat. b. Lizards riding a log to a new island. c. Whales migrating from the equator towards the south pole. d. A river dividing one group of squirrels into two.

d. A river dividing one group of squirrels into two.

Which of the following situations will lead to natural selection? a. The seeds of two plants land near each other and one grows larger than the other. b. Two types of fish eat the same kind of food, and one is better able to gather food than the other. c. Male lions compete for the right to mate with females, with only one possible winner. d. All of the above.

d. All of the above.

shared ancestral character

describes a characteristic on a phylogenetic tree that is shared by all organisms on the tree

shared derived character

describes a characteristic on a phylogenetic tree that is shared only by a certain clade of organisms

phylogenetic tree

diagram that reflects the evolutionary relationships among organisms or groups of organisms

temporal isolation

differences in breeding schedules that can act as a form of prezygotic barrier leading to reproductive isolation

Gene structure

distribution of the different possible genotypes in a population

genus

division of family in the taxonomic classification system; the first part of the binomial scientific name

Kingdom

domain division in the taxonomic classification system

peer review

evaluation of scientific, academic, or professional work by others working in the same field.

founder effect

event that initiates an allele frequency change in part of the population, which is not typical of the original population

Phylogeny

evolutionary history and relationship of an organism or group of organisms

Megafauna

large animals

punctuated equilibrium

model for rapid speciation that can occur when an event causes a small portion of a population to be cut off from the rest of the population

gradual speciation model

model that shows how species diverge gradually over time in small steps

allopolyploid

polyploidy formed between two related, but separate species

Autopolyploidy

polyploidy formed within a single species

gametic barrier

prezygotic barrier occurring when closely related individuals of different species mate, but differences in their gamete cells (eggs and sperm) prevent fertilization from taking place

divergent evolution

process by which groups of organisms evolve in diverse directions from a common point

convergent evolution

process by which groups of organisms independently evolve to similar forms

natural selection

reproduction of individuals with favorable genetic traits that survive environmental change because of those traits, leading to evolutionary change

prezygotic barriers

reproductive isolation mechanism that occurs before zygote formation

habitat isolation

reproductive isolation resulting when populations of a species move or are moved to a new habitat, taking up residence in a place that no longer overlaps with the other populations of the same species

rooted

single ancestral lineage on a phylogenetic tree to which all organisms represented in the diagram relate

sympatric speciation

speciation that occurs in the same geographic space

Extinction

the disappearance of a species from Earth; local extinction is the disappearance of a species from a region

heterogeneity

the number of ecological niches

extinction rates

the number of species becoming extinct over time

modern synthesis

the overarching evolutionary paradigm that took shape by the 1940s and is generally accepted today