BIO 1020 - Exam 1

What theory states that all life shares a common ancestor?

theory of common descent

What is an animal called that lives nowhere else but a special region?

endemic

Who proposed mechanisms for how natural selection actually worked which had not been done before?

Darwin

Who described all living things known to his world and assumed they were fixed and immutable?

Aristotle

What is a term that describes that living things could be assigned a hierarchical position on this metaphorical ladder that would represent their degree of perfection?

scala naturae

Who thought that forms of life had changed and proposed that human origins came from sea creatures?

Anaximander

Anaximander developed the first concept of forms transitioning from what to what?

ancestor to descendant

What says that persons have a fixed role in life and one’s stations does not change?

Chain of Being

In the Chain of Being, who is at the universal top?

divine

In the Chain of Being, who is at the earthly top?

royalty

What is the mechanism that explains how biological evolution changes species over time?

natural selection

What was the ship that Darwin visited the Galapagos Islands on for five years?

The Beagle

In what original writing did Darwin publish his thoughts in?

The Origin of Species

Darwin’s insight from the islands said that each island had a slight what that changes certain species from each other?

variations

In what essay did Malthus explain his Point of Crisis Theory?

“Essay on the Principle of Population”

What describes that human population growth can exceed the resources necessary to support them?

Point of Crisis

Animals produce offspring that tend to have less advantageous forms of the traits and will die. These offspring are referred to as what kind of offspring?

missing offspring

What describes that traits you use a lot become more important to survival?

inheritance of acquired characteristics

What describes more used traits being maintained by future generations while disused traits disappear?

use or disused

What is measured as the number of offspring produced?

evolutionary fitness

What refers to a trait or characteristics that increases fitness?

adaptation

What describes the fact that a trait not under selection now may later become useful and heritable?

context-dependent

Traits that do not affect an organism’s ability to leave offspring are considered what?

\-neither decrease or increase survival

neutral variation

Evolutionary theory is considered ( ), which means that it has withstood challenges of application, alternative hypothesis, and has not been falsified.

robust

What kind of selection is controlled by breeders/farmers over nature?

artificial selection

What is the process of adapting wild plants and animals for human use?

domestication

What gives us records of the course of life through time?

\-found in the ground

fossils

The gaps in fossil records are known as what?

missing links

What are structures that may have different appearances and functions but are derived from the same body part in a common ancestor?

homologous structures

What are structures that may function the same but do not share common ancestry?

\-insect and bird wings, for example

analogous structure

What type of structures have no apparent function, but resemble structures their ancestors possessed?

vestigial structures

What kind of evolution describes similar forms having evolved in different, isolated areas because of similar selective pressures in similar environments?

convergent evolution

In what kind of evolution do populations change?

\-results from any process that changes in the genetic composition of a population

microevolution

major __evolutionary__ change in which the evolution of whole __taxonomic__ groups change over long periods of time

macroevolution

What is the study of properties of genes in a population?

population genetics

What is the occurrence of different forms among the members of a population or colony, or in the life cycle of an individual __organism?__

polymorphism

What is it called when alleles are present in 100% of the population?

fixation

What is an allele especially present in homozygotes that is so harmful that it is selected against?

deleterious alleles

What is the model population that is NOT undergoing evolutionary change?

\-determines that the starting and ending frequencies of an allele in a population remain the same across all generations if certain assumptions are met

Hardy-Weinberg Equilibrium

The dominant allele has a frequency designated to what?

p

The recessive allele has a frequency designated to what?

q

What is the ultimate source of genetic variation and an agent of microevolutionary change?

mutation

What is the likelihood that a gene will be altered by a new mutation?

mutation rate

What is the agent of microevolutionary change that is described as the movement of alleles from one population to another?

gene flow

What are the two types of nonrandom mating?

assortative and disassortative mating

In what kind of mating do phenotypically similar individuals mate and increases the proportion of homozygous individuals?

assortative mating

In which kind of mating do phenotypically different individuals mate which produces an excess of heterozygotes?

disassortative mating

Which agent of microevolutionary change describes a smaller population drifting out of a bigger population and causing the alleles to change?

genetic drift

What are the two types of genetic drift?

founder effect and genetic bottleneck

Which type of genetic drift is due to few individuals from a larger and more diverse population FOUNDing a new population?

\-the new population is less diverse than old population

founder effect

Which type of genetic drift is when a population is greatly reduced in size, limiting the genetic diversity of the species?

genetic bottleneck

What are the three modes of natural selection?

disruptive, directional, and stabilizing

What are ways in which natural selection can affect the distribution of attributes in a population?

modes of natural selection

Which mode of natural selection acts to eliminate one extreme and often occurs in nature when the environment changes?

directional selection

Which mode of natural selection acts to eliminate intermediate types?

\-EX: in one population there can be two very different beak sizes that are used for two types of bird seeds

disruptive selection

Which mode of natural selection acts to eliminate both extremes and makes intermediate more common by eliminating extremes?

EX: babies with intermediate birth weights are usually healthier than premature babies or overweight babies

stabilizing selection

What is the change in allele frequencies within the same population?

microevolution

What is the change in species from ancestor to descendant?

macroevolution

What are groups of actually or potentially interbreeding natural populations which are reproductively isolated from other such groups?

species

What is described as members of different species not mating with each other or producing fertile offspring?

reproductive isolation

What are individuals in a certain species that look different than the other members but are still able to produce offspring together?

subspecies

What are reproductive isolating mechanisms where no conception occurs and no zygote occurs?

prezygotic mechanisms

What are reproductive isolating mechanisms where a hybrid zygote forms between two different biological species but the fate of the zygote is usually limited?

postzygotic mechanisms

In what type of isolation are two similar species separated from one another by a geographic barrier, such as river or mountain range?

geographic isolation

In what type of isolation do geographic ranges overlap but different species utilize different parts of the habitat?

\-EX: lions and tigers

ecological evolution

In what type of isolation does certain animal behavior preclude inappropriate species pairings?

\-EX: species-specific courtship behavior

behavioral isolation

What kind of species avoid mating with members of the wrong species in a variety of ways including visual signals, sound production, and chemical and electrical signals?

sympatric signals

What kind of isolation describes different species occurring in the same geographic range, use the same habitat, but aren’t sexually active at the same time of year?

\-EX: species-specific mating season

temporal isolation

What type of isolation described reproductive anatomy of different species being incompatible?

\-EX: species-specific reproductive anatomy

mechanical isolation

What type of isolation are sperm and eggs of different species released at the same time of year and the same location, but only certain eggs and sperm are compatible in certain species?

gametic isolation

What is it called when one ancestral species becomes divided into two descendant species?

cladogenesis

If two species are geographically close to each, their features will

differentiate

What describes two species appearing very similar when they are far away from each other?

allopatry

natural barrier separates species and the population physically moves apart

vicariance

populations of species move to new geographic locality but not because of physical barrier

dispersal

one species splits into two at a single locality, w/o the two new species ever having been geographically separated

sympatric speciation

the heritable condition of possessing more than two complete sets if chromosomes

\-think of sympatric speciation

polyploidy

closely related species that have recently evolved from a common ancestor by adapting to different parts of the environment

\-exposed to new habitat

adaptive radiation

an evolutionary change that occurs when two similar species inhabit the same environment

\-natural selection in each species favors those individuals that use resources not used by the other species

character displacement

What pace of evolution is described as accumulation of small changes over time?

\-lots of intermediate forms

gradualism

What are the two paces of evolution?

gradualism and punctuated

What pace of evolution describes long periods of stasis followed by rapid change?

\-most species are static and changes the same (static)

punctuated equilibrium

the scientific approaches related to classifying the diversity of organisms, both living and extinct, in accordance with evolutionary principles

systematics

assigning scientific names to species

\-helps scientists talk in common language

taxonomy

Who created the binomial system?

\-established hierarchal system of nomenclature

Linnaeus

What is the binomial name comprised of?

Genus and species

What are the hierarchal names of nomenclature?

\-(K, P, C, O, F, G, S)

kingdom, phylum, class, order, genus, species

similarity that is inherited from the most recent common ancestor of an entire group

derived characteristics

similarity that arose prior to the common ancestor of the group

ancestral characteristic

systematic method for reconstructing evolutionary history (phylogeny)

cladistics

organisms all sharing the same derived characteristics are grouped into the same what?

clade

a table that defines characteristics and traits between different species to compare and contrast

character state table

refers to the concept that the simplest explanation in systematics is the best explanation

\-least number of steps in evolution is best

principle of parsimony

defines a species as members of populations that actually or potentially interbreed in nature, not according to similarity of appearance

biological species concept

species is a population or set of populations characterized by one or more shared derived characters

phylogenetic species concept

a type of speciation in which biological populations are physically isolated by an extrinsic barrier and evolve intrinsic (genetic) reproductive isolation

allopatric speciation

an allele for which all members of the population under study are homozygous, so that no other alleles for this locus exist in the population

fixed allele

the combination of all the genes (including alleles) present in a reproducing population or species

gene pool

describes the case in which the heterozygous genotype has a higher relative fitness than either the homozygous dominant or homozygous recessive genotype

heterozygous advantage

the __offspring__ of two plants or animals of different species or varieties, such as a __mule__ (a hybrid of a __donkey__ and a horse)

hybrid