Evolution

Question	Answer
Natural Selection	A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.
adaptive radiation	Period of evolutionary change in which groups of organisms form many new species whose adaptations allow them to fill different ecological roles in their communities.
speciation	An evolutionary process in which one species splits into two or more species.
artificial selection	The selective breeding of domesticated plants and animals to encourage the occurrence of desirable traits.
homologous structures	Structures in different species that are similar because of common ancestry.
analogous	Having characteristics that are similar because of convergent evolution, not homology.
convergent evolution	The evolution of similar features in independent evolutionary lineages.
Ecological niche	The specific role a species has in its environment
founder effect	Genetic drift that occurs when a few individuals become isolated from a larger population and form a new population whose gene pool composition is not reflective of that of the original population.
bottleneck effect	Genetic drift that occurs when the size of a population is reduced, as by a natural disaster or human actions. Typically, the surviving population is no longer genetically representative of the original population.
genetic drift	A process in which chance events cause unpredictable fluctuations in allele frequencies from one generation to the next. Effects of genetic drift are most pronounced in small populations.
gene flow	The transfer of alleles from one population to another, resulting from the movement of fertile individuals or their gametes
sexual dimorphism	Differences between the secondary sex characteristics of males and females of the same species.
allopatric speciation	The formation of new species in populations that are geographically isolated from one another.
sympatric speciation	The formation of new species in populations that live in the same geographic area
rooted phylogenetic tree	each node with descendants represents the inferred most recent common ancestor of the descendants, and the edge lengths in some trees may be interpreted as time estimates.
polytomy	In a phylogenetic tree, a branch point from which more than two descendant taxa emerge. A polytomy indicates that the evolutionary relationships between the descendant taxa are not yet clear.
sister taxa	Groups of organisms that share an immediate common ancestor and hence are each other’s closest relatives.
biological species concept	Definition of a species as a group of populations whose members have the potential to interbreed in nature and produce viable, fertile offspring but do not produce viable, fertile offspring with members of other such groups.
macroevolution	Evolutionary change above the species level. Examples of macroevolutionary change include the origin of a new group of organisms through a series of speciation events and the impact of mass extinctions on the diversity of life and its subsequent recovery.
microevolution	Evolutionary change below the species level; change in the allele frequencies in a population over generations.
intersexual selection	A form of natural selection in which individuals of one sex (usually the females) are choosy in selecting their mates from the other sex; also called mate choice.
punctuated equilibria	In the fossil record, long periods of apparent stasis, in which a species undergoes little or no morphological change, interrupted by relatively brief periods of sudden change.
Gradualism	a theory or a tenet assuming that change comes about gradually or that variation is gradual in nature
autopolyploid	An individual that has more than two chromosome sets that are all derived from a single species.
allopolyploid	A fertile individual that has more than two chromosome sets as a result of two different species interbreeding and combining their chromosomes.
heterochrony	Evolutionary change in the timing or rate of an organism’s development.
paedomorphosis	The retention in an adult organism of the juvenile features of its evolutionary ancestors.
homeotic gene	Any of the master regulatory genes that control placement and spatial organization of body parts in animals, plants, and fungi by controlling the developmental fate of groups of cells.
monophyletic	Pertaining to a group of taxa that consists of a common ancestor and all of its descendants. A monophyletic taxon is equivalent to a clade.
paraphyletic	Pertaining to a group of taxa that consists of a common ancestor and some, but not all, of its descendants.
polygenic inheritance	An additive effect of two or more genes on a single phenotypic character.
shared ancestral character	A character, shared by members of a particular clade, that originated in an ancestor that is not a member of that clade.
shared derived character	An evolutionary novelty that is unique to a particular clade.
Carolus Linnaeus	Looked for order in the diversity of life through taxonomy for the greater glory of God. Developed the system of binomial nomenclature (Genus species).
Cuvier - Geologist	Good… Older fossils dissimilar to current life forms From one layer to the next, some species disappeared Bad… Catastrophism
Hutton - Geologist	Hutton – geological features by processes still operating today. Good…. Geological Gradualism
Lyell - Geologist	Principle of Uniformitarianism – mechanisms of change were constant over time.
Hutton + Lyell	“ the same processes are working gradually over long periods of time.”
Jean-Baptiste Lamarck	Use and Disuse + Inheritance Use and Disuse Inheritance
Adaptive Radiation example	Image: 7344cfc7-5ef3-4144-bf3a-8f8bbaa2dca9 (image/jpg)
Theory of Evolution in three words......	Decent With Modification
Geologists and Biologists that came before Darwin	Carolus Linnaeus 1707 – 10 January 1778 Sweedish Botanist, Physicial and Zoologist Jean-Baptiste Lamarck (French Naturalist) (1 August 1744 – 18 December 1829) Hutton (Geologist, uniformitarianism) (1726-1797) Georges Cuvier - Geologist (August 23, 1769 – May 13, 1832) Sir Charles Lyell (Geologist) (14 November 1797 – 22 February 1875) (French Naturalist and Zoologist)
Darwin’s Observations and Inferences Observation 1	members of a population often vary greatly in their traits.
Darwin’s Observations and Inferences Observation 2	Traits are inherited from parents to offspring.
Darwin’s Observations and Inferences Observation 3	All species are capable of producing more offspring than their environment can support.
Darwin’s Observations and Inferences Observation 4	Owing to a lack of food or other resources, many of these offspring do not survive.
Darwin’s Observations and Inferences Inference 1	Individuals whose inherited traits give them a higher probability of surviving and reproducing in a given environment tend to leave more offspring than other individuals
Darwin’s Observations and Inferences Inference 2	This unequal ability of individuals to survive and reproduce will lead to the accumulation of favorable traits in the population over generations.
How long does artificial selection take?	VERY FAST
How long does Natural Selection take?	Very fast (catastrophic pressure) to very slow (natural pressure)
Natural selection works on	individuals within an environment. Individuals DO NOT evolve, rather populations evolve.
Evidence – For Descent w/ Modification	1. Direct Observation 2. Homology 3. Fossil Record 4. Biogeography
How old is the Earth?	Earth 4.6 Billion Years Old
Evidence – Biogeography	Earth 4.6 Billion Years Old Pangaea 250 mya Broke up 20 mya Comparison of organisms similarities and differences Endemic – Found there and only there
Endemic	Found there and only there
Pangaea	was a supercontinent that existed during the late Paleozoic and early Mesozoic eras formed 250 - 300 mya. Began breaking apart after about 100 million years
Analogous traits arise	when groups independently adapt to similar environments in similar ways
Convergent evolution does NOT	provide information about ancestry
Darwin's Theory	Species/populations change over time, they adapt, evolve over time by natural selection.
A theory of Science is based on.....	a broad collection of data and supporting evidence.
Genes	The basic unit of heredity, DNA code
Genotype	The Genes ex.
Phenotype	The physical characteristics, EX: Red Hair
Does Genotype always lead to Phenotype?	NO - some phenotypes are not heritable
Species	Group of actually or potentially interbreeding natural population (individuals) which can and will interbreed to produce fertile offspring
Population	A group of individuals of the same species that live in the same are and interbred
Evolution works on.....	Populations
Natural Selection works on ...	Individuals
Microevolution works on ....	Changes in allele frequencies in a population
Three main causes that drive genetic changes	1. Natural Selection 2. Genetic Drift 3. Gene Flow
Sources of Genetic Variation	Mutation Position and Number altered Reproduce Quickly Sexual reproduction
Point Mutation	Alter one base in a gene
Source of most genetic variation	Sexual Reproduction
Hardy Weinberg equilibrium	p2 + 2pq+ q2 = 1
What does the Hardy Weinberg Equilibrium formula state?	If you give me the frequency of genes in a population, I will tell you the frequency of individuals in a population
Calculate p allele	p = White x 2 + Pink x 1 Total Population X 2 White is X 2 because each white individual has two p alleles Pink is X 1 because its genotype pq has one p allele. The total population has to be doubled to account for each individual having 2 alleles
4 Key Points of Genetic Drift	1. Genetic drift is significant in small populations 2. Change may be random 3. It can lead to a loss of genetic variation 4. Can cause harmful alleles to be fixed
Relative Fitness	Contribution to the gene pool of the next generation RELATIVE to the contributions of others EX: "survival of the fittest", some males lock horns
3 Modes of Selection	Directional, Disruptive and Stabilizing
Directional Selection	Favors individuals at one end of the phenotypic
Disruptive Selection	Favors individuals at both extremes of the phenotypic range
Stabilizing selection	Favors intermediate variants and acts against extreme phenotypes
Sexual selection	natural selection for mating success
What can sexual selection result in?	sexual dimorphism
Male showiness	due to mate choice can increase a male's chances of attracting a female, while decreasing his chances for survival
The good genes hypothesis suggests...	that if a trait is related to male health, both the male trait and female preference for that trait should be favorably selected
What do you need in order to distinguish species?	1. Morphology 2. Physiology 3. Biochemistry 4. DNA
Reproduction Isolation	Biological barriers that impede members of two different species from producing viable, fertile offspring
Reproduction Isolation Purpose	Limit hybrids; offspring from interspecific mating
Prezygotic barriers	block fertilization
Postzygotic barriers	preserve isolation after fertilization
Morphological species	characterized by body shape EX: Pheidole barbata
Ecological species	characterized by its ecological niche EX: Galapagos finches
Phylogenic species	smallest group sharing common ancestor
What has a high degree of allopatric speciation?	Island Biology
Two forms of Polyploidy	Autopolyploid Allopolypoid
Patterns with Hybrid Zones	A hybrid zone can occur in a single band where adjacent species meet Hybrids often have reduced fitness compares with parent species *The distribution of hybrid zones can be more complex if parent species are found in multiple habitats within the same region
Rate of Speciation	Punctuated Equilibrium Gradualism *Once speciation occurs, divergence can happen quite quickly
Two things that Rate of Speciation tells us...	1. It may be millions of years to create a new species. 2. Once gene flow has been interrupted, there must be continued divergence to become reproductively isolated
How Old is the Earth?	4.6 Billion Years
Origin of Earth	Earth's early atmosphere likely contained water vapor and chemicals released by volcanic eruptions (nitrogen, nitrogen oxides, carbon dioxides, methane, ammonia, hydrogen, hydrogen sulfide)
Earliest evidence of life on Earth?	3.5 Billion Years ago
Ribozymes	An RNA that functions as an enzyme too. AKA Catalytic RNA
Sedimentary Rocks	are deposited into layers called Strata and are the richest source of fossils
The fossil record reveals....	changes in the history of life on Earth
Fossil Types	Molds/Prints Trace Amber
Sedementary Strata	Reveal the relative age of fossils
Radiometric Dating	How the absolute age of fossils can be determined
Half-life of an isotope	time require for half the parent isotope to decay
What happens to a "parent" isotope?	it decays to a "daughter" isotope at a constant rate
Age of prokaryotes	3.5 Billion Years
Age of oxygen	2.7 Billion Years
Age of Eukaryotes	2.1 Billion Years
Age of Cambrian Explosion	542 Million Years
Age of Colonization of Land	500 Million Years
Age of Jurassic	200 Million Years
First single celled organisms	Stromatolites, Mats (3.5 Million Years, or earlier) "Transformed life on the planet"
Multicellularity (1.5bya)	The first multicellular organisms were most likely algae Ice ages suppress the process 565mya Earth thaws and diversity increases
Evidence for Endosymbiont Model	1. Replicated - Direct observation (5yrs) (the following are similarities between endosymbionts and prokaryotes) 2. Enzymes and transport systems 3. Replication 4. DNA 5. Size 6. Antibiotics / Ribosomes
First Eukaryotes (2.1bya)	Endosymbiont model Mitochondria & Plastids See pg 517 Mitochondria first
Oxygenic Pathway (2.7bya)	02 dissolves in water 02 reacts with Fe to create Iron Oxide 02 then saturates water 02 gasses out and reacts with Fe on land 02 then saturates the atmosphere Mass extinction of the prokaryotes… why?
Cambrian Explosion	Major changes Soft bodies herbivores become armored predators Sponges Cnidarians Molluscs
Land Colonization (500mya)	Organisms moving onto the land had to adapt to arid conditions Plant adaptations Animal adaptations
Affecting Life on Earth	Three major processes affecting life on this planet 1. Continental drift • 2. Mass Extinctions • 3. Adaptive Radiations •
Continental Drift	Process of plates moving (plate tectonics not discovered until 1915* thanks Spring 2012 students) Rate Pangaea
If all the continents come together what two significant things would happen?	1. Habitat alteration – Canada used to be equatorial. Sea rise and fall. Where will the polar bears go? 2. Allopatric speciation – geographic isolation causing speciation.
Evolutionary Trends	Extracting a single evolutionary progression from the fossil record can be misleading
Evolutionary Novelties	The eye The ear
Systemics	discipline focused on classification and determining evolutionary relationships
Phylogeny	Evolutionary history of a species
Correct way to write Scientific names	Cardiospermum halicacabum Image: 44608128-bee2-438d-bf75-940e1a8894ce (image/jpg)
Taxonomic Hierarchy	Image: 9b6a9b03-e0c2-43bd-828f-35bbb5e89e8a (image/jpg)
Example of a rooted tree	Image: 1dde6331-a3b3-4922-97e7-528897c6b381 (image/jpg)
Cladogram	Image: 0033f7eb-30cf-4c7c-8c09-35c16672007c.PNG (image/PNG)
Shared primitive character	A characteristic that share beyond the clade under study
Ingroup	group of related species under study
Outgroup	a species or group of species that are closely related to, but are outside he ingroup
Phylograms	length of branches reflect the number of changes that have occurred to a particular DNA sequence in that lineage
Ultrametric trees	the pattern is the same as a phylogram, but all branches traced to a common ancestor are the same length. Illustrates survival period for the lineage rather than the number of DNA changes
How does an Ultrametric tree differ from a phylogram?	on an Ultrametric tree the branches traced to a common ancestor are the same lenth
Hypothesis for the origin of life on Earth	a. Abiotic synthesis of organic monomers. b. Abiotic synthesis of polymers. c. Formation of protobionts. d. Origin of genetic information.
Is evolution goal oriented?	NO Evolution simply depends on the environment which the organisms live and try to survive.
The Endosymbiotic Theory	The theory of Endosymbiosis explains the origin of chloroplasts and mitochondria and their double membranes. This concept postulates that chloroplasts and mitochondria are the result of years of evolution initiated by the endocytosis of bacteria and blue-green algae. According to this theory, blue green algae and bacteria were not digested; they became symbiotic instead.
Environmental challenges of living on land	Obtaining enough water Preventing excessive water loss Getting enough energy The photosynthesis/water trade-off
What type of mutation plays the most important role in increasing the number of genes in the gene pool?	Duplication (Gene duplication is an important source of new genetic material)
Which of the following is the best example of gene flow?	Wind blows pollen from one population of plants to another and cross-fertilization occur (Over several generations the two populations will become more similar)
Which of the following reproductive barriers actually prevents individuals of closely related species from copulating successfully?	Mechanical Isolation (With mechanical isolation, mating cannot occur successfully due to incompatibility of reproductive parts)
Mutations in what class of genes have probably been responsible for many of the changes leading to the great diversity of life existing today?	Developmental genes (Small changes in developmental genes such as Hox genes can produce large morphologic changes)
There are two groups of pine trees that appear to be very similar phenotypically and genotypically. However, one releases pollen in January, when the female structures of that group are receptive, and one in March. What kind of reproductive barrier is this?	temporal isolation (Temporal isolation occurs when two similar species have sexual rediness at different times)
How did some strains of Staphylococcus aureus become resistant to antibiotic drugs?	Some members of the bacteria population must have had a genetic variation that made them resistant to antibiotics, and these bacteria had greater reproductive success than sensitive individuals. (Those bacteria that survived the various antibiotic drugs passed on to subsequent generations the genes that enabled them to resist the drug)
Lyell's principle of unifomitarianism _______?	strongly influenced Darwin's view of how living organisms could change over time. (Darwin eventually embraced the idea of an old Earth rejected the idea that living organisms had been specially created. He applied the idea of slow change to the evolution of oranisms.)
In Hardy-Weinberg equation, p2 represents ____________?	the expected frequency of homozygous dominant individuals in the population (the frequency of the dominant allele (A); thus p2 represnts the frequency of homozygous dominant individuals (AA:p*p=p2)
Selection that acts over evolutionary time to preserve traits that increase an individuals ability to mate is known as _______?	sexual selection (In sexual selection, secondary characteristics that may not seem to be adaptive in the general sense may give an individual an advantage in gaining a mate and producing fertile, viable offspring)
In the Hardy-Weinberg equilibrium, 1 represents ______________?	the sum of the frequencies of the genotypes for a particular gene locus (The sum of the frequencies of the genotypes must equal 1 in any population)
What is the name of the theory that suggests that eukaryotic organisms evolved from engulfing prokaryotic organisms and then creating an obligate relationship with them?	Endosymbiont
What is the term given to an organism that becomes able to reproduce (accelerated reproductive development) before the body is an adult (somatic development).	Paedomorphosis
Scientific names (Genus species) are better to use than common names because they clear up ambiguities, particularly misunderstandings based on language barriers	True
Show the events of life on Earth in the correct order.	* Origin of Earth - 4.6 Billion Years Prokaryotes- 3.5 Billion Years Oxygen - 2.7 Billion Years Eukaryotes - 2.1 Billion Years Cambrian Explosion - 542 Million Years *Colonization of Land - 500 Million Years Jurrasic - 200 Million Years
cephalic index or cranial index	is the ratio of the maximum width of the head of an organism (human or animal) multiplied by 100 divided by its maximum length (i.e., in the horizontal plane, or front to back). The index is also used to categorize animals, especially dogs and cats.
long-headed	Females - less than 75 Males - less than 75.9 Scientific name: DOLICHOCEPHALIC
Short headed	Females- 75-83 Males- 76-81 Scientific Name: MESATICEPHALIC
short-headed	Females- greater than 83 Males- greater than 81.1 Scientific name: BRACHYCEPHALIC
What prevents closely related species from reproducing?	Behavioral isolation is an important evolutionary mechanism that helps members of the same species identify each other as proper mates.
Intrasexual selection	selection within the same sex example, some male animals compete against one another, physically, for access to females
Intersexual selection	selection between the two sexes the bright plumage of a male peacock does not help it physically overcome rival males.But female peacocks tend to prefer male peacocks with bright plumage:
Evolution is a process resulting in changes in the ________ of populations over time	genetic makeup
correct order from the most broad classification to most specific.	Dumb Kings Play Chess On Fine Glass Sets Image: 43a07250-7007-4806-9d59-fd54e6968909 (image/png)
Which of the following i a key observation that must be explained in a unifying theory of life?	Many basic characteristic are shared by all living things (Organisms do share many basic characteristics. Darwin reasoned that the diverse organisms found on Earth today evolved from a few common ancestors)
The breeding of plants and animals for particular traits by humans is called....	artificial selection
What did Darwin observe about species on islands?	They are often closely related to species from the nearest mainland or neighboring islands. (If a species that dispenses from a mainland to an island succeeds in its new environment, it may give rise to several new species as populations spread to other islands in the archipelago.)
Vestigial organs are ............	remnants of structures that were useful to an organism's ancestors, but which are no non-functional or show reduced function (For example: some species of snakes have remnants of pelvic and leg bones)
During his voyage around the world, Darwin was inspired to think about evolution by............	fossils he collected studying adaptations of organisms to their environments * the works of others such as Lamarck *the unique organisms he saw in the Galapagos Islands
At the time Charles Darwin sailed on HMS Beagle............	several biologists had proposed that species might change over time, but none had suggested a convincing mechanism that might cause the change
Two lines of evidence to support Darwin's theory of descent with modification in natural populations	Organisms within a population vary, and all populations produce more offspring then can be supported by the environment, resulting in competition for survival within the population
On an evolutionary tree.......	homologous characteristics form a nested pattern
In Darwin's view of descent with modification.......	natural selection can improve the match between an organism and its environment (Natural selection acting in a particular environment can increase the compatibility between an organism and its environment)
A population of zooplankton is exposed to a small number of predatory fish that feed on the larger-sized (adult) zooplankton. What prediction would most likely occur based on the principles of natural selection?	The population will come to contain adult zooplankton that reach sexual maturity when they are still relatively small. (This would permit the zooplankton to reproduce in spite of the predation pressure on larger individuals)
What insight did Darwin gain from reading Thomas Malthus's essay on human suffering?	Organisms have the capacity to produce more offspring than the environment can support (Matheus contended that human suffering is a product of humans reproducing faster than food and other resources can increase. This is actually a characteristic of many life-forms on Earth.)
The scala naturae, or scale of nature, is based on the ideas of..........	Aristotle (Aristotle believed that all life forms could be arranged o a ladder, or scale, of increasing complexity)
Animals that possess homologous structures probably..............	evolved from the same ancestor (Homology refers to similarity attributable to common ancestry)
All know organisms translate genetic information to produce protein molecules via the same genetic code. This finding strongly supports the hypothesis that..........	all organisms are decended from a single common ancestor (A common genetic code is overwhelming evidence that all life is related)
Evidence from molecular biology supports the theory of evolution by demonstrating that...............	closely related organisms have more similar DNA and proteins than more distantly related organisms (Evolutionary relationships among species are reflected in their DNA and proteins. If two species have similar libraries of genes and proteins, with sequences of monomers that match closely, the sequences most likely descended from a common ancestor)
Lyell's principle of uniformitarianism..........	strongly influenced Darwin's view of how living organisms could change over time (Darwin eventually embraced the idea of an old Earth and rejected the idea that living organisms had been specially created. He applied the idea of slow change to the evolution of organisms.)
Herbivory	An example of the process of evolution (Herbivory is involved in the process of natural selection, since populations of herbivores must become adapted to particular plant species on which they feed)
Carolus Linnaeus is considered to be the founder of .......... and he..........	the binomial classification system........thought that resemblances among different species reflected the pattern of their creation (Although he is considered the founder of taxonomy, Linnaeus accepted the theory of creation)
Abiotically produced vesicles display which of the following rudimentary qualities necessary for life?	the ability to perform simple reproduction and metabolism (Abiotically produced vesicles are capable of dividing and performing simple metabolic reactions)
According to the theory of evolution anatomical and molecular homologies should ______________?	produce very similar patterns of evolutionary relatedness (According to evolutionary theory, anatomical and molecular homologies should generally produce evolutionary patterns that corroborate each other)
Researchers can use molecular homologies to ________________?	reveal the number of mutations in a particular sequence that has occurred in each species since they diverged from a common ancestor (Over long periods of time, insertions and deletions accumulate)
What is the correct order of the geologic eras, from most ancient to most recent?	Paleozoic Mesozoic Cenozoic (The Paleozoic was followed by the Mesozoic. The current era is the Cenozoic)
The modern idea of extinction as a common occurrence in Earth's history was first proposed in the early 19th century writings of ________________?	Cuvier (Cuvier advocated catastrophism, speculation that extinctions apparent in the fossil record corresponded to a catastrophe, such as a flood or drought)
Birds and mammals have a four-chambered heart, but most reptiles have a three-chambered heart. How does this fact affect the construction of phylogenic trees for these groups?	The most likely tree is not always the most parsimonious (Evidence shows that the ancestors of mammals diverged from reptiles before the ancestors of birds did; therefore, there is no common ancestor of birds and mammals that had a four-chambered heart. This character must have evolved twice)

Next up

Description

Resource summary

Similar

	Created by Sisa Fable almost 10 years ago