Evolution Unit

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Evolution Unit by Mind Map: Evolution Unit

1. Factors of Evolution:

1.1. Oscar Gives Carl Diamond Rings

1.1.1. 1. overproduction produces more offspring than environment can support based on malthus

1.1.2. 2. genetic variation each individual has different traits new traits appear by random mutations (a source of genetic diversity) we learned about sources of genetic diversity a while back in the reproduction unit

1.1.3. 3. competition organisms compete with one another for limited resources some traits have more of an advantage (adaptation)

1.1.4. 4. differential reproduction organisms w best adaptations live longer and produce more offspring more offspring --> their traits are more prevalent in the population

1.2. these factors lead to evolution

2. Scientists

2.1. Cute Little Llamas Make Dainty Wives

2.1.1. Cuvier Known as the Father of Paleontology; Studied the rock strata of the earth; Found that organisms were in different strata = established extinction as a fact.

2.1.2. Lyell did not believe in catastrophism; believed in uniformitarisnism catastrophism: major/sudden shanges shaped the earth uniformitarianism: slow changes (still occuring) shaped earth earth was millions (not thousands of years old) --> closer to actual 4.5 billion

2.1.3. Lamarck Thought that population changes over time Inheritance of acquired characteristics; Individuals could obtain traits over time and pass it to their children; Ex: I chop off my arm --> my daughter will not have an arm

2.1.4. Malthus Said the human population was limited by environment Individuals will compete for limited resources Cannot exceed the carrying capacity of their environment

2.1.5. Darwin Sailed on HMS The Beagle 1831-1836 Left from England --> South America --> Galapagos Islands --> Australia, South America, --> England Studied many living specimens and fossils along the way Did most important studies in Galapagos Used Finches and Tortises Darwin's Book: Origins of the Species by the Means of Natural Selection 1859

2.1.6. Wallace Came up with a similar theory on natural selection during Darwin's Time There was a race w Darwin to publish findings, but they were scared of the consequences of going against church ideas. Darwin published first (1859)

3. evidence of evolution

3.1. Freaky Bison Can Act Extremely Bossy

3.1.1. Fossils Definition: Remains or traces of an organism that died a long time ago Ex: dinosaur bones, fossilized footprints Show mass extinctions Most direct evidence of evolution Determining Fossil Age Relative Age Transitional species By studying the fossil record, we have species that have intermediate btwn hypothesized ancestors and descendant species

3.1.2. biogeography Definition: The Study of the location of organisms around the world Common ancestors migrated and evolved adaptations that best fit their new environments

3.1.3. comparative anatomy Definition: The study of structures found in living organisms to see how they are related to one another Types of Structures:

3.1.4. embryology Definition: Animal embryoes all start out looking the same Must have a common ancestor

3.1.5. biomolecules Definition: Scientist can compare DNA molecules and protein molecules from different species The more similar the nucleotide sequence and amino acid sequence, the more closely related the species are

3.1.6. examples of evolution darwin's finches european peppered moth tree color was white prior to industrial revolution --> moths were white tree color turned black bc soot and pollution --> moths turned black

4. selection

4.1. natural selection

4.1.1. survival of the fittest darwin refferred to organisms as being biologically fit fitness: organisms that are able to live longer and reproduce more are the most "biologically fit"

4.1.2. types of natural selection directional one extreme is favored over the average and opposite extreme happens when environmental changes are consistent and/or population migrates to a new environment stabilizing over time the average is favored over both extremes happens when environment is unchanging limits genetic diversity disruptive both extremes are favored and the average is selected against happens when one or more resource is limited

4.2. sexual selection v natural selection in guppies

4.2.1. natural selection predators select brightly colored guppies areas w high predators have dull guppies

4.2.2. sexual selection females select brighter mates areas w less predators have brighter guppies

4.3. artificial selection

4.3.1. when a human breeder chooses individuals (livestock, dogs, plants, etc) that will parent the next generation ex: dog breeds ex: tomato plants for best flavor not genetic engineering (genetic engineering alters genes, this is just selection of best genes)

5. Coevolution

5.1. when two or more species have evolved adaptations due to each other's influence

5.1.1. gazelles and cheetahs

6. methods of evolution

6.1. gradualism: organisms slowly change over time

6.2. puncuated equilibrium: long periods of no change followed by short periods of rapid change

6.3. both depend on hoe environment changes: rapidly or slowly

7. microevolution

7.1. when relative frequencies of alleles in a population change over a number of generations

7.1.1. evolution is occuring on a small scale

7.2. studies a gene pool

7.2.1. total collection of genes in a population at any one time

7.3. Hardy Weinberg Equilibrium

7.3.1. principle that the shuffling of genes that occurs during sexual reproduction alone is not enough to change the overall makeup of the population used to examine non evolving populations a population at HWE does not have evolution occurring

7.3.2. p + q = 1 for alleles!! p = frequency of dominant alleles q = frequency of recessive alleles

7.3.3. p^2 + 2pq + q^2 = 1 for genotypes!! p^2 = frequency of homozygous dominant 2pq = frequency of heterozygous q^2 = frequency of homozygous recessive

7.3.4. always start solving w q^2 the genotype can be gotten from the phenotype

7.3.5. criteria: population must be large population must be isolated (no immigration / emigration) mutations are not occurring mating is random (no sexual selection) equal reproductive success (no natural selection)

7.4. Causes of microevolution

7.4.1. Great Dramatic Beavers Forget Glasses For Sunny Sundays Genetic Drift How allele frequencies change due to chance Bottleneck Effect An event that causes a large portion of a population to die out/ be unable to reproduce Founder Effect When one portion of a population gets isolated from the main population Gene Flow Transfer of genes or alleles from one population to another Often caused by migration Sexual Selection (Non-random mating)

8. Speciation

8.1. Evolution leads to speciation

8.1.1. speciation: creation of new species

8.2. caused by:

8.2.1. geographical/habitat populations don't physically interact

8.2.2. temporal populations mate at different times (day, night, season)

8.2.3. behavioral populations are not attracted to mates of another (diff mating calls, dances, etc)

8.3. What is a Species?

8.3.1. Morphological concept: Definition: a species based on appearance and structure Easy to classify Some Species look very similar, some have great diversity

8.3.2. Biological concept: Definition: a species as a group of individuals that successfully reproduce with one another & have fertile offspring Objective (not affected by opinion) Asexual reproducers, extinct organisms, etc.