AP Bio Unit 7

Recognized variety in organism and inheritance

Great chain of being

Swedish naturalist and father of taxonomy

Developed a classification system that was for “tree like” than a ladder

British economist and demographer

“Struggle for existence”

Human population increases at a faster rate than out agriculture, therefore out food supply can run out

Darwin realized that same could be said for every species

The population that an environment can support

When resources are plentiful, population can grow fast.. less competition

Paleontologist

Helped prove extinction through his studies of fossils

Geologists

Theory of Uniformitarianism (Earth has always changed in uniform ways and that the present is the key to the past.)

Developed a theory of evolution

1. Use and disuse

   1. The more the body part was used, the larger it got

2. Acquired Characteristics'

   1. Characteristics acquired during an organisms lifetime can be passed to their offspring

British naturalist

Traveled and collected data on the HMS Beagle for almost 5 years

Noticed “Artifical selection” in dogs, asked if it could be applied to nature

Sent an essay that aligned with Darwins work, about the theory of natural selection

Descent with modification

1. Members of a population often vary in their inherited traits

2. All species can produce more offspring than the environment can support, this creating competition

Who is the ‘strongest’

the ones who produce the most sucessful offspring

Process in which individuals that have certain heritable traits survive and reproduce at a higher rate than do other individuals because of those traits

Only form under ideal conditions

Used to estimate age or organisms

Structures that are structurally similar but serve different purposes

Indicates common ancestry

Ex: Human hand and bat wing

Body part not used anymore but still remains in the organism

Ex: appendix

Serve the same purpose but built differently

Do not indicate common ancestry

ex: wings of birds and insects

Similar structure on the embryos of all vertebrates

Some disappear

Ex. tail, gill slits

Similarities in DNA sequences and amino acid sequences

Organisms evolve similar structures or similar adaptations to meet the same environmental challenges but do not share recent common ancestry

Instead they share analogous structures

Evolutionary history of a species or group of species

ex. the evolutionary history of birds

A thing, not something you do

The process of classifying things and figuring out their evolutionary history

Uses actual data, constantly changes based on new information

Naming things and classifying things based on a set of characteristics

Using a 2 part scientific name for every species

First part is the genus name

Second is the specific epithet

ex. Homo sapien

Domain

Kingdom

Phylum

Class

Order

Family

Genus

Species

Dumb King Phillip came over for great spaghetti

Any named group at any level

ex. Kingdom - Animalia

Branching diagram that:

Shows common ancestry

Displays differences

Matches taxonomy

New info may alter things

Term used in phylogenetic trees

Common Ancestor

Terms used in phylogenetic trees

Groups that share an immediate ancestor not shared by other groups

Terms used in phylogenetic trees

Lineage that diverages from all the other groups early on

Fossil records - youngest species are in the upper strata

Molecular homologies - compare amino acid and DNA sequences

Morphological homologies - homologous and vestigial structures

Way of determining phylogeny by looking at homologous structures

Based on: Common ancestry and shared characteristics

Includes a common ancestor and things descended from it

Like taxons, but a clade is monophyletic, not paraphyletic or polyphyletic

An ancestral species and all of its descendants

Matches

Ancestral species and some descendants

Doesn’t match

Has several species but not the ancestor

Doesn’t match

A character that extends beyond the taxon you are defining

Evolutionary novelty unique to a clade

The longer the branch, the longer the species has been around

Trying to measure the absolute time of evolutionary change

A change in the genetic makeup of a population from generation to generation

Mutations - most nucleotide changes do not have an effect on phenotype

Sexual reproduction

Chromosomal changes

The environment

Localized group of individuals that are capable of interbreeding and production fertile offspring

Groups of populations whose members have the potential to interbreed and produce fertile offspring but are unable to do so with other populations

The total of all alleles of all the genes in a population at a given time

Only one allele for a gene

No variation among members of a population with that gene

If the frequencies of alleles and genotypes doesn’t change from generation to generation, then it is in equilibrium and is not evolving

If it does change, then the population is evolving

Large population

No gene flow

No mutations

Random Mating

No natural selection

Change in gene pool due to luck or chance

When lots of members die and the surviving population is no longer representative of original population

When some individuals become isolated from the larger population

Leads to inbreeding

More likely in smaller populations

Can cause allelic frequency to change randomly

Loss of variation

The transfer of alleles into or out of a population

Usually reduces differences between populations

Some members of a population have more reproductive success than others

Because genes better match the environment

Contribution of a genotype to the next generation compared to another genotype

Sterile organisms - zero relative fitness

Favors one extreme for a phenotype

Usually occurs when environment changes or populations move

When conditions favor both extremes

Usually leads to new species

Acts against extremes and favors the average individual

When natural selection maintains stable frequencies for 2 or more phenotypic forms in a population

Changes above the species level

Formation of a new species

Characterizes species by body characteristics

Con: Analogous structures and convergent evolution

Focuses on fossil record

Con: They’re all dead

Focuses on a species niche

Niche - the role or job a species has in a community

Cons: Assumptions get made, difficult to define a species niche

Each species has a unique genetic history by comparing physical and molecular differences

Cons: Genetic differences are a difficult way to separate species

Members of the same species have to be able to interbreed and produce fertile offspring

Cons: extinct species

Produces new species

Many types that fall into one of two categories

Keeps two things from mating

Keeps offspring from mating

Two different species occupy different geographical areas

Species breed at different times

ex. day, year, dif plants bloom at dif times of the year

Courtship rituals are unique to a species

ex. bird mating calls

Morpholgical differences prevents mating

ex. plants with different pollinators

Sperm cannot fertilize egg

Genes of different parent species may interact and impair hybrid’s development

Hybrids are sterile

Meiosis fails becuase of different chromosome structure or number

Hybrids are fertile but when they reproduce their offspring are weak

When population is divided into geographically isolated populations

Speciation that occurs when populations overlap

Due to chromosomal changes and non-random mating

Two species interbreed and produce fertile offspring

Gradual changes lead to new species at regular intervals

Period of stasis interrupted by periods of rapid change

Majority of changes occur at the start

Abiotic synthesis of organic molecules

Amino acids and nucleotides

The building of polymers from monomers

Polymers have been produced by dropping monomers onto hot clay, sand, rock

Protocells - packaging polymers into membrane bound structures that maintain internal chemistry

Origin of self-replicating molecules, making inheritance possible

Electron adding

Water vapor, CO2, nitrogen, methane, ammonia

Oceans were a ‘primitive soup’ of organic molecules

Proved that energy could create monomers

Volcanic eruptions

From Space - meteorites

Thermal vents and submerged volcanoes

Started in ice - eutectic freezing made it possible

Aggregates of abiotically produced molecules surrounded by a membrane or

membrane-like structure

RNA molecules with catalytic capabilities

Self-splicing and replication

Transports molecules

Fossils buried deeper are older

Can compare strata across continents

Life begins

Prokaryotes dominated Earth

oxygen accumulates

Indicates photosynthesis

Eukaryotes

A cell that lives inside a host cell

Multicellularity - the first multicellular organisms began as colonies

The Cambrain Explosion

Huge diversification of animals

Colozination of land

Needed to prevent dehydration

Periods of change in which many new species form from one species

Small changes in DNA may lead to big changes