traits that are similar in diffirenet species because the species share a common ancestor.
- example: human, whale, bat, bird
inherited, but reduced in size & often unused.
example: snake's hip.
- characteristics that are similar in function but different in structure.
- example: butterfly wing vs. bird wing
change over time
which evolve, and which do not?
- species evolve.
- individuals do not.
differences between member of a species
Variation is: (4)
- physical (height)
- chemical (blood type)
Variations are genetically determined by (2)
- Mutation: change in genetic sequence
- Recombinant: combination of 2 DNAs
What are Darwin's 4 theories of natural selection?
- 1.) there is variation within a population
- 2.) some variations are helpful
- 3.) not all of the offsprings survive
- 4) those who survive are the ones with beneficial traits. in that enviornment
What are the 4 Evidences of Evolution?
- Fossils and fossil record
- Anatomical structures
- Embryological structures
- Biochemical structures
what are fossils
it can include what? (2)
- the preserved remains or traces of animals, plants and other organisms of the past.
- Imprints and Remains.
What is the fossil record?
one of the early sources of data relevant to the study of evolution
What can fossils do to thelp scientist learn about evolution?
- it can be dated. provides scientists with a timeline.
- it shows history of life on earth.
How does Biochemical evidence help?
it is evidence that macromolecules are the same, we use the same energy souce and we both have the same genetic material.
What are the four macromolecules?
carbohydrates, protein, lipids and nucleic acids.
what energy do all living things use?
What is the genetic material all living things use.
What are the 3 Anatomical Structures?
Define them once again or mark this wrong.
Vestigial Structures, Homologous Structures and analogous structure.
What do all 3 provide?
evidence to evolution.
what do homologous and vestigial have in common?
provides evidence of our relationship with out common ancestry.
what is embryology?
study of the early stages of development of an embry.
What is Artificial Selection?
It's like natural selection, but humans interfering.
what is speciation?
the evolution of one or more species from a common ancestor.
formed by what? (2)
interbreeding population of organisms that produce healthy, fertile offsprings.
isolation & natural selection
new species will develop when members become separated from other member of the same species.
what would be the steps of isolation going into natural selection?
- isolation would occur.
- then those species adapt to their new enviornemt.
- then the new enviornment acts upon the variation that exists....
- which leads to adaptation.
where did darwin travel to and what was his ship's name?
the galapagod islands on his ship called "The Beagle"
process in which one species gives rise to multiple species that exploit different niches.
what are the two types of isolation?
geographic isolation and reproductive isolation.
the physical separation of a population.
ex: seperated by barriers: mountains, rivers, oceans, lakes
the inability of formerly interbreeding organisms to produce healthy, fertile offsprings.
ex: since they cannot reproduce anymore : different species.
what are the three types of evolution?
divergent, covergent, co evolution
when isolated species evolve independently.
- due to geographic isolation (migration)
- ex: polar bears vs grizzly.
- are related, but different species.
what structure does it result in?
- different species evolve with similar characteristics.
- due to living in similar enviornment.
ex: butterfly & birds.
results in analogous structures. NOT RELATED.
a change in the genetic composition of one species (group) in response to a genetic change in another.
when species evolve TOGETHER because they depend on each other.
ex: birds & flowers.