Cumulative Info (w/ Unit 4) Flashcards
(122 cards)
what is special creation?
species don’t change and are separately created
lineages don’t split
earth is young
what is descent with modification?
species change overtime
lineages split and diverge
new life comes from older forms
earth is old
what is microevolution?
changes in species
what are vestigial traits?
important in ancestors but now serves no purpose
what is the biological species concept?
if individuals interbreed and don’t produce offspring, they are SEPARATE species
when did Darwin publish “on the origin of species”?
1859
what are the four stages of evolution?
- variation among individuals
- division into distinct groups
- distinct population with little inbreeding
- irreversible reproductive isolation
what is macroevolution?
major changes that create new form from an older form
what are transitional forms?
in between organism of a species being evolved
EX: dinosaur —archaeopteryx–> modern bird
what developed first, feathers or flight?
feathers
what is homology?
the study of likeness
-human arm, mole paw, horse leg, dolphin fin, bat wing
what are nested sets?
they are used to determine what species share and use common traits b/w them
what is natural selection?
traits that promote survival and reproduction are passed to the next generation
-not always those most fit survive
-NOT goal-oriented
does natural selection work on phenotypes or genotypes? is natural selection perfect?
phenotypes
-they produce imperfect adaptations that are reflexed in a population
what is the process of natural selection?
- variation exists
- variation is heritable
- not all reproduce
- some reproduce more
what are the natural selection tenets? (modern synthesis - combining molecular science and natural selection)
- individuals exhibit variation due to mutations
- the variation is passed down to offspring
- some are more successful at surviving and reproducing
- the most successful have variation that are best adapted to their environment
what is adaptation?
traits that increase fitness relative to those that lack
what are exaptations?
adaptive traits that initially had a different function but now are used in a new way
-panda’s wrist bone shifted into acting as ‘thumb’
what is artificial selection?
-works similar to natural selection except it produces varieties less likely favored in nature
-EX: GMO’s of tomatoes
what is a phylogenetic tree? (1837)
hypothesis of the history of divergence and evolutionary change
-single species and its several descendants
-based on DNA
REFER TO DRAWING IN NOTEBOOK FOR TREE TERMS
what is a polytomy?
simultaneous divergence of taxa
-3-way split due to uncertainty and insufficient data
what are synapomorphies?
derived characteristics shared by 2+ species
what is an apomorphy?
a new derived character that appears in a tree, “separate from”
-NOT GOOD
what is a plesiomorphy?
pre-exisiting ancestral character, “near from”
-a trait in an ancestor that disappeared, but came back again later in the tree
-NOT GOOD