evolution & classification Flashcards
early earth conditions
lack of O2, less oxidation, high concentration of methane, CO2, temperatures, ultraviolet light penetration
membrane formation hypothesis:
phospholipid bilayers make small membrane enclosed areas with diff internal chem compared to environment
LUCA
3 domains of life: archae, bacteria, and eukaryotes
representative of an ancient community of organisms
CO2 occurs in 3 varieties:
^12 C, ^13 C, ^14 C
which carbon varieties are used in photosynthesis?
^12 C
biomarkers
molecular fossils of organisms and other compounds
stromatolites
structures created by cyanobacteria living in shallow water
molecular clock
accumulation of nitrogen base/aa sequence to estimate when clades diverged from a common ancestor
divergent evolution
(homologous)
development of different adaptations in species similar to each other
convergent evolution
(analogous)
develop of similar adaptation due to similar selection pressures
vestigial structures
structures that have lots much or all of their original function through evolution
Stromatolites
structures of microbes/bacteria that are billions of years old that do photosynthesis
paradigm shift
fundamental change in underlying assumptions
clutch size is under what type of selection?
stabilizing
stabilizing selection
average individuals are favored
directional selection
one trait is favored
disruptive selection
2 traits are favored
average individuals are rejected
homologous structures
same structure diff function
analogous structures
diff structure diff function
transitional links
fossils appearing to be intermediates between species
adaptive radiation
rapid diversification of single ancestral line
allopatric speciation
when speciation occurs due to geographic isolation
polyploidy
multiple sets of chromosomes
