Exam 1 Flashcards
Evolution
change over time
Theory
a comprehensive explanation of some aspect of nature that is supported by a vast body of evidence and that generates testable and falsifiable predictions and hypotheses
Fact
some form of evidence that has been tested and confirmed so many times that there is no compelling reason to keep confirming it
Is evolution a fact or a theory?
both
Hypothesis
a proposed explanation for an observation or phenomenon that can be tested
Working hypothesis
a provisionally accepted hypothesis proposed for further testing, consideration, and research
Alternative hypothesis approach
a hypothesis created that debates the original hypothesis
-it is essential to avoid trap of the incorrect “pet hypothesis”
Pet hypothesis
the hypothesis you want to believe versus the once based on observations and predictions
Darwin’s Theories of Evolution
-evolution as such
-gradualism
-descent with modification
-multiplication of species
-natural selection
-sexual selection
Non-Darwinian Theories of Evolution
-genetic recombination (flu)
-genetic drift
Mechanisms of Evolution
-natural selection
-sexual selection
Patterns of Evolution
-evolution as such
-gradualism
-descent with modification
-multiplication of species
Evidence for Evolution
-paleontological record
-vestigial organs
-extinction
-transitional forms
-evidence of descent with modification
-homologous structures
-molecular homology and fossil genes
-age of earth and geological time
Law of Succession
fossil types are succeeded, in the same geographic area, by similar fossils or living species (ex: south american armadillos)
Fossil genes (pseudogenes)
a gene that once produced a protein, but because of accumulation of mutations no longer does (not a switch gene that turns other genes on and off)
Examples of Vestigial Organs
-appendix
-tails in humans
-vestigial legs in snakes
-wisdom teeth in humans
-vestigial wings in New Zealand Kiwi
-vestigial hip and leg bones in whales
Examples of Extinction
-mammoths and mastadons
-titanotheres (large herbivore)
-glyptodont (large armadillo like)
Examples of Transitional forms
-bats with claws
-snails to slugs (snails have a shell, slugs do not)
Evidence of Descent with Modification
-phylogenic trees
-titanothere
Homology
similar characteristics among species
-structural homology
-developmental homology
Structural Homology
-all mammals have the same or very similar bone structure in the arm/wing/flipper
-indicates descent with modification from a common ancestor
Carolus Linnaeus
father of modern taxonomy
Taxonomy
the science of describing, naming, and classifying species of living or fossil organisms (family, class, group, etc.)
Nicolaus Steno
discovered strata layers in rock (stratigraphy)
-discovered fossils