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Terms: Homology vs homoplasy: - Homology: similarity between taxa resulting from a common ancestor, stems from divergent evolution. Examples: vertebrate limbs, which emerged from a common ancestor but have different functions. Homoplasy: similar characteristics in different organisms that arose separately (Seeley). Stems from convergent evolution. E.g. wings of birds/bats/insects Synapomorphy vs Autopomorphy vs Plesiomorphy vs Apomorphy: - Synapomorphy: shared, derived character. - Autopomorphy: a derived (new) character that´s present in only one taxon on your tree - Plesiomorphy: a primitive, ancestral trait - Apomorphy: a novel evolutionary trait unique to a particular species and all its descendants, e.g. feathers to birds; defines all members of Aves Theory vs law vs hypothesis: - Theory: a group of propositions formulated to explain a group of facts, repeatedly confirmed through experiments - Hypothesis: a premise/assertion subject to testing/falsification; only after many failures to falsify a hypothesis does it become a theory - Law: observed phenomenon which always applies under the same conditions, but doesn´t necessarily explain why the phenomenon occurs Darwinian vs Larmackian evolution: Monophyly vs Paraphyly vs Polyphyly: - Monophyly: a group that includes an ancestor and all its descendants - Paraphyly: a group that consists of an ancestor and only some (but not all) of its descendants - Polyphyly: a group that doesn´t share a recent common ancestor; grouped on similarities unrelated to ancestry, like a streamlined body Cladistics vs Phylogenetic Systematics vs Linnaean Systematics: - Cladistics: shows relations among organisms - Phylogenetic systematics: the field within biology that reconstructs evolutionary history - Linnaean systematics: organisms grouped according to shared characteristics, not evolution; fixed categories, with kingdom at the top and subspecies at the bottom Extinction vs Mass extinction: Ontogeny: origination and development of an organism; feathers form in ontogeny. Recapitulation: repetition of ancestral changes in an organism´s ontogeny; means that in the development of an animal throughout its ontogeny, it goes through stages resembling the stages in the evolution of its ancestors.

Atavism: when an ancestral trait appears, after having been lost through evolutionary changes (e.g. tails in humans) Age of fishes (Paleozoic) vs Age of reptiles (Mesozoic) vs Age of mammals (Cenozoic = tertiary + quarternary)...