Homologous vs Analogous Organs — Comparison Note — Notes | NoteTube

Feature	Homologous Organs	Analogous Organs
Embryonic origin	Same (identical developmental pathway)	Different (independent developmental pathways)
Adult function	Different	Similar (same function)
Structural plan	Similar $\frac{same bones}{tissues}$	Different (different architecture)
Evolution type	Divergent evolution	Convergent evolution
Common ancestry	Proven (YES)	Not proven (NO)
Environmental implication	Different environments, same ancestor	Similar environments, different ancestors
Animal examples	Forelimbs: whale, bat, horse, human	Wings: bat vs butterfly; eyes: octopus vs mammal
Plant examples	Thorns (Bougainvillea) and tendrils (Cucurbita) — both stem	Tendrils of Cucurbita (stem) vs Pisum (leaf)
NEET signal phrase	"Same origin, different function"	"Different origin, same function"
Evolutionary conclusion	Species diverged from a common ancestor	Species independently evolved similar solutions

Are they both mammals? → Almost certainly homologous forelimbs
Is one a vertebrate and one an invertebrate performing the same function? → Almost certainly analogous
Are they modifications of the same plant organ (stem/leaf/root) but with different functions? → Homologous

Bat wing vs. bird wing = HOMOLOGOUS (both vertebrate forelimb modifications)
Bat wing vs. butterfly wing = ANALOGOUS (mammalian forelimb vs. chitinous exoskeletal extension)
Dolphin flipper vs. shark fin = ANALOGOUS (mammalian forelimb vs. fish fin, different origins)
Human arm vs. whale flipper = HOMOLOGOUS (both mammalian forelimbs)