BIOL 121 Lecture Notes - Lecture 17: Galapagos Penguin, Paddle Steamer, Hms Beagle
Document Summary
Charles darwin: key events during 5-year voyage of the h. m. s. Beagle: dar(cid:449)i(cid:374)"s o(cid:271)ser(cid:448)atio(cid:374)s (cid:894) outh america & galap gos is. ) Stunned by diversity of species compared to those in europe. Different species compared to those in europe. Wonderful adaptation of species to different environments: e. g. marine iguana vs land iguana, e. g. birds blue-footed booby; greater frigate birds, e. g. flightless birds: Gal pagos island penguins (spheniscus mendiculus: vestigial wings have become flippers (useless for flight in air) Steamer ducks -south america (trachyeres brachydactyla: flap their wings into the water (as well as using their feet) creating an effect like a paddle steamer. Fossil collections: enormous number of species now extinct. Fossils changed over time (in different soil layers), more recent fossils more like present-day forms than the older fossils (cid:862)two of a kind(cid:863) Years later, darwin would eventually ask himself: Dar(cid:449)i(cid:374)"s o(cid:271)ser(cid:448)atio(cid:374)s - (cid:862) pe(cid:272)ies varied slightly fro(cid:373) pla(cid:272)e to pla(cid:272)e(cid:863: e. g. giant tortoises (geochelone nigra)
