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Tracking Human Evolution: Where Do We Fit on the Tree of Life? Geology 230 Fossils and Evolution Phylogenetic Classification of Humans

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Tracking Human Evolution: Where Do We Fit on the Tree of Life? Geology 230 Fossils and Evolution Phylogenetic Classification of Humans Tracking Human Evolution: Where Do We Fit on the Tree of Life? Geology 230 Fossils and Evolution Phylogenetic Classification of Humans Life on Earth Eukaryota Animalia Bilateria Deuterostomia Chordata Craniata Vertebrata Gnathostomata Osteichthyes Sarcopterygii Tetrapoda Phylogenetic Classification of Humans Reptiliomorpha Amniota Synapsida Therapsida Mammalia Eutheria Primates Anthropoidea Hominidae Homo H. sapiens Tree of Life Web Project http://tolweb.org/tree/phylogeny.html Root of the Tree, Life on Earth: http://tolweb.org/Life_on_Earth/1 Eukaryotes http://tolweb.org/Eukaryotes/3 Animals, Metazoa http://tolweb.org/Animals/2374 Bilateria http://tolweb.org/Bilateria/2459 Deuterostomia http://tolweb.org/Deuterostomia/2466 Chordata: dorsal nerve cord http://tolweb.org/Chordata/2499 Exemplar fossil: Yunnanozoon or Haikouella, Cambrian Yunnanozoon (Haikouella), a cephalochordate from the Lower Cambrian of China Urochordates: Sea Squirts. Adults have a pharynx with gill slits. Larval forms are free-swimming and have a notochord. Chordates are thought to have evolved from the larval form by precocious sexual maturation. Tunicates or Sea Squirts mobile larva sessile adult Cephalochordate: Branchiostoma, the lancelet Craniata: skull http://tolweb.org/Craniata/14826 Vertebrata: vertebrae http://tolweb.org/Vertebrata/14829 A living jawless fish, the lamprey Gnathostomata: jawed vertebrates http://tolweb.org/Gnathostomata/14843 The placoderms were the armored fish of the Paleozoic. Grew up to 10 m in length. Placoderm, Dunkleosteus, Devonian of Ohio Placoderm, Devonian of Australia Osteichthyes: Bone structure in fins of ray-finned and lobe-finned fish Fish Anatomy: Lobe-finned fish Sarcopterygii: lobe-fins http://tolweb.org/Sarcopterygii/14922 Sarcopterygian, lobe-finned fish, Devonian of Scotland An Australian lungfish with well developed lobe fins Coelocanth, a living lobe- finned fish Skeleton of the coelocanth A Coelocanth Evolution of the tetrapod walking leg from the lobe fin Sauripterus, rhipidistian, Late Devonian, Pennsylvania Evolution of tetrapod legs from lobe fins, late Devonian to early Mississippian Evolution of Tetrapods Prothero, 2007 Late Devonian fin with fingers from a lobe- finned fish, Pennsylvania Tiktaalik rosea from the Late Devonian of Ellsmere Island, Canada, 2006 Tiktaalik rosea from the Late Devonian of Ellsmere Island, Canada, 2006 Tiktaalik rosea on Colbert Report Lobe-Fins to Tetrapoda: four legs http://tolweb.org/Terrestrial_Vertebrates/14952 Tetrapods: Acanthostega and Ichthyostega, Devonian of Greenland. Lobe-Fin Fish or Tetrapods? Skull roof of the Late Devonian Ichthyostega Acanthostega using its legs to lift its head out of the stagnant water to breathe Hindlimb of Ichthyostega, Devonian of Greenland Fish with Fingers, Jenny Clack Ichthyostega: Photographs of part and counterpart superimposed to show seven digits Changing Digits from the Late Devonian to Early Mississippian Reptiliomorpha http://tolweb.org/Terrestrial_Vertebrates/14952 Amniota http://tolweb.org/Amniota/14990 Crocodiles hatching from their amniote eggs.
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