Chordate: dorsal notochord-supporting rod, most have during embryos. Dorsal hollow nervechord-branch at regular intervals and connect to organs and muscles and sense organs. Pharyngeal poucehs-paired in throat. Fishes and amphibians, slits devlop that connect to pharyngeal poucehse. Develope into gills. Only druing emboryonic devlopment, in humans become eustachian tubes, tonsils, thymus, and parthyroids. Tails-at some point. Chondrichtyes: sharks & rays. Actinopeterygii: ray finned fish/ Sarcopterygii: lobed finned & lung fish. Amphibia: frogs & salamanders. Repitilia: snakes & lizards. Aves birds. Mammalia: Quadrapeds.
Mammals: warm blooded. Hair provides insulation for metabolic heat. Mammary glands. Homeo thermic(regulates internal body temperature). Monotremes lay eggs. Female incubates eggs in burrow. Marsupial young being in female's body but born premature.
Mammales with placentas: most mammls. Extraembryonic membranes are modified for internal development in uterus. The chorion is fetal portion of placenta & the unterine wall grows maternal portion. These exchange nutrients, oxygen and wastes between featal and maternal blood.
Expands cerebral hemispheres. Long gestation allows more time for learning.
Primates: Opposable thums and finters. Nails becomes claws. Eytes moved to the front of the head for steroscopic vision,;slection against strong sense of smell. Single birth. Ardipitheus ramidus(4.4 mya) not erect.
Australo Pithecines: smaller teeth and skull. Erect.
Australopithecus anamensis (4mya) -human legs
afarensis (lucy)(3.4 mya) bipedal-erect. Canine teeth smaller than apes. Brain size half of ours. After stasis, branched up to ten species by 2 mya.
africanus: slender: found in Southern Africa.
Robustus and boisei.
-ate meat. No tool usage
aetiopicus(2.5mya)-likely ancestral to robustus and boisei
Homo habilis (dany man)(1.6-2mya): 45% larger brain. Smaller teeth. Divison of labor, speech and culture.
Homo erectus (1.9 and 0.5 mya) -larger brains, bigger brow, flatter face. -advanced tools, used fire, returned tobases. Striding gait allowed migration.
Modern humans: 300000 ybp, archaic homo sapiens evolved.
Multiregional continuity: each population evolved into modern humans, where each population derive from h.Erectus ancestors in each location.
Out-of-Africa: advance h.Sapiens migrated to Europe and Asia (100000 ybp0). Interbred or supplanted others.
Naenderthalensis(200000ybp) larger musculature.
Homo sapiens:(cro-magnon)Resemble humans in face and brain size. Societal living, language, and drawings. Arignacian tools.