Evolution of human Lecture No 530-V
Evolution of human
Lecture No 530-V
Nothing in biology makes sense except in the light of evolution.
Time scheme of EvolutionPrecambrian era4.6 billionyears ago4.0 billionyears ago3.5 billionyears ago2.5 billionyears ago1.5 billionyears ago multicellular eukaryotesunicellular eukaryotesprokaryotes
Time scheme of EvolutionPalaeozoic era (supercontinent Pangea) 500 million y. a. plants, fungi, animals colonize land (Cambrian period)Mesozoic era = Dinosaurs period 250 million y. a. first mammalsCenozoic era (after extinction of dinosaurs) 50 million y. a. majority of mammals 5 million y. a. diversion of humans and apes
Plate Tectonics Pangaea Continent Maps
Time scheme of Human Evolution35 million years ago dawn ape: anthropoid Aegyptopithecus5-7 million years ago - diversion of the common ancestor of humans and apes 4 million years ago ape-man: Australopithecus 2.4 million years ago handy man: Homo habilis 1.9 million years ago working man: Homo ergaster 1.8 million years ago upright man: Homo erectus 0.5 million years ago archaic Homo sapiens 0.2-0.3 million years ago Homo neanderthalensis 0.2 million years ago Homo sapiens
Time scheme of Human EvolutionHomo ergaster
skeleton (AL 288-1)Australopithecus afarensis, cast fromMuseum national d'histoire naturelle, PariThe fossil Lucy
Important Characters of Human EvolutionSize of brainAustralopithecus 400cm3 = Homo sapiens 1 300cm3Shape of jawbone - shorter and reduced jawbone = flat face, chin protrusion, change of dentitionUpright bearing, bipedal locomotion skeletonReduced sexual dimorphismhigher weight of male than female: gorilla 2x = human 1,2x Changes in social lifemonogamy with long-term pair-bonding longer care of the young allows better learning and complex behaviour formula
Size of brain and shape of jawbone
Au. africanus, H. erectus & H. sapiensHeight and upright bearing
Reduced sexual dimorphism
Three Models for the Origin of HumanMonogenesis model (out of Africa model) Only the African descendants of Homo erectus, who dispersed from Africa just 0.1 million years ago, gave rise to all the diverse populations of modern humans. All other regional descendants of Homo erectus, including Neanderthals, became extinct without contributing to the gene pool of modern humanity.
Monogenesis Modelfor the Origin of Human100 000 years ago
Multiregional model Modern humans evolved in many parts of the world from regional descendants of Homo erectus, who dispersed from Africa between 1 and 2 million years ago.
Intermediate model - Modern humans may be the result of a migration out of Africa as well as some genetic contribution from non-African archaic groups.
Three Models for the Origin of Human
Multiregional Model for the Origin of Human1-2 million years ago
Proofs:mitochondrial DNA divergence greater genetic diversity within African populationsstudies of DNA from the Y chromosome
Recent DNA evidence suggests that several haplotypes of Neanderthal origin are present among all non-African populations
Mitochondrial EveComparison of neutral mutations could explain differences on possible relationship between different human populations. Homo sapiens originated from a small group of females (or only one female) such called mitochondrial Eve, which delivered to us her mitochondrial genes.Eve lived in Africa. It supports the hypothesis, that the whole mankind originated from only one ancestor (i.e. out-of-Africa theory).
Three Major Stages of cultural EvolutionThe first stage began with nomads who hunted and gathered food on the African grasslands 2 million years ago. They made tools, organized communal activities, and divided labor.
The second stage came with the development of agriculture in Africa, Eurasia, and the Americas about 10 000 - 15 000 years ago. Along with agriculture came permanent settlements and the first cities.
The third stage, the Industrial Revolution, began in the 18th century.Through all this cultural evolution we have not changed biologically in any significant way.Our know-how is stored not in our genes but in the cumulative product of hundreds of generations of human experience, passed along by parents, teachers, books, and, most recently, by electronic means.
Evolution of Human and Modern Medicine Explanation of civilization diseases:
ObesityImmunity disorders allergyautoimmunitytumors - leukemia
Primeval humanIn close contact with natureFrequent change of dwellingExposed to frequent infection stimuli(infection the most frequent cause of death)- Extreme physical activity- Alternation of satiety period with starving period
LiteratureBiology, eighth edition,Neil A. Campbell, Jane B. ReecePearson International Edition, 2008
Unit five: The Evolutionary History of Biological DiversityChapter 34: Vertebrates: Humans are mammals that have a large brain and bipedal locomotionpages 728 733
Thank you for your attention and have a fun with the Croods or the Quest for fire
Pelvis and feed
Homo habilis is the first species for which we have positive evidence of the use of stone tools.*from Homo heidelbergensis, Homo rhodesiensis*