Evolution of human
Lecture No 530-V
„Nothing in biology makes sense except in the light of evolution.“
Theodosius Dobzhansky
Time scheme of EvolutionTime scheme of EvolutionPrecambrian eraPrecambrian era
4.6 billionyears ago
4.0 billionyears ago
3.5 billionyears ago
2.5 billionyears ago
1.5 billionyears ago
multicellular eukaryotes
unicellular eukaryotesprokaryotes
Time scheme of EvolutionTime scheme of Evolution
• Palaeozoic era (supercontinent Pangea)• 500 million y. a. – plants, fungi, animals
colonize land (Cambrian period)• Mesozoic era = “Dinosaurs period”• 250 million y. a. – first mammals• Cenozoic 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 Time scheme of Human EvolutionEvolution
• 35 million years ago – dawn ape:
anthropoid Aegyptopithecus• 5-7 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 EvolutionTime scheme of Human Evolution
Homo ergaster
skeleton (AL 288-1) Australopithecus afarensis, cast from Museum national d'histoire naturelle, Pari
The fossil Lucy
Important Characters of Human Evolution
• Size of brainAustralopithecus 400cm3 = Homo sapiens 1 300cm3
• Shape of jawbone - shorter and reduced jawbone
= flat face, chin protrusion, change of dentition
• Upright bearing, bipedal locomotion → skeleton
• Reduced 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. sapiens
Height and upright bearing
Reduced sexual dimorphism
Three Models for the Origin of Human
• Monogenesis 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 ModelMonogenesis Modelfor the Origin of Humanfor the Origin of Human
100 000 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 Multiregional Model for the Origin of Humanfor the Origin of Human
1-2 million years ago
Proofs:• mitochondrial DNA divergence – greater
genetic diversity within African populations
• studies of DNA from the Y chromosome
• Recent DNA evidence suggests that several haplotypes of Neanderthal origin are present among all non-African populations
Mitochondrial Eve
Comparison 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 Evolution
• The 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:
• Obesity• Immunity disorders – allergy
autoimmunity
tumors - leukemia
Primeval human• In close contact with nature• Frequent change of
dwelling• Exposed to frequent
infection stimuli
(infection the most frequent cause of death)
- Extreme physical activity
- Alternation of satiety period with starving period
Australopithecus afarensis
Homo erectus
Homo neanderthalensis
LiteratureLiterature
Biology, 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