HSP3U – Unit 1
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AnthropologyHuman Evolution
Evolutionary Theory
•Charles
Darwin 1809-1882
•Published
Origin of the
Species (1859)
Islands – observed
different species of finches
•Galapagos
•Controversial
!
Darwin’s Theory – Natural Selection
•Heritability:
Organisms inherit characteristics from
their parents
2.Variation:
there is a lot of variation within a species
2.Environmental
Fitness: Those traits that allow an
individual to survive to reproductive age – to pass on to
offspring
Darwin’s Finches
•An
example of
Variation
Peppered Moth UK – example of natural
selection
•White
•Food
and Black moths (Variation)
source for birds
Industrial Rev. most moths – white better camouflaged against white lichen
(Enviromental Fitness)
•Before
Rev – coal dust turned environment
black, now black moths better camouflaged.
Black moths now surviving to reproduce and
pass their colour to next generation
(Heritability)
•Industrial
•Now,
most moths are black (natural selection)
Evolution –
evidence
•Physical
•Look
Anthropologists
at:
1. Fossil, bone, stone
remains (using dating
techniques)
2. Microscopic analysis –
pollen, scratches on
bone
3. Experiments – flake
stone techniques
Human Evolution
Human Evolution
•hominid:
is any
member of the biological
family Hominidae (the
"great apes"), including
the humans, chimps,
bonobos, gorillas and
orangutans
Hominids
Habitual Bipedalism
– to
habitually walk on two
legs. Humans only
primate with this
adaptation
•Bipedalism
•What
had to happen for
us to stand up straight?
Bipedalism continued
•Structural
changes required for
us to walk upright:
•S-shaped
spine
•Double arched foot
•Pelvis – shorter and wider
•More gluteus muscles
•Fewer head / neck muscles –
therefore a bigger brain
Advantages of being bipedal
•Free
hands for
carrying
•Can
walk longer
distances
•Can
have a
continuous good view
of surroundings
Disadvantages of
being bipedal
•Highly
dangerous birthing
process
•Offspring
very dependent
and weak because the
skull must grow outside of
the womb
Hominids and
Brain Size
•Humans
have
the largest
brain for our
body mass
compared to
other mammals
Hominid (human), Primate differences:
Primates
Social
structures
Dominance Hierarchies
Silverbacks and alpha
males in a group
Grooming
Related to the hierarchies
Stress release
Hominids /
Humans
Pair Bonding AND
Group Living
Humans are the only
primates to have both
social characteristics
simultaneously
Hominid (human), Primate differences
Primates
Reproduction Estrus cycle (in heat)
No choice of when to
mate
Who gets to mate when
ties into dominance and
grooming hierarchies
Hominids /
Humans
No estrus cycle
Choice in when to
mate
Hominid (human), Primate differences
Primates
Mother –
Infant
relationship
Long infant
dependency
compared to other
mammals
Important in learning
survival skills and
culture
Hominids /
Humans
Longest infant
dependency
period of all primates
Hominid (human), Primate differences
Primates
Communication
Facial displays, call,
touch
Hominids /
Humans
Speech centre in the
brain
Humanity and
our Variations
•Our
bodies are essentially
50 000 years old.
•Now
culture, not physical
evolution enables us to
adapt very quickly to a
changing environment
- Cultural construct –
does not physically exist
•Race
Skin Colour - Legitimate Explanations for
Human Variation
•Sunlight
is the best source of
vitamin D (necessary for
healthy bones)
•Light
skin absorbs vitamin D
and burns more easily than
darker skin
Paler skin is
found in areas further from the
equator where there is less
sunlight (environmental
Fitness)
•Skin
colour (variation)
Skin Colour - Legitimate Explanations for
Human Variation
Darker skin provides better
protection from UV rays
•
•Darker
skin is found in areas
closer to the equator where
there is more and stronger
sunlight (environmental
Fitness)
•Skin
colour (variation)