Evolution

• The development of life in geological time.

• Today evolution refers to the origin from earlier life forms – the process that has transformed life from its earliest beginning to the vast diversity that has and does exist today.

The Big Bang Theory

George Lemaitre

First proposed ‘big bang theory’

Edwin Hubble

All galaxies are moving away

from us

The Hubble Telescope

3.9 billion years old

Where did life come from?

Special Creation

•Life created by a super natural being at a particular time

ArchbishopUssher

• 1654• Life began on

earth at 9am, 23rd October, 4004 BC

• He based this on calculations form the bible

William Paley (1802)

• The fact that such complicated things exist is evidence for the existence of a creator!

Panspermai

• Life arrived form outer space

Comet storms

Fred Hoyle

Life originated in outer space and came to earth riding on light

beams

Svente Arrhenius

• Life originated in the form of spores and was then driven through space by the pressure of light from the sun.

Watson and Crick• Crick – life

has evolved twice.

• Once from molecules to intelligent people elsewhere.

• Once from bacteria to humans

Evidence

• Experiments have shown that when ammonia, methane and carbon dioxide are mixed with ice crystals in a vacuum and UV light applied – hundreds of organic molecules are formed.

• Presence of bacteria in meteorites

• Survival of bacteria in space

20 million year old BeeBacterai found in the resin were still

alive!

Cosmozoan Theory

Life arrived from outer space

• UFO’s

• Cave drawings of dinosaurs

• Kangaroos in SA

Britney Spears

• Alien?

Spontaneous Generation

Aristotle (384BC-322BC)

• Believed that certain particles contained an ‘Active ingredient’ which could produce life

Van Helmont (1577-1644)

• Recipe for spontaneous generation of mice

• Dirty shirt

• Dark cupboard

• Wheat grains

• Active ingredient - sweat

Francisco Redi

• This experiment asked questions about spontaneous generation

Pasteur

• Disproved the idea of spontaneous generation (1860)

Biochemical Evolution

• The formation of organic molecules from inorganic material

Oparin – The Russian

J.B.S. HaldaneThe Brit

Jupiter

• Atmosphere

• Methane• Ammonia• Hydrogen• Water

vapour• CO2

Miller and Urey

Miller and Ureys Experiment 1953

Fred Hoyle

• Life assembling from inorganic substances is –

• “as improbable as a tornado blowing through a junk yard and assembling a 747”

Protobionts

Protobionts

• Proto – First• Biont – life form• These are specialized droplets whose internal

chemical characteristics differ markedly form their surroundings.

• Capable of growth by engulfing other droplets• These were probably the precursors to

prokaryotes• RNA could provide means of transferring

information

Bacteria – Clostridium tatani

First life forms appear on earth around 3.5 billion years ago

Prokaryote

Bacteria - Prokaryotes

So how do we get from Prokaryotes

to Eukaryotes?

Endosymbiotic Theory

Amoeba – Protist

First Eukaryotes around 2.1 billion years ago

Euglena

• Could chloroplasts have once been free living prokaryotes?

Paramecium - Protist

Were mitochondria once free living prokaryotes

Theories for the origin of life

• Special creation

• Panspermia

• Cosmozoan

• Stready State

• Biochemical Evolution

• Spontaneous

Modern science evaluates theories in many ways. For a theory to be scientifically

credible it must:

– fit with the known facts– Overlap with other known scientific theories– Lead to testable predictions– Not rely on supernatural explanations

So which fit with scientific theory

• Special creation• Panspermia• Cosmozoan• Stready State • Biochemical Evolution• Spontaneous

– fit with the known facts– Overlap with other

known scientific theories

– Lead to testable predictions

– Not rely on supernatural explanations