Biological Evolution

Species

Group of related interbreeding organisms

Artificial Selection

Selective breeding

Natural selection

New species is brought into existence by

Changes in the environment

Competition between & within species

Variation naturally occuring within species

Excess of procreation over the number the environment can support

Fossil

Evidence of ancient life

Mutation

Permenant change in genetic material

Ladder of progress

Organisms are always getting better

Principle of divergence

How modern evolutionary biology fits Darwin's work?

Scientific advances supported, refined,expanded his work

All variations arose through mutations in genes

Discovery of structure of DNA extended evolution

Changes in base sequence of DNA underlies new traits

Uniformity in genetic code is evidence for Darwin's theory

How religion creationist & advocates tackle evolution?

Isn't evolution just a theory that remains unproven

Withstood the test of time & thousands of scientific experiments

Haven't been proven wrong yet

Darwin's theory as an exampe of scientific method

He observed for 5 years

Hypothesized

Common ancestor

Tested his hypthesis by breeding & comparing data

Formulated a theory that can be falsified

Published his results in his book "Origins of life"

Evolution versus survival of the fittest

Survival of fittest a mechanism that drives evolutionary change

Presented theory of evolution

Species arose from a common descendent as a result of divergence

Evidence for evolution

Found on Galapogos Islands

Varied in beak sizes on different parts of the island

Artificial selection had a marked effect on the form of domesticated plants and animals

If Humans could breed over a period of time ,what changes would occur in nature over millions of years

When environment reaches a large capacity,forces of struggle for existence between & within species

If changes occur in physical environment, changes will transmit features that are advantageous

Individuals variations will be favoured by sets of circumstance & give rise to varieties in succesive generations

Darwin's misunderstandings

Humans evovled from Apes

Evolution is a ladder process with organisms constantly getting better

Evolutionary theory is about the origin of life

Evolutionary theory is false because the fossil record is incomplete

Evolution is not science because its not obsevable or testable

Evolution and religion are incompatible

Clarifing his misunderstandings

What is better under one condition may not be under another

Evolutionary theory is the way life changes after its origin

There must be specific conditions for fossilization

Its both observable and testable

Fossil record

Study of living species

Artificial selection

Genetic mutation

Science & religion are 2 different things

Science-natural causes explain phenomenon

Religion deals with beliefs beyond natural world

What Darwin didn't know

What is the ultimate source of variation?