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Natural Selection and Genetic Modification - Coggle Diagram
Natural Selection and Genetic Modification
Evolution
Slow, continuous change in an organism's inherited characteristics
Theory of Evolution
Useful characteristic alleles are more likely to be passed on to next generation
Better adapted individuals more likely to survive and breed
Selection pressures
Disease
Competiton for resources
Predation
Genetic variation due to randomly mutated alleles
Individuals without advantageous allele more likely to die and not reproduce
Advantageous allele to become more common in the population
Evidence
Resistance to antibiotics
Antibiotics kill bacteria
Bacteria mutate to become resistant to antibiotics
New advantageous allele leads to survival of bacteria
Reproduces more times via binary fission
Antibiotic resistance spreads and becomes more common in bacteria population
All non-resistant bacteria die and leave only resistant bacteria
Antibiotics Resistance = Example of natural selection that we can observe
Fossils
Any trace of an animal that lived long ago; usually found in rocks
Arranging fossils in chronological order allows gradual changes to be observed
Provides evidence of evolution because shows how species have changed and developed over billions of years
Darwin and Wallace
Charles Darwin
Came up with the theory of natural selection
Spent 5 years on a voyage on HMS Beagle studying plants and animals
Noticed variation within species
Found that those with the most suited characteristics were more likely to survive
Noticed characteristics could be passed to offspring
Wrote his Theory of Evolution by Natural Selection
Alfred Russel Wallace
Worked at the same time as Darwin
Came up with the idea of natural selection independently of Darwin
He and Darwin published papers together, acknowledging each other's work
They didn't always agree on mechanisms of natural selection
Observations provided lots of evidence for natural selection
Warning colours used by butterflies was an evolved trait
Darwin's book 'On the Origin of Species' is more prominent because Darwin gave lots of evidence and
expanded upon it
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Influence on Modern Biology
All life changes through the process of evolution
We are all descended from a common ancestor
Key areas directly affected
Classification
If all living organisms descended from one common ancestor, we're all related in some way
We now classify organisms based on how related they are
Antibiotic resistance
Importance of finishing the course of drugs to prevent resistant bacteria spreading
Constantly develop new antibiotics to fight newly evolved resistant bacteria
Conservation
Understanding the importance of genetic diversity
It helps populations to adapt to changing environments
Led to conservation projects to protect species
Evidence for human evolution - fossils
Fossils give us clues about our ancestors
Human fossils
Human Evolution
Evidence for human evolution - stone tools
The Pentadactyl Limb
Classification