it discuss about the different mechanism that leads to evolution of a species or organisms

1. Mechanisms of Evolution
Understanding How Species Change
Over Time
Presented by: [Your Name]

2. What is Evolution?
• • Evolution is the change in the heritable traits
of biological populations over generations.
• • It explains the diversity of life on Earth.
• • Driven by several natural processes.

3. Key Mechanisms of Evolution
• 1. Natural Selection
• 2. Genetic Drift
• 3. Gene Flow (Migration)
• 4. Mutation
• 5. Non-Random Mating

4. Natural Selection
• • Proposed by Charles Darwin
• • Individuals with favorable traits survive and
reproduce
• • Traits become more common over
generations
• Example: Peppered moths during the
Industrial Revolution

5. Genetic Drift
• • Random changes in allele frequencies
• • Strongest in small populations
• Types:
• - Bottleneck Effect: Sharp population
reduction
• - Founder Effect: New population from few
individuals

6. Gene Flow (Migration)
• • Movement of genes between populations
• • Increases genetic variation
• • Can introduce new traits
• Example: Migration of animals between
isolated populations

7. Mutation
• • Changes in DNA sequences
• • Source of new genetic variation
• • Can be beneficial, neutral, or harmful
• Example: Sickle cell trait providing malaria
resistance

8. Non-Random Mating
• • Mating is not random – individuals select
mates
• • Affects which traits become common
• • Includes sexual selection
• Example: Peacock tails attracting mates

9. Combined Effects
• • These mechanisms often work together
• Example: Mutation + natural selection
• Real-world case: Antibiotic resistance in
bacteria

10. Recap and Summary
• • Evolution occurs through multiple
mechanisms
• • Leads to adaptation and speciation
• • Explains biodiversity on Earth
• Think About: How do these processes affect
humans today?

11. Questions & Discussion
• • What examples of evolution can you observe
around you?
• • How does understanding evolution help in
medicine and conservation?

12. References
• • Campbell Biology, 11th Edition
• • National Geographic
• • Khan Academy – Evolution