Your SlideShare is downloading. ×
Introduction to Theory of Evolution
Upcoming SlideShare
Loading in...5

Thanks for flagging this SlideShare!

Oops! An error has occurred.


Introducing the official SlideShare app

Stunning, full-screen experience for iPhone and Android

Text the download link to your phone

Standard text messaging rates apply

Introduction to Theory of Evolution


Published on

Published in: Education, Technology

  • Be the first to comment

  • Be the first to like this

No Downloads
Total Views
On Slideshare
From Embeds
Number of Embeds
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

No notes for slide


  • 1. Chapter 25: EvolutionBiology: Mrs. Neistadt
  • 2. Changes Over Time: *Most species change over time. This slow, gradual change is called Evolution ____________________. Evidence shows the first living creatures were single-celled organisms living in the oceans 3 billion years ago. *Many species have become extinct. Extinct species were once living, but no longer exist.
  • 3. Jean Baptist Lamarck In the 1800s scientists were studying and discovering __Fossils . A fossil is the remains of an organism that lived long ago. Jean Baptist Lamarck proposed one of the first theories of evolution. He thought organisms developed traits by using or not using parts of their body.  Example: Giraffes Incorrect!
  • 4. Charles Darwin In 1831 an Englishman named Charles Darwin took a trip on the HMS Beagle. He was to map the coast of South America. He stopped on the Galapagos Islands where he began a study that would turn scientific study in a new direction. Darwin discovered the various Galapagos Islands had different species of animals. He noticed 13 species of finches. Each finch had a different beak, specialized to find food on its island.
  • 5. Charles Darwin Charles Darwin spend 20 years thinking about his discoveries. *In 1859, Darwin wrote the book, “The Origin of Species” to explain his theories on evolution.
  • 6. *Four Points to Darwin’s Theory: *Overproduction *Competition *Variations or Adaptations *Survival of the Fittest
  • 7. Charles Darwin
  • 8. Genetic Variations: Darwin did not know HOW genetic traits were passed on. *A gene pool is the combined genetic information of all members of a population. By studying the gene pool of a population, scientists can see how variations in traits are passed to offspring.
  • 9. *Events That Can CauseEvolution: *Natural Selection *Evolution can only occur when *Mutation an event causes changes in the gene pool.*Genetic Drift
  • 10. Natural Selection *Natural Selection is the way that organisms best suited to an environment survive
  • 11. Mutation *Mutation: If a mutation is harmful the organism may die before passing on the gene. If the mutation is helpful, the organisms live and pass the gene on.
  • 12. Genetic Drift Genetic Drift is changes within a gene pool that occurs due to random events, or when individuals leave or join the population.
  • 13. 3 Types of Evolution: Divergent Convergent Coevolution Evolution Evolution Different Types of Evolution
  • 14. Your turn…Create a graphic organizer to Compare the 3 types of evolution: Divergent Convergent Coevolution Use Internet research and/or your textbook Pg398 to help you.