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NATURAL SELECTION. There are 2 variations of the beetles, green and red. The birds prefer eating the green beetles. Over generations the red beetles increase in population because they are not eaten by the birds. More survive to produce more offspring. Generations later….

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There are 2 variations of the beetles, green and red.

The birds prefer eating the green beetles.

Over generations the red beetles increase in population because they are not eaten by the birds.

More survive to produce more offspring.

Generations later….

Over time the red beetles have been selected over the green beetles

So what happens to the birds now?


Natural selection simulation
Natural Selection Simulation

mutation

  • http://phet.colorado.edu/en/simulation/natural-selection

  • Why are there different colors?

  • Why do wolves eat white rabbit (in the equator environment)?

  • Why do # brown rabbits increase over time?

    4) What is it called when the # brown rabbits increases over time?

    5) What if the environment changed to the arctic?

Brown are camouflaged

or move faster

Brown survive, reproduce & their babies are brown

Evolution

The white rabbits would survive better and

the # white bunnies would increase



Who was charles darwin
Who was Charles Darwin?

  • British scientist that in 1859 published The Origin of Species

  • Stated that all life today came from a common ancestor

  • Change from one to many is called evolution

  • This happens by a process called natural selection.

  • http://www.youtube.com/watch?v=nMgLF8n4DnA


Darwin

Galapagos

Voyage of H.M.S. Beagle, 1831 - 1836

  • 90 feet of ship, 74 people living together for 5 years...


PHYSICAL: This moth mimics an owl’s eyes

BEHAVIORAL: This monkey is using tools to get food

CHEMICAL: this orchid smells like a female bee



Why does this not work?

Change through use and disuse


Natural Selection’s Explanation

Ancestors had different neck lengths

Through natural selection, longer necks survived and passed on their genes.

Eventually all giraffes had long necks.


  • 225 Million Years Ago the continents were together making a super continent called Pangaea

  • The continents split and populations were separated.

  • This increased the variety of living things because they were in new environments,which would select for specific adaptations and isolated these species from reproducing with original form.



ONE Ancestor Many Varieties

  • What are the different types?

  • What could cause all the variety?

http://www.youtube.com/watch?v=sCEeefdaRcw


Common Ancestor-

We did not come from monkeys, we just share a common ancestor


Adaptation
Adaptation

  • the evolutionary process where a population becomes better suited to its environment.

    • This process takes many generations.

  • A feature which is especially important for an organism's survival.

    • For example, the adaptation of horses' teeth to the grinding of grass

      • Flat teeth (due to genetic mutation) chew grass better


How does evolution work
How does Evolution Work?

  • Natural Selection- survival of the fittest

    • Organisms best suited to their environment

  • Natural selection is the result of four features of living systems:

  • 1) variation – differences in the population because of genetic mutation

  • 2) inheritance - parents pass on their genetic mutations to their offspring

  • 3) selection - some organisms reproduce more (fittest) than others

  • 4) time – happens over time, takes many generations


Evolution
Evolution

  • the change in the inherited traits (passed on from parents to offspring) of a populationover many generations.

    • These traits could be:

      • physical (teeth shape)

      • chemical (ability to use sun for energy)

      • behavioral (run fast).

  • This change is caused by mutations in the genes.

  • http://www.youtube.com/watch?v=yVqJ_mQazik


Theories on life
Theories on Life

  • Theory of Evolution

  • Science

  • Based on evidence

  • Creationism

  • Religion

  • Based on faith


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