SPANGLER SCIENCE

EVOLUTION

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PPT-EVOLUTION

EVOLUTION- NOTES

TERMS:

Theory-  A well tested concept that explains a range of observations. 


Evolution- A gradual change in species over time.

          Slow change.   Diversity of life. 

          Populations accumulate inherited traits over time.


Gradual Evolution- slow steady change by small steps.

Puntuated Equilibrium- quick change between long time without change, no steps.


Species- Group of similar organisms that can survive and reproduce         successfully.

        New species evolve due to isolation- not able to reproduce with             previous species connected with. 

        Species adapt to new or changing environment.


Variation- range of characteristics (traits) ie: size, color

        variation is due partially by genes and part by environment.


Population- group of organisms; same species, same area, and same time.


*remember: organism, population, community


Adaptation- Variations that make the organism better suited to the environment.  Better to survive and reproduce. 

Characteristics that help the organism successful for finding food or shelter.

Noticeable differences.


Natural Selection- Pressure on population; 4 basic needs: food, water, air & shelter.

Populations best suited for the environment will survive. 

Works through steps of overpopulation, variation, competition/adaptation and selection/survival.



Darwin- Studied many varieties of species of organisms.

wrote book The Origin of Species

Fossils- dead organisms buried in sediment (rock and soil particles)

provides evidence of evolution occuring.

provides clues of past and new species of organisms.

remains preserved and helps record time of organisms.

1800’s began to study fossils. 

rocks showed the earth is very old. showed many extinct species and beginnings of species.



Sedimentary Rock- part of the rock cycle.

layered by age (time), oldest lower and newest above.


Earth history- processes same today as in centuries past.

Catastrophic occurances happen to disrupt normal process.

ie: volcano, earthquakes, typhones....

Geological layers and radioactive dating places the earth at 4.6 billion years old. Life at 3 billion years.


Organisms’ change or become extinct due to adapting, or not adapting, to environment. Natural selection.

*Environment changes play a part with organisms altering genetically.


Branching Diagram- see the relationship of organisms from past to present.

Helps in classification of species due to similarities.


fossils2.jpg

PH Making fossils

PH Fossil layers

PH Rock cycle

PH Continental drift



  

  

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