BiodiversityHaving more species

A. A. C. Sumedha

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Going to be discussed…

• Evolution• Darwin’s idea• Natural Selection• What Mendel found• Gene and DNA

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Early Idea was All species had been exactly as they were in present. No evolution.

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Current Idea by Charles Darwin Evolution

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Modern humans(Homo sapiens)appear about2 secondsbefore midnight

Recorded humanhistory begins1/4 secondbefore midnight

Origin of life(3.6–3.8 billionyears ago)

Biological Evolution of Life

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Charles Darwin

Showed all this evidence favored the evolution of species from a common ancestor

Proposed the

mechanism for evolution

Natural Selection6Sumedha Athawuda

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Natural SelectionSumedha Athawuda

Greatest threat to polar bear is melting of sea ice

- > Will cause them to eradicate from earth

Eg: Climate change and extinction of species

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Gregor Mendel

Inheritance due to transmission of discrete particles (Now called Genes)

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DNA(DeoxyriboNucleic Acid)

• Later found genes are contain in the DNA (DNA is in cell)

• Genetic code found in DNA is same for a species

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Summary

• Evolution is due to - > Natural Selection (By Charles Darwin)

• Gene inherit properties from generation to generation

(By Mendel)

• DNA contain the Genes

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