Natural Selection

Darwin's Finches

What is Natural Selection?

Natural selection is the process whereby organisms better adapted to their environment tend to survive and produce more offspring. Natural selection is believed to be the mechanism for evolution. Charles Darwin himself was the person who popularized the theory of natural selection by studying the finches of the Galapagos Islands.
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Bon Voyage, Darwin!

Off Darwin went, on a boat to the Galapagos Islands to study the wildlife that is the finches, now famously referred to as 'Darwin's Finches'!

The Same, But Different?

As Darwin island hopped around the Galapagos, he noticed that the finches looked the same, although the size of their beaks massively differed, as well as in size and claws. Darwin concluded that the first arriving finches on the islands have changed over time, although remaining in the finch species.
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Instead of punk rock and tuxedo finches, this is what he actually saw...
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WHAT DOES IT ALL MEAN?

Darwin proposed the theory of evolution by natural selection.

Darwin explains that all species of the planet have formed from a simple life form years before. Natural selection pretty much means that organisms that are best suited to their environment will have the ability to survive, reproduce and pass on the favourable traits on to the offspring.

but wait!

IF GROUPS OF THE SAME SPECIES BECOME SEPARATED FROM EACH OTHER, THE SPECIES CAN DEVELOP A SELECTION OF CHARACTERISTICS TO SUIT THEIR NEW ENVIRONMENT!


HENCE, THE FINCHES BEING AN EXAMPLE OF NATURAL SELECTION! WOO!

RECAP?

So the theory evolution by natural selection pretty much means that the favourable characteristics will be passed on to the offspring, allowing the species to keep reproducing and surviving and so on, coinciding with the environmental features that the species live in.


Therefore, Darwin's finches allows us to see that there are favourable beak sizes and shapes to allow for the bird to find and eat a food source at each island.


One island may have a varity of fruits to eat, so a finch with a large, soft beak would have the characteristic to eat the fruits. Where a finch with a smaller, hard beak may have a better characteristic to pick seeds for the ground.

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let hank give you a little run over, just incase

Watch from 2:35 where he discusses the finches until about 3:35!
Natural Selection - Crash Course Biology #14
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