What is Natural Selection and How Does it Work? By Alexander
Table of Contents Mutations
Conclusion
Glossary
Sources
Thanks
Introduction Natural selection is a very important part of evolution and nature. It is a system that decides if a living organism survives or dies out. It is called “Natural Selection” because nature selects which group of a population will survive and which won’t. Mutations are what cause natural selection.
The lighted light bulb is still working because it is the fittest among the light bulbs even though it is not “Natural Selection”.
Mutations Mutation is when a species of living organisms grows a part of them that helps them survive. For example, imagine a species of fish doesn’t have enough water. Many of the fish die, but some manage to survive. A few million years later, one of the fish babies gets rid of the gills and grows lungs because of the lack of water. It also grows feet instead of fins. It mates with another fish and produces babies. The offspring also have feet and lungs and a new species is born. Another example:Imagine there are humans with long legs and short legs.There are hungry bears in their habitat. The humans with longer legs also run faster than the ones with the shorter legs. The ones with the shorter legs become bear food and die out, so then the human species evolves to only have longer legs. Now here's a real example: Darwin's finches. Darwin was a famous scientist who went onto the H.M.S. Beagle to search for new species in the Galapagos Islands. On the expedition he found this amazing bird called a finch. He went onto all of the islands and found out that all of the finches looked different. He thought that all of the finches came from one kind of ancestor finch then slowly evolved into different species, He was right. Millions of years ago when there was only one kind of finch, they all, looked all the same with slightly different body parts. Perhaps some of the finches had long beaks and some had short ones. The ones with the long beaks could probably get to the worms in the trees/ ground and the beaks with short ones couldn’t ,so short beaked finches died out. The ones with the long beaks survived and reproduced. Over time there were finches who could eat seeds and drink nectar as a result of evolution.
This is a chart of some of the animals living over the millions of years.
Conclusion Natural selection is the backbone of evolution. It is proof that evolution actually happens and exists. If the world didn’t have natural selection then all life on earth would vanish. Natural selection allows organisms to adaptations when their environment changes. Natural selection is very important because without it, we will all be extinct by now.
What humans might be in the future.
Glossary
Extinct-A species wiped from the face off the earth.
Population-A group of living things living together
Reproduced-Re-make a copy of your self.
Sources
https://www.youtube.com/watch?v=hOfRN0KihOU
https://www.youtube.com/watch?v=S1t5_iGN0xE
https://www.youtube.com/watch?v=0SCjhI86grU