The Grand Canyon Squirrels
Storyboard Szöveg
- The Abert's squirrel
- The Kaibab squirrel
- Speciation of the Grand Canyon Squirrels
- There are Abert's squirrels living in Grand Canyon, AZ. This is before a geographical barrier is made by the Colorado River.#160;
- The Colorado River created Grand Canyon, which created a geographical barrier between this species. Now, some of the Abert's squirrel population live in the south rim and some of them live in the north rim. Since, this new barrier caused a geographical isolation, these two of the same species cannot interbreed with each other, in other words, they are reproductively isolated.
- The population that ended up in the south rim stayed as Abert's squirrels and have a large range.#160;
- However, over thousands of years of isolation, the population that ended up in the north rim diverged into a new species, called the Kaibab squirrels. They have a much smaller range and have similar size, shape, and diet as the Abert's squirrels.#160;
- In conclusion, the mechanism of evolution was a geographical isolation that occurred about 10,000 years ago. Reproduction isolation led by this caused the Abert's squirrels to diverge into two different species, which are Kaibab squirrels and Abert's squirrels.#160;
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