TBOTF Part 2: New Beings on This Earth (Chapter 9 (Variation and…
TBOTF Part 2: New Beings on This Earth
Darwin believed that isolation was the cause of divergence.
He was also struck upon what makes trees divide and how different animals adapt to environments.
Character displacement is when is when two birds who have the same beak size go after the same food. one must die, because it cant get fed or tend for itself.
Both Dolph Schluter and the Grants proved Darwin's theories.
Darwin's theory didn't at any point include hybrids of type of bird.
Raymond pearl based his ideology that hybrids have more to do with evolution than natural selection.
While the say that natural selection and hybrids are equal.
"Non-Adaptive" are finches that choose mates outside of their species.
On that note, Males are territorial and try to keep their females in their protective space.
Grants test to prove Darwin's theory on hoe "all species are organisms"
with Genetic recombination, they provided a better chance of survival for the finches.
The grants ended up taking of the data taken of the years of beak sizes and they put it into the computer.
The Grants proved that The beak width did vary over the years from 8.86- 8.74 with the formula.
Adaptive Radiation is when New Species radiate from their original species
Grants go back to Princeton to analyze their data
When analyzing their data, they found that finches mate with the same type of finch. (small beak with small beak, finches with one small beak and big beak do not breed.
Birds Can have two clutches. A clutch is the number of eggs laid in a nest.
Mr. Grant talks on how in his diagrams and charts, imparticuarly this one, each line represents thousands of generations. And when two roads cross, it is called cosmic parting.
Next, Dobszhansky and Pavlovsky go on to examine fruit flies.
Five years later They concluded that that the Llanos A strain acted in a much different manner compared to the other strains of fruit flies.
Variation and Evolution are very similar to one another.
Variation is practically the smaller changes within a species.
Evolution is the gradual process of time that creates new species. Also, evolution can't happen without variation.
One of Darwin's experiments was that when he put seeds inside of a bottle of salt water even though it represented an ocean.
This also relates to how finches "wandered from island to island over the Galapagos islands.
Darwin Lived thinking that each species of finch stayed on its own separate island, but the Grants proved that they flew from island to island.
Over the decades of research, researchers can predict the the chance of survival for the variations of finches.
Only 1 in 3 finches survived from El Nino from 1982-1983.
Hybrids survive better than purebred El Nino.