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Why Do Finches Survive

Decent Essays
In the Galapagos Islands there is an island named, Daphne Major, this island plays as the host of the Galapagos finches. In 1976 - 1977 there was an absolute near extinction of these finches. This is because of the drought of 1976 and 1977 (see figure 1). While the drought made the Finch population dwindle there was a hidden trait that was helping some survive, and that is beak size. Why did the larger beaks help those fortunate Finches survive? Because the only plants that survived where plants like the Tribulus, which produces hard shelled seeds. While there was an abundance of hard shelled seeds there was a shortage of soft shelled seeds. The finches that had the larger beaks weighed more, for example, survivors weighed approx. 12.5g to 17.5g with beak sizes going from 10.5 to 13.6(for evidence see figure 2. This reduced the population because the Finch’s with the smaller beaks couldn't open the harder seeds and had to scavenge for soft seeds which were very rare. The finches with small beaks, then died from starvation…show more content…
Short beaked finches have less food source because they can’t open hard seeds. Because of that they die off from starvation. Birds with small beaks couldn’t open the hard seeds so they had no food source and struggled to find food they could eat. For evidence of the finches not being able to eat see figure 3.

In conclusion the Galapagos Finches suffered a mass near extinction, although there was a secret weapon the survivors had, beak size. The beak size not only helped the- -survivors survive, but it helped them eat, see figure 2. The rainfall amount (see figure 1) played a major role in the extinction of the finches by taking out the food sources. Lastly the Galapagos finches went to the urge of extinction, but thankfully they were not all taken out by the lessened
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