How Did The Galapagos Islands Die Around The Dry Season Of 1977
Why did the finches of the Galapagos Islands die around the dry season of 1977? This has been an important question lately. The answer to this question actually starts a year before in the dry season of 1976. In this season there was a drought. The temperature was higher than usual, and the rainfall was minimal. Actually no rain fell. This drought led to a chain of events that ended up with the finches dead.
The first part of the chain occurred when the drought caused the plants to not produce as many seeds. The finches fed on the plants’ seeds and were a crucial part of their diet. In wet 1977 there were only 100 cactus seeds compared to the normal amount of around 500. The tribulus plant produced only 240 seeds in wet 1977 compared to its usual of around 700. On the island the tribulus plant had the most seeds, but the seeds were harder to …show more content…
Because the plants didn’t produce as many seeds the finches couldn’t eat as much as they used to. Among others, the finch gf36 proved this link. Throughout the year (1976-1977) gf36 foraged consistently for food. In wet 1976 Gf36 was 16.57g. In dry 1977 gf36 was 12.59g. That’s a 4g decrease in weight. This happened to other finches as well.
The lack of food and weight loss eventually caused the finches to die. In Wet 1976 there was a total of 60 finches. The drought hit in dry 1976, which led to the lack of seeds, weight loss, and eventually death. This chain of events caused there to be only 10 finches in dry 1977. But how did these 10 finches survive?
The 10 finches were able to survive thanks to their beak variation. These birds had a longer beak which scientists found allowed them to crack open the harder seeds like the tribulus. Beak length seems to be inherited because it’s an individual trait like height in humans. There is not much evidence to support this claim though because we don’t know who the parents of the offspring
The first part of the chain occurred when the drought caused the plants to not produce as many seeds. The finches fed on the plants’ seeds and were a crucial part of their diet. In wet 1977 there were only 100 cactus seeds compared to the normal amount of around 500. The tribulus plant produced only 240 seeds in wet 1977 compared to its usual of around 700. On the island the tribulus plant had the most seeds, but the seeds were harder to …show more content…
Because the plants didn’t produce as many seeds the finches couldn’t eat as much as they used to. Among others, the finch gf36 proved this link. Throughout the year (1976-1977) gf36 foraged consistently for food. In wet 1976 Gf36 was 16.57g. In dry 1977 gf36 was 12.59g. That’s a 4g decrease in weight. This happened to other finches as well.
The lack of food and weight loss eventually caused the finches to die. In Wet 1976 there was a total of 60 finches. The drought hit in dry 1976, which led to the lack of seeds, weight loss, and eventually death. This chain of events caused there to be only 10 finches in dry 1977. But how did these 10 finches survive?
The 10 finches were able to survive thanks to their beak variation. These birds had a longer beak which scientists found allowed them to crack open the harder seeds like the tribulus. Beak length seems to be inherited because it’s an individual trait like height in humans. There is not much evidence to support this claim though because we don’t know who the parents of the offspring