The graph shows the range and average of beak depth (the measure from top to bottom of the beak) for seed-eating finches living on an island in the Galapagos between 1976 and 1978.
Information
A graph.Short description, A graph.,Long description,
The graph is titled Average beak size.
In 1976, the smallest beak size was about 5.5 centimeters, and a small number of individuals had a beak of this size. Beak size increased, as did the number of individuals, until it peaked at about 9.5 centimeters. The most individuals had a beak size of about 9.5 centimeters. As beak size continued to increase, the number of individuals decreased. The largest beak size was about 13 centimeters, and a small number of individuals had a beak of this size.
In 1978, the smallest beak size was about 7 centimeters, and a small number of individuals had a beak of this size. Beak size increased, as did the number of individuals, until it peaked at about 12 centimeters. The most individuals had a beak size of about 12 centimeters. As beak size continued to increase, the number of individuals decreased. The largest beak size was about 14.5 centimeters, and a small number of individuals had a beak of this size.
Question
A drought struck the island during these years. Plants that produced small, soft seeds declined dramatically while plants that produced large, hard seeds increased.
What are the ,begin emphasis,three,end emphasis, ,begin emphasis,best,end emphasis, explanations for the difference in beak depth between the two years?
Answer options with 5 options
A.
Beaks grew deeper by cracking bigger, harder seeds.
B.
Deeper beaks allowed finches to survive the drought.
C.
Large, hard seeds require a deeper beak to crack open.
D.
Genes for beak depth were passed on to offspring from surviving finches.
E.
Nature gave the finches deeper beaks during the drought so they could survive.
The three best explanations for the difference in beak depth between the two years are:
A. Beaks grew deeper by cracking bigger, harder seeds.
C. Large, hard seeds require a deeper beak to crack open.
D. Genes for beak depth were passed on to offspring from surviving finches.
The three best explanations for the difference in beak depth between the two years are:
B. Deeper beaks allowed finches to survive the drought.
C. Large, hard seeds require a deeper beak to crack open.
D. Genes for beak depth were passed on to offspring from surviving finches.
To determine the three best explanations for the difference in beak depth between the two years, we need to analyze the information provided in the graph and consider the impact of the drought on the availability of seeds. Here's how you can find the answers:
1. Beaks grew deeper by cracking bigger, harder seeds.
To support or refute this explanation, we need to examine whether the increase in beak depth correlates with the increase in the prevalence of large, hard seeds during the drought. We can see from the information that plants producing large, hard seeds increased during the drought, suggesting that finches may have developed deeper beaks to crack these seeds. Thus, option A seems like a valid explanation.
2. Deeper beaks allowed finches to survive the drought.
To evaluate this explanation, we need to consider whether the deeper beaks provided a survival advantage for the finches during the drought. Since plants producing small, soft seeds declined significantly, it becomes more challenging for finches with smaller beaks to access sufficient food. However, if finches with deeper beaks were more efficient at cracking the larger, harder seeds, they would have had an advantage in terms of finding enough food to survive. Therefore, option B could be a plausible explanation.
3. Large, hard seeds require a deeper beak to crack open.
This explanation is closely related to option A. By examining the increase in the prevalence of large, hard seeds during the drought and the concurrent increase in beak size, it suggests that a deeper beak may be required to crack open these particular seeds. Consequently, option C is likely to be one of the reasons for the difference in beak depth.
As for options D and E, the information provided does not directly support the passing on of genes or nature giving the finches deeper beaks during the drought as explanations for the difference in beak depth. Therefore, these options are less likely to be the three best explanations.
To summarize, the three best explanations for the difference in beak depth between the two years are options A, B, and C.