Directions: Use the information provided and your knowledge of Life Science to answer the following questions. Show all work where necessary.
Directions: Use the information provided and your knowledge of Life Science to answer the following questions. Show all work where necessary.
In African savannas, giraffes live in open woodlands where trees are often tall and food can be scarce during dry seasons. While all giraffes share similar features, there is variation in neck length among individuals. Some have slightly longer necks than others.
Scientists from the African Wildlife Ecology Institute measured how neck length affects feeding height and survival. They found that giraffes with longer necks can reach leaves higher in acacia trees, where shorter individuals cannot feed - especially when lower vegetation dries out.
Giraffe Category | Average Neck Length (m) | Average Feeding Height (m) | Survival Rate (%) |
|---|---|---|---|
Short-necked | 1.7 | 2.0 | 60 |
Medium-necked | 2.1 | 2.6 | 75 |
Long-necked | 2.5 | 3.2 | 90 |
Even small variations in neck length can provide a feeding advantage. When food is limited near the ground, giraffes with longer necks can reach leaves that others cannot. These individuals are more likely to survive, reproduce, and pass on their genes, increasing the frequency of long-neck traits in the population over time.
This example provides strong evidence that variation among individuals contributes to survival and reproduction advantages. The inherited trait (neck length) interacts with environmental conditions (food height availability), illustrating natural selection in action.
Make a claim, provide the evidence, and explain your reasoning for the statement:
“Giraffes with longer necks have an advantage in reaching food and surviving during droughts.”
Respond with your claim, evidence from the table and graphs, and reasoning that connects the evidence to the claim.
Refer to the table and graphs in the Giraffe Neck Length and Feeding Advantage resource.
Describe the relationship between neck length, feeding height, and survival rate.
What advantage do giraffes with longer necks have?
How does neck length variation show both inheritance and difference among giraffes?
Explain how neck length helps giraffes survive in their environment when food is scarce.