Alright, let’s go through the problem step by step:
1. Understanding the Data:
The table given shows the populations of lions, cheetahs, and zebras in Africa in the years 1990 and 2000.
```
Lions: 100,000 (1990) and 47,000 (2000)
Cheetahs: 50,000 (1990) and 7,500 (2000)
Zebras: (Data not provided in the chart, but implied to be a matter of consideration)
```
2. Calculating the Decline in Population:
We can find out how much the populations of lions and cheetahs have declined between 1990 and 2000.
- Lions:
- Population in 1990: 100,000
- Population in 2000: 47,000
- Decline: \( 100,000 - 47,000 = 53,000 \)
- Cheetahs:
- Population in 1990: 50,000
- Population in 2000: 7,500
- Decline: \( 50,000 - 7,500 = 42,500 \)
3. Analyzing the Decline:
The data demonstrates that both lion and cheetah populations significantly declined over the decade:
- Lions: 53,000
- Cheetahs: 42,500
4. Considering the Possible Explanations:
Let’s assess which explanation is best supported by the data:
- Explanation 1: "Lion and cheetah populations compete for the food source of zebras, and lions outcompete cheetahs."
- This explanation does not directly address the common significant decline observed in both predators.
- Explanation 2: "The dwindling zebra population has led to the decline of the predator lion and cheetah populations."
- This explanation suggests that both predatory populations are affected by a decrease in their prey (zebras), which matches the observed declines in both lions and cheetahs.
- Explanation 3: "Overhunting of lion and cheetah populations has led to a decline in the food source population."
- This explanation reverses the cause-effect relationship between predators and prey in an unrealistic manner.
- Explanation 4: "Lion and cheetah populations compete for the food source of zebras, and cheetahs outcompete lions."
- This explanation is similar to Explanation 1 and does not explain the consistent significant decline in both populations.
5. Selecting the Best-Supported Explanation:
Based on the data:
- Decline in lion population: 53,000
- Decline in cheetah population: 42,500
The most plausible explanation supported by this data is: "The dwindling zebra population has led to the decline of the predator lion and cheetah populations." This aligns with Explanation 2.
In conclusion, the extensive decline in both lion (53,000) and cheetah (42,500) populations supports the explanation that a reduced zebra population (prey) impacted predators, leading to their decline. The best-supported explanation is thus:
Explanation 2: "The dwindling zebra population has led to the decline of the predator lion and cheetah populations."
