Vredenburg studied the impact of the introduction of rainbow and brook trout on a species of amphibian, the mountain yellow-legged frog (Rana muscosa). After showing greatly decreased frog populations in lakes with trout, he set up an experiment using three categories of lakes: lakes from which he removed trout, lakes that had never had trout, and lakes that still contained trout. He compared the number of adult frogs per 10 m of shoreline in all groups, as shown in the figure. What is the most likely reason that Vredenburg chose to use a large-scale experimental design such as this, rather than a single lake or laboratory experiments?

Question

BlackTom AI · Accepted Answer

To understand why a broad, large-scale experimental design was chosen, we must consider what the question is asking and the nature of ecological interactions.
Option: 'A smaller study would not adequately answer the experimental question.' This statement reflects a common limitation in ecological research: results from a single site or a small number of lakes may not capture the variability across landscapes, species interactions, and environmental conditions that influence frog populations.
First, in a natural setting like lakes with and without trout, multiple factors such as lake size, predator presence, food resources, climate, and historical exposure to trout can differ among sites. A small study risks overgeneralizing findings from one or a few lakes to all lakes, thereby reducing external validity.
Second, random variation and context dependence can obscure cause-and-effect relationships when sample size is limited. By using three categories of lakes (trout-removed, trout-present, and trout-absent) across many lakes, the researcher can better isolate the effect of trout presence on adult frog abundance while accounting for site-to-site variability.
Third, large-scale designs allow for replication, which strengthens inference about causality. If the observed frog declines consistently align with trout presence across diverse lakes, confidence in a causal link rises compared to a single-lake study.
Fourth, laboratory experiments, while controlled, may fail to mimic the complex ecological interactions and stochastic events occurring in natural ecosystems. A large-scale, field-based design provides more realistic evidence about how trout introductions influence frog populations in real-world conditions.
In sum, the justification centers on improving generalizability, controlling for confounding variability, and enhancing causal inference by extending the study across many lakes rather than focusing on a single site or a laboratory setting.

BIOEE1610 Lecture 1: Pre-Lecture Reading Assignment: Ecology and the Science of Ecology.

查看解析

登录即可查看完整答案

类似问题

Why is it challenging to measure the effect of neonicotinoid insecticides on bee's health "in the field" as opposed to "in the laboratory"?

In a consumer society, many adults channel creativity into buying things

Economic stress and unpredictable times have resulted in a booming industry for self-help products

People born without creativity never can develop it

A product has a selling price of $20, a contribution margin ratio of 40% and fixed cost of $120,000. To make a profit of $30,000. The number of units that must be sold is: Type the number without $ and a comma. Eg: 20000

Which of the following statement regarding cost is correct:

Under the assumptions used in cost-volume-profit analysis, as the activity increases:

The CVP and break-even analysis are supported by a range of important assumptions. Which of the following is not an assumption of the CVP:

更多留学生实用工具

考试浏览器助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单