Which of these is an example of evolution?

Question

BlackTom AI · Accepted Answer

Natural selection, a mechanism of evolution, requires heritable variation in a trait that causes differential reproductive success so that alleles for the beneficial trait increase in frequency over generations.

Relevant concepts:
- Evolution = change in allele frequencies in a population over time.
- Natural selection = non-random process where individuals with heritable traits that confer higher fitness leave more offspring.
- Genetic drift/bottleneck = random changes in allele frequencies due to chance events.
- Mere presence/absence of organisms or ecological replacement is not necessarily evolution unless allele frequencies change.

Step-by-step reasoning:
1. Identify the key elements in each choice: Is there heritable variation? Does it lead to differential reproductive success? Will allele frequencies change?
2. Option c: “A bird with a bigger beak able to get more energy from seeds passing more of its genes on than its counterparts.”
   - Variation: beak size differs among individuals (heritable trait).
   - Advantage: bigger beak allows more energy intake, increasing survival/reproduction.
   - Outcome: individuals with bigger beaks pass more genes to the next generation so the alleles for larger beaks increase in frequency.
   - Therefore this is a clear example of natural selection driving evolution.
3. Option a: A species unable to eat food in one area and competitors populate it.
   - This describes local extinction or competitive exclusion and community change, not necessarily a change in allele frequencies within the original species due to selection. It’s ecological replacement rather than documented evolution of the species.
4. Option b: One species cannot tolerate warmer water while others can.
   - This is a statement of difference in tolerance, not the process that changed allele frequencies; it could be an outcome of past evolution but as stated it’s an observation, not an example of evolution occurring.
5. Option d: A tidal wave wipes out half a turtle population and the other half repopulate.
   - While bottlenecks can cause genetic drift (a mechanism of evolution), the choice merely describes a population reduction and repopulation without specifying a change in allele frequencies or selection. The stem’s best, explicit example of evolution by selection is c.

Why c is correct: it explicitly links a heritable trait to increased reproductive success and the passing on of genes, matching the definition of evolution by natural selection.

Conclusion: The correct answer is c, matching the provided answer.

Which of these is an example of evolution?单项选择题

类似问题

What is known scientifically about transitional forms in the fossil record?

Gabby prefers using Instagram over TikTok, just like her mom. This is a good example of evolution at work. True or false? Choose the best answer.

What factor is NOT a characteristic resulting from the domestication of the silkworm?

Which of the following statements concerning the Mesozoic or the post-Mesozoic world is FALSE?

There are two fossils of marine reptiles that captured the moment of birth. To which of the groups below do they belong?

Which of the following is an example of a trait that may have been adaptive for our ancestors but is not adaptive today?

Which statements about Urbilateria are true. (multiple statements may be correct)

Humans evolved from simpler organisms.

更多留学生实用工具

智能学习助手

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