This surprising mammal fossil is giving scientists something to chew on

Study the questions and tasks

Work through the material below, or start the interactive practice above to complete an attempt. Try the exercises before opening any answer or transcript sections, then use them to review your work.

Practice level

C2. Try this level if you can follow the instructions and understand most of the language; choose an earlier level if you need more support.

Question formats

Single choice

How to approach this practice

Read the passage for its main idea, then return to the relevant sentence or paragraph for each question. Base answers on the passage.

1. Question 1 · Single choice

   Choose one answer.

   What is the article’s central claim about the fossil?

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   1. It demonstrates that Jurassic mammals closely resembled modern mammals.
   2. It reveals early mammalian traits through exceptional preservation and imaging.
   3. It proves that all Jurassic predators possessed platypus-like anatomy.
   4. It establishes X-ray fluorescence as the only reliable fossil method.
   Check answers and explanations

   Answer

   It reveals early mammalian traits through exceptional preservation and imaging.

   The article emphasizes both preserved traits and the methods that reveal them.

   Together, the fossil and the analysis suggest that important features of mammalian biology were already present among ancient relatives long before mammals became familiar in their modern forms.

2. Question 2 · Single choice

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   What does “this degree of preservation” refer to?

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   1. The fossil’s unusually large size
   2. The specimen’s chemical brightness
   3. The survival of bones and soft-tissue impressions
   4. The museum’s extensive fossil collection
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   Answer

   The survival of bones and soft-tissue impressions

   The phrase points back to the survival of bones and soft-tissue impressions.

   The specimen attracted attention because both its bones and impressions of soft tissue survived.

3. Question 3 · Single choice

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   Why does the author mention the modern platypus?

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   1. To identify Megacauda’s closest living relative
   2. To illustrate the fossil’s combination of traits
   3. To explain why the fossil lived in water
   4. To contrast Jurassic and modern body sizes
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   Answer

   To illustrate the fossil’s combination of traits

   The comparison highlights the fossil’s distinctive mixture of anatomical characteristics.

   Its pelvis, hind limbs, and tail resemble those of a modern platypus, while its sharp teeth suggest that it was a predator.

4. Question 4 · Single choice

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   What relationship exists between the dark rock and the imaging technique?

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   1. The rock enhanced ordinary photographic contrast.
   2. The rock caused researchers to abandon imaging.
   3. The similar darkness necessitated chemical imaging.
   4. The rock preserved only the animal’s soft tissue.
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   Answer

   The similar darkness necessitated chemical imaging.

   The dark materials created the problem that spectroscopy subsequently addressed.

   Its bones are very dark, as is the surrounding rock, so ordinary photographs cannot easily distinguish the skeleton from the shale.

5. Question 5 · Single choice

   Choose one answer.

   How is the article organized overall?

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   1. Chronologically, from excavation to museum closure
   2. By contrasting two competing evolutionary theories
   3. From significance and evidence to method and implications
   4. By listing researchers before describing the fossil
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   Answer

   From significance and evidence to method and implications

   It moves from discovery and significance to anatomy, technical difficulty, and broader implications.

   In that sense, the specimen is valuable for two reasons: its preservation records a combination of mammalian traits, while modern imaging methods make those traits visible.

6. Question 6 · Single choice

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   What can reasonably be inferred about the researchers’ conclusions?

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   1. They observed Megacauda alive in its habitat.
   2. They derived behavioral claims indirectly from physical evidence.
   3. They rejected all anatomical interpretations as speculative.
   4. They considered preservation irrelevant to behavioral analysis.
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   Answer

   They derived behavioral claims indirectly from physical evidence.

   The evidence supports cautious reconstruction rather than direct observation of behavior.

   Early fossil mammals are exceedingly rare, and this degree of preservation allowed researchers to infer aspects of the animal’s behavior as well as its structure.

7. Question 7 · Single choice

   Choose one answer.

   What does the phrase “push evidence ... deep into the past” indicate?

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   1. The traits emerged relatively early in evolutionary history.
   2. The traits disappeared before the Jurassic period.
   3. The fossil was physically moved deep underground.
   4. The innovations were restricted to modern mammals.
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   Answer

   The traits emerged relatively early in evolutionary history.

   The findings place mammalian innovations earlier than previously documented evidence.

   Those findings push evidence for these evolutionary innovations deep into the past, at least to the middle Jurassic.

8. Question 8 · Single choice

   Choose one answer.

   Why does the article identify the fossil’s approximate size at the outset?

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   1. To suggest the animal was domesticated
   2. To establish an accessible sense of scale
   3. To prove size determined its diet
   4. To distinguish it from every modern mammal
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   Answer

   To establish an accessible sense of scale

   The comparison provides an accessible scale before introducing technical significance.

   A fossil roughly the size of a Chihuahua is offering scientists an unusually detailed glimpse of mammalian life during the middle Jurassic, about 165 million years ago.

What to review next

Find the words that support each answer. For a mistake, compare the question with the evidence and identify the detail or inference you missed.

A focused practice result shows how you did on these tasks. Use several activities across skills to decide what to study next; one practice score does not certify an overall CEFR level.

Before you practise: a worked example

Look for evidence in the text. Separate what the writer says from what you already know about the topic.

The library normally closes at six, but on Fridays it stays open until eight. When does it close on Friday?

The answer is eight. But introduces an exception to the normal closing time, so the first time mentioned is not the answer.

This teaching example is separate from the scored questions. After your test, compare any mistakes with the explanation and revisit the topic before trying again.