Mammoth Kill
Read Mammoth Kill and check the IELTS Reading answers. Although it’s hard to imagine in this age of urban sprawl and automobiles, North America once belonged to huge, elephant-like mammoths, camels, bear-sized beavers and other giant beasts, collectively known as ‘megafauna’. Some 11,000 years ago,…
Passage preview
Although it’s hard to imagine in this age of urban sprawl and automobiles, North America once belonged to huge, elephant-like mammoths, camels, bear-sized beavers and other giant beasts, collectively known as ‘megafauna’. Some 11,000 years ago, however, these large-bodied mammals—about 70 species in all—disappeared. Their demise coincided roughly with the arrival of humans on the continent and dramatic climate change—factors that have inspired several theories about the die-off. Yet despite decades of scientific investigation, the exact cause remains a mystery. Now new findings offer support to one of these controversial hypotheses: that human hunting drove these huge megafauna species to extinction.
Vocabulary from this passage
10 words worth learning before you sit the test, each with the sentence it appears in.
- demise noun
The termination of existence, failure, or complete collapse of an entity, species, or institution
The sudden demise of the ancient civilization has puzzled archaeologists and historians for several centuries.
- empirical evidence noun
Information acquired by observation, measurement, or direct experimentation rather than pure theoretical reasoning
Researchers must gather substantial empirical evidence to substantiate their claims about the new therapeutic drug.
- fluctuation noun
An irregular rising and falling or shifting in number, amount, or condition over time
Severe temperature fluctuations in the ocean can completely disrupt the fragile biological equilibrium of coral reefs.
- gestation noun
The physiological process or period of carrying developing offspring in the womb prior to birth
Elephants have the longest gestation period of any land mammal, lasting nearly two full years.
- megafauna noun
The large, giant, or massive animals of a particular region, habitat, or geological period
Pleistocene megafauna, such as the woolly mammoth, became extinct during the last major ice age.
- plausible adjective
Seeming reasonable, probable, or likely to be true based on the available evidence or circumstances
The scientist presented a highly plausible explanation for the unexpected anomaly found in the experimental data.
- proponent noun
An individual who actively advocates for, supports, or argues in favor of a theory, project, or proposal
She is a strong proponent of renewable energy subsidies to combat the escalating threat of global warming.
- urban sprawl noun
The uncontrolled and disproportionate expansion of urban areas into surrounding rural or undeveloped land
Unchecked urban sprawl has severely impacted local ecosystems and fragmented natural wildlife habitats.
- vermin noun
Wild mammals and birds perceived as harmful to crops, carrying disease, or difficult to control
Historical sanitation systems were primarily designed to keep vermin away from dense human settlements.
- viable adjective
Capable of working successfully, surviving, or living under specific environmental or economic conditions
The ambitious conservation program aims to maintain a viable population of the critically endangered snow leopard.
Answers with explanations
- 14. North America
The summary needs a geographic location that **large mammals** inhabited **11,000 years ago**. Paragraph 1 states that these giant beasts once belonged to **North America** and disappeared 11,000 years ago. Therefore, "North America" is the correct two-word completion.
- 15. overkill model
The summary refers to a theory **proposed around fifty years ago by Paul S. Martin**. Paragraph 2 identifies this as the **overkill model**, which emerged in the 1960s and was put forth by Martin. This exact noun phrase is required.
- 16. hunting
The summary states that Martin's theory blames a specific action **by people for mass extinction**. Paragraph 1 details the hypothesis that human **hunting** drove these species to extinction. Therefore, the noun "hunting" perfectly completes the meaning.
- 17. deadly disease
The summary shifts to the second theory, where humans **introduced** something that wiped out the mammals. Paragraph 6 explains MacPhee's suggestion that people introduced a **deadly disease**. This two-word phrase fits the grammatical and contextual requirements.
- 18. empirical evidence
The summary notes that the second theory **lacks** something. Paragraph 6 explicitly states that MacPhee **does not have empirical evidence** for his disease theory. The phrase "empirical evidence" accurately reflects what is missing.
- 19. climate instability
The final theory blames the extinction on a period that experienced **significant** phenomena. Paragraph 7 explains that this epoch witnessed **considerable** (significant) **climate instability**. "Climate instability" correctly completes the gap.
- 20. communities
The text describes how habitat loss led to the **division of the [20]** that mammals had organized. Paragraph 7 states that species that had formed **communities** were forced to **split apart** (division). The noun "communities" is the exact word needed.
- 21. B
The statement claims there is **too little evidence** to support the **hunting theory**. Paragraph 4 introduces **Ross D. E. MacPhee** (B), who argues that the archaeological record contains barely any examples of hunting evidence, making him the proponent of this view.
- 22. C
The statement correlates the **size of the animal** with the **size of the territory it requires**. In Paragraph 7, **Russell W. Graham** (C) explains that large animals need **correspondingly large ranges** for survival, matching this exact feature.
- 23. B
The statement asserts that **humans have been indirectly responsible** for the elimination of species **globally**. Paragraph 6 notes that **Ross D. E. MacPhee** (B) believes humans brought about these extinctions around the world, **but not directly**, perfectly matching the prompt.
- 24. A
The feature links **population estimates** to understanding how mammals became extinct. Paragraph 3 details how **John Alroy** (A) used estimates of the **initial human population** and hunting rates to determine how quickly populations could have been eliminated.
- 25. B
The statement suggests that **scientific examination of fossil remains** may provide proof. Paragraph 6 states that "he" (**Ross D. E. MacPhee**, B) hopes that **analyses of tissue and DNA** from animal remains will eventually reveal the microbes, giving him empirical proof.
- 26. C
The statement says that **environmental changes negatively affected the social groupings** of large species. Paragraph 7 outlines how **Russell W. Graham** (C) explained that climate changes caused regular habitats to disappear, forcing species that had formed **communities** to split apart.