Jellyfish – The Dominant Species
Read Jellyfish – The Dominant Species and check the IELTS Reading answers. Jellyfish have become the curse of beach holidays, permeating every ocean on the globe, thriving in the Arctic and the tropics. In an ever-changing world where other species struggle to endure, jellyfish populations are on t…
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Jellyfish have become the curse of beach holidays, permeating every ocean on the globe, thriving in the Arctic and the tropics. In an ever-changing world where other species struggle to endure, jellyfish populations are on the rise. To the untrained eye, these creatures drift aimlessly on the oceans' currents and appear benign. In addition, they lack sharp claws, piercing teeth or even a brain. Despite this, they are armed with an amazing arsenal of weapons, especially the stinging power of their tentacles. As a result, jellyfish are among the most-feared, least-understood creatures in the seas.
Vocabulary from this passage
11 words worth learning before you sit the test, each with the sentence it appears in.
- aggregation noun
A cluster of things that have come or been brought together; a collection
The sudden aggregation of jellyfish near the coast disrupted local fishing activities.
- analogy noun
A comparison between one thing and another, typically for the purpose of explanation
The professor used an analogy to explain the complex function of the immune system.
- benign adjective
Gentle and kindly; not harmful to the environment or health
While the chemical appears benign, long-term exposure may have adverse effects.
- eutrophication noun
Excessive richness of nutrients in a lake or other body of water, frequently due to runoff
Agricultural runoff is a primary cause of eutrophication in coastal waters.
- infestation noun
The presence of an unusually large number of insects or animals in a place
The sudden infestation of locusts destroyed crops across the region.
- monoculture noun
The cultivation or dominance of a single species in a given area
The ecosystem shifted from diverse marine life to a monoculture of jellyfish.
- permeate verb
To spread throughout something; to pervade every part of an area or substance
A sense of anxiety permeated the community following the environmental disaster.
- predation noun
The preying of one animal on others; the action of attacking or plundering
Small fish keep jellyfish populations in check through competition and predation.
- proliferate verb
To increase rapidly in numbers; to multiply or reproduce quickly
Without natural predators, the invasive species continued to proliferate unchecked.
- speculate verb
To form a theory or conjecture about a subject without firm evidence
Scientists speculate that rising ocean temperatures are driving the migration.
- stem verb
To stop or restrict the flow or progress of something undesirable
Strict measures were introduced to stem the tide of illegal pollution.
Answers with explanations
- 14. E
The question looks for a **prediction** regarding the **direction** of population spread. The text states that **tropical species are moving towards the poles** and **could move** into subtropical regions, which maps the spread prediction. Answer: E.
- 15. A
The question asks for a description of **physical characteristics**. The text describes what they lack (**claws, teeth, brain**) and what they have (**tentacles**), providing a physical description. Answer: A.
- 16. F
The question asks for the **consequences** of jellyfish as **lone survivors** (monoculture). The text describes how the ecosystem becomes a **desert in terms of biodiversity** and loses other species when jellyfish are dominant. Answer: F.
- 17. G
The question asks for **suggestions to avoid** further invasions. The text lists specific recommendations: **halt to overfishing**, **reducing fertilizer**, and **confronting climate change**. Answer: G.
- 18-19: CE
18: Option C mentions the decline in **Black Sea anchovy**. The text confirms jellyfish **devastated the Black Sea** and fed on **anchovy eggs**, directly contributing to the population decline. Answer: C.
19: Option E mentions **financial hardship** in the fishing industry. The text explicitly links jellyfish to an **economic effect** on the **fishing industry** resulting in **millions of dollars in losses**. Answer: E.
- 20-21: AB
20: Option A suggests a **shortage of small fish** is a cause. The text states **overfishing has removed fish** and explains that **small fish** usually keep jellyfish in check, so their removal allows jellyfish to proliferate. Answer: A.
21: Option B suggests **dumping chemicals**. The text identifies **fertilizer and waste run-off** (chemicals) causing eutrophication, which contributes to **jellyfish explosions**. Answer: B.
- 22. eggs
The sentence says jellyfish eat the [blank] of fish. The text states they feed on **anchovy eggs**. The noun **eggs** completes the sentence. Answer: eggs.
- 23. monoculture
The sentence asks for the name given to the state where jellyfish are the main species. The text defines this state as a **monoculture** of jellyfish. Answer: monoculture.
- 24. nets
The sentence mentions jellyfish damage [blank] used for fishing. The text states they fill **nets**, causing them to **break**. Answer: nets.
- 25. temperature
The sentence refers to understanding facts like the [blank] of the ocean. The text explicitly mentions **ideal water temperature** as a factor to understand. Answer: temperature.
- 26. prevention
The sentence states Richardson believes it is better to direct attention to [blank]. The text quotes him proposing a focus on **prevention** rather than cure. Answer: prevention.