# Let's Go Bats: answers and explanations

Cambridge IELTS 7, Test 1, Reading Passage 1

Source: Passage, questions and answer key from Cambridge IELTS 7, Test 1, Reading Passage 1. © Cambridge University Press & Assessment. Used for educational practice. Explanations and evidence notes are written by Testmigo.

## Answer key

| Q | Answer | Proof |
| --- | --- | --- |
| 1 | B | Deep-sea fish and whales have little or no light by day or by night. ... Fish and dolphins that live in extremely muddy water cannot see |
| 2 | A | our mammalian ancestors probably only managed to survive at all because they found ways of scraping a living at night. |
| 3 | A | But the daytime economy is already heavily exploited by other creatures such as birds. |
| 4 | E | much of our scientific understanding of the details of what bats are doing has come from applying radar theory to them. |
| 5 | D | weapons designers adapted it for the detection of submarines. ... Both sides in the Second world war relied heavily on these devices |
| 6 | phantom | like the referred pain in a phantom limb. |
| 7 | echoes | The sensation of facial vision, it turns out, really goes in through the ears. ... are actually using echoes of their own footsteps and of other sounds |
| 8 | depth | for example to measure the depth of the sea under a ship. |
| 9 | submarines | adapted it for the detection of submarines. |
| 10 | natural selection | or rather natural selection working on bats, had perfected the system tens of millions of years earlier |
| 11 | radio waves | It is technically incorrect to talk about bat 'radar', since they do not use radio waves. |
| 12 | mathematical theories | But the underlying mathematical theories of radar and sonar are very similar |
| 13 | zoologist | The American zoologist Donald Griffin |

## Why these answers are right

**1. B.** You need the paragraph that lists other animals which cannot navigate by sight. Paragraph B names night-flying insects, deep-sea fish and whales living with little or no light, and fish and dolphins in muddy water that cannot see, so B holds these examples.

**2. A.** This item asks how early mammals avoided extinction. Paragraph A says that while dinosaurs dominated the daytime, our mammalian ancestors probably only survived because they found ways of scraping a living at night. Surviving by living at night is the explanation, so A is correct.

**3. A.** The question asks for the reason bats hunt at night. Paragraph A explains that the daytime economy is already heavily exploited by creatures such as birds, and that natural selection favored bats that make a go of night hunting instead. That reason appears only in A.

The why and the trap for questions 4 onwards are free with an account on the [answers page](https://testmigo.com/ielts/reading/lets-go-bats/answers).

[Practice Let's Go Bats](https://testmigo.com/ielts/reading/lets-go-bats)