Question

1

The ocean is full of amazing creatures. Unfortunately, it's also full of plastic, which is harmful to the animals that live there. There are about 171 trillion pieces of plastic floating in the sea, according to a study published in the journal PLOS One in 2023. That's bad news for marine animals, such as deep-diving whales, which mistake the plastic for food and eat it, leading to health problems.

2

How do whales mix up plastic and prey? A team at the Duke University Marine Lab, in North Carolina, has been looking into this question. The team published research that explains why some deep-diving whales mistake plastic for food. The research suggests that it all comes down to echolocation: a biological process that allows whales to "hear" objects in the darkest depths of the sea through echoes.


Hunting by Sound

3

Some types of whales, including sperm whales and beaked whales, hunt in the deepest parts of the ocean. Very little light reaches those depths, so it's too dark for whales to see. But they can hear. To navigate their surroundings and hunt for food, deep-diving whales use sounds produced by echolocation.

4

First, the whales emit a sound. That sound produces echoes, which bounce off nearby objects. Ideally, those echoes would allow the whales to identify nearby prey. The echoes bounce off prey animals, like squid—but they also bounce off inedible objects, like garbage. The scientists found that garbage and prey cause similar echoes. To the whales, they "sound" the same, tricking the creatures into eating trash.

5

The scientists gathered oceanic debris such as bottles, bags, and rope, all of which are frequently found in the stomachs of whales. The team bounced sounds off these objects at sonic frequencies similar to those used by echolocating whales. A machine measured the strength of each echo. The team compared these echoes to those produced off the bodies of prey animals, like squid. The plastic items returned echoes similar in strength to those from prey animals.

6

Greg Merrill, a marine biologist, is the lead author on the study. He was "kind of unsurprised" by the results. "We knew they were eating the garbage," he said. "There had to be a reason."


Finding a Solution

7

The study has dangerous implications. Plastic can build up in whales' stomachs, preventing food from passing through their bodies and leading to serious illness or death. "Plastic pollution impacts animals that are so far away from our daily lives," Merrill says. "This problem is really big."

8

The good news is that everyone can play a part in reducing marine plastic pollution. "People need to make real changes in their daily lives, and advocate for the types of solutions that we need to address this issue," Merrill says. Advocacy can be as simple as writing local leaders like your mayor or governor, or asking school leaders if they could "make decisions that are more sustainable."

Lillian Stone, © TIME For Kids. All rights reserved. Reproduced with permission.

5Question 5
Which excerpt conveys the author's perspective on the urgency of environmental pollution?
A.
"'Plastic pollution impacts animals that are so far away from our daily lives,' Merrill says. 'This problem is really big.'" (paragraph 7)
B.
"The scientists gathered oceanic debris such as bottles, bags, and rope, all of which are frequently found in the stomachs of whales." (paragraph 5)
C.
"The good news is that everyone can play a part in reducing marine plastic pollution." (paragraph 8)
D.
"'We knew they were eating the garbage,' he said. 'There had to be a reason.'" (paragraph 6)

Answer 1

A

This quote directly expresses the seriousness and scale of the problem—calling it "really big" and noting it affects animals far from our daily lives—conveying urgency.