Researchers Discover Sharks with Unusual Diet

Category: Science/Environment

Listening

Unlocking Word Meanings

Read the following words/expressions found in today’s article.

  1. feed on (something) / fiːd ɑːn / (phrasal) – to eat or consume something
    Example:

    Sharks are known to feed on meat alone.


  2. captive / ˈkæptɪv / (adj) – caught and kept in a cage
    Example:

    We released some of the captive animals into the wild.


  3. run tests on / rʌn tɛsts ɑːn / (phrasal) – to examine someone or something to get more information
    Example:

    Researchers ran tests on the blood of the animal to know more about its health.


  4. disprove / dɪsˈpruːv / (v) – to prove that something is wrong
    Example:

    The research disproves the assumption that sharks’ diet consists of meat only.


  5. inadvertently / ˌɪnədˈvɚtəntli / (adv) – in a manner that is not planned or unintentional
    Example:

    Experts assumed that sharks would inadvertently swallow plants while eating smaller fish.


Article

Read the text below.

A new study revealed that a certain shark species is omnivorous, which means it can feed on both animals and plants.


For three weeks, researchers from the University of California, Irvine, and Florida International University studied bonnethead / ˈbɑːnəthɛd / sharks, relatives of hammerhead sharks. The researchers fed five captive sharks with a diet consisting of 90% seagrass and 10% squid. Afterward, the research team ran tests on the sharks to see how these animals responded to a plant-based diet.


Based on the tests, the sharks were able to fully absorb about half of the nutrients present in the seagrass they ingested. With this result, the research team concluded that the bonnethead sharks are actually omnivorous and not dependent solely on meat. Additionally, the researchers pointed out that other shark species might have the capability to eat and digest plants as well.


Furthermore, these results disproved previous assumptions about the bonnetheads’ diet. More than a decade ago, other researchers found plants in the sharks’ stomachs. Back then, experts thought that the bonnetheads inadvertently ingest seagrass while consuming marine animals.


Despite the noteworthy results of the study, one scientist is not fully satisfied. Gavin Naylor, the director of the Florida Program for Shark Research, finds the research interesting yet insufficient.


Specifically, he is not satisfied with the number of sharks observed and the duration of the experiment. According to Naylor, the sharks’ plant consumption could be brought about by stress. He said that for the results to be more convincing, the team should observe more bonnethead sharks for a period of at least six months.


Viewpoint Discussion

Enjoy a discussion with your tutor.

Discussion A

• Do you agree with Naylor that more research must be done to prove the study’s results? Why or why not?
• Do you think it is important to know about sharks’ diet? Discuss.

Discussion B

• If you were to conduct a research on sea creatures, which one would you study? Why?
• Why do you think it is necessary to do such a research?