← Back to the archive★ Support my pages
DD-101Naturealso ScienceFiled Last updated

Lucky Stripe

Short answer: Why zebras are striped has been debated since Darwin and Wallace. The best-supported explanation today is protection against biting flies such as horse flies (tabanids), which spread disease.

In a 2019 PLOS ONE study, Tim Caro and colleagues filmed flies around zebras and horses in the UK and found flies approached zebras but failed to slow down and land as often as on horses; horses wearing striped coats also got fewer landings. Other ideas, such as camouflage, social signaling and heat control, have weaker support. The footage shows zebras grazing and close-ups of flies.

VideoWrite-up2 sources
More like this★ Support my pagesCite this file

What should you know about Lucky Stripe?

Quick facts. Each one stands alone and has a stable ID you can cite.

  1. Why zebras have stripes has been debated since the 19th century.

    DD-101-F01 · Write-up · Exhibit A (Old question)

  2. The leading explanation is protection from biting flies.

    DD-101-F02 · Write-up · Exhibit B (Biting flies)

Video transcript: Lucky Stripe: Biting Flies Struggle to Land on Zebras

Zebras are known for their distinctive black and white stripes but this pattern serves as more than just a visual spectacle. The stripes on a zebra's coat have a functional purpose they act as a natural form of insect repellant. DID YOU KNOW? Studies suggest that the black and white stripes may help deter biting flies, such as horseflies, which are known to transmit diseases. Stripes create a visual disruption making it difficult for these blood sucking insects to land on the zebra's skin. This adaptation is a clever example of how animals use their physical characteristics for both protection and survival in their natural environments. NOW YOU KNOW!

Burned-in captions, read frame by frame (see transcript.md) · 30.1s Reel ·

Video coming soonLucky Stripe · Instagram Reel
Lucky Stripe: Biting Flies Struggle to Land on Zebras Instagram Reel · · 30.1s

The write-up

Biting flies struggle to land on zebras. Horse flies approach zebras but fail to slow down and land.

  1. Exhibit A

    Old question

    Why zebras have stripes has been debated since the 19th century.

  2. Exhibit B

    Biting flies

    The leading explanation is protection from biting flies.

  3. Exhibit C

    Failed landings

    Flies approached zebras but often failed to land.

  4. Exhibit D

    Striped coats

    Horses in striped coats got fewer landings too.

  5. Exhibit E

    Other ideas

    Camouflage and heat control have weaker support.

Questions people ask about Lucky Stripe

What's the leading explanation for zebra stripes?

Supported by field studies.

Source: Write-up · Exhibit A (Old question) · Wikipedia: Zebra

How long has the question been debated?

Darwin and Wallace argued over it.

Source: Write-up · Exhibit B (Biting flies) · Wikipedia: Zebra; PLOS ONE: Benefits of zebra stripes: Behaviour of tabanid flies around zebras and horses (2019)

What did flies do near zebras?

They didn't slow down properly.

Source: Write-up · Exhibit C (Failed landings) · PLOS ONE: Benefits of zebra stripes: Behaviour of tabanid flies around zebras and horses (2019)

What happened to horses in striped coats?

Stripes worked on horses too.

Source: Write-up · Exhibit D (Striped coats) · PLOS ONE: Benefits of zebra stripes: Behaviour of tabanid flies around zebras and horses (2019)

Which idea has weaker support?

Evidence favors flies.

Source: Write-up · Exhibit E (Other ideas) · Wikipedia: Zebra

Test Your Knowledge

All quizzes →

5 questions, all from this case file. Answers are revealed instantly.

  1. What's the leading explanation for zebra stripes?

    1. Deterring biting flies
    2. Attracting mates only
    3. Hiding at noon
    4. Freezing cold
    Show the answer

    Answer: A. Deterring biting flies Supported by field studies. Source: Write-up · Exhibit A (Old question) · Wikipedia: Zebra

  2. How long has the question been debated?

    1. Since the 19th century
    2. Since 2019
    3. Since the 1990s
    4. It never was
    Show the answer

    Answer: A. Since the 19th century Darwin and Wallace argued over it. Source: Write-up · Exhibit B (Biting flies) · Wikipedia: Zebra; PLOS ONE: Benefits of zebra stripes: Behaviour of tabanid flies around zebras and horses (2019)

  3. What did flies do near zebras?

    1. Failed to land well
    2. Landed more
    3. Ignored them
    4. Bit only legs
    Show the answer

    Answer: A. Failed to land well They didn't slow down properly. Source: Write-up · Exhibit C (Failed landings) · PLOS ONE: Benefits of zebra stripes: Behaviour of tabanid flies around zebras and horses (2019)

  4. What happened to horses in striped coats?

    1. Fewer fly landings
    2. More bites
    3. No change
    4. They overheated
    Show the answer

    Answer: A. Fewer fly landings Stripes worked on horses too. Source: Write-up · Exhibit D (Striped coats) · PLOS ONE: Benefits of zebra stripes: Behaviour of tabanid flies around zebras and horses (2019)

  5. Which idea has weaker support?

    1. Heat control
    2. Fly protection
    3. Neither
    4. Both proven
    Show the answer

    Answer: A. Heat control Evidence favors flies. Source: Write-up · Exhibit E (Other ideas) · Wikipedia: Zebra

Cite this case file

Easterling, Marcus. "Lucky Stripe." The Detail Department (DetailEnjoyer), case file DD-101, last updated Nov 30, 2023. https://detailenjoyer.com/case/lucky-stripe/

Permalink: https://detailenjoyer.com/case/lucky-stripe/ · Last updated

Markdown version

Cite a single fact by its ID, for example DD-101-F01 → https://detailenjoyer.com/case/lucky-stripe/#DD-101-F01