# Lucky Stripe (DD-101)

> 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.

- Department: Nature (also Science)
- First published: 2023-11-30
- Last updated: 2023-11-30
- Permalink: https://detailenjoyer.com/case/lucky-stripe/
- Author: Marcus Easterling (DetailEnjoyer), The Detail Department

## Quick facts

- **DD-101-F01**: Why zebras have stripes has been debated since the 19th century. _(Write-up · Exhibit A (Old question))_
- **DD-101-F02**: The leading explanation is protection from biting flies. _(Write-up · Exhibit B (Biting flies))_

## Write-up

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

1. **Old question**: Why zebras have stripes has been debated since the 19th century.
2. **Biting flies**: The leading explanation is protection from biting flies.
3. **Failed landings**: Flies approached zebras but often failed to land.
4. **Striped coats**: Horses in striped coats got fewer landings too.
5. **Other ideas**: Camouflage and heat control have weaker support.

## Related case files

- [Tigers & Trees (DD-624)](https://detailenjoyer.com/case/tigers-and-trees/): I paired it with another striped animal
- [African Gazelles (DD-138)](https://detailenjoyer.com/case/african-gazelles/): I paired it with more African wildlife
- [Suricata Suricatta (DD-139)](https://detailenjoyer.com/case/suricata-suricatta/): I paired it with more African wildlife
- [Scaly Anteaters (DD-141)](https://detailenjoyer.com/case/scaly-anteaters/): I paired it with more African wildlife
- [Rhinos (DD-142)](https://detailenjoyer.com/case/rhinos/): I paired it with more African wildlife

## Reel vs. record

- **Note**: 'A natural form of insect repellant': I'd say deterrent. The stripes don't repel flies so much as stop them landing properly.

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

- Duration: 30.1 s · Published: 2023-11-30
- File: https://detailenjoyer.com/assets/videos/C0RfHPjO1aG.mp4

### Transcript

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!

## Questions & answers

**Q: What's the leading explanation for zebra stripes?**  
A: Supported by field studies. _(Source: Write-up · Exhibit A (Old question) · Wikipedia: Zebra)_

**Q: How long has the question been debated?**  
A: 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))_

**Q: What did flies do near zebras?**  
A: 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))_

**Q: What happened to horses in striped coats?**  
A: 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))_

**Q: Which idea has weaker support?**  
A: Evidence favors flies. _(Source: Write-up · Exhibit E (Other ideas) · Wikipedia: Zebra)_

## Sources

- [Wikipedia: Zebra](https://en.wikipedia.org/wiki/Zebra)
- [PLOS ONE: Benefits of zebra stripes: Behaviour of tabanid flies around zebras and horses (2019)](https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0210831)

## 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/