# They Don't Age! (DD-322)

> Hydras are freshwater animals a few millimeters long, with a tubular body and a mouth ringed by stinging tentacles that catch tiny prey. They can regenerate a whole body from a small fragment. Studies of Hydra vulgaris found that its death rate does not rise with age, so it shows no measurable aging, which makes it a model for research on regeneration and longevity. The footage shows a hydra under a microscope.

- Department: Nature (also Science)
- First published: 2024-09-11
- Last updated: 2024-09-11
- Permalink: https://detailenjoyer.com/case/they-dont-age/
- Author: Marcus Easterling (DetailEnjoyer), The Detail Department

## Quick facts

- **DD-322-F01**: Hydras are a few millimeters long. _(Write-up · Exhibit A (Size))_
- **DD-322-F02**: Tentacles catch prey. _(Write-up · Exhibit B (Tentacles))_

## Write-up

A hydra can regrow a whole body from a small piece. Some hydras show no measurable signs of aging.

1. **Size**: Hydras are a few millimeters long.
2. **Tentacles**: Tentacles catch prey.
3. **Regeneration**: They regrow from fragments.
4. **No aging**: Hydra vulgaris shows no measurable aging.
5. **Research**: They are studied for longevity.

## Related case files

- [Argyroneta Aquatica (DD-670)](https://detailenjoyer.com/case/argyroneta-aquatica/): I linked another tiny freshwater animal

## Reel vs. record

- **Note**: None needed.

## Video: They Don't Age!: A Hydra Can Regrow a Whole Body From a Small Piece

- Duration: 27.3 s · Published: 2024-09-11
- File: https://detailenjoyer.com/assets/videos/C_zMY0UpnvB.mp4

### Transcript

Did you know? Hydras are tiny, freshwater organisms known for their simple tubular bodies and remarkable regenerative abilities, despite their small size, typically just a few millimeters long. Hydras are fascinating because they can regenerate entire bodies from just a small fragment of tissue. They have a central mouth, surrounded by tentacles that they use to capture prey, like small aquatic creatures. Hydras are also intriguing to scientists because they don't seem to age, showing no signs of the usual aging process, making them a key subject in studies of regeneration and longevity. NOW YOU KNOW!

## Questions & answers

**Q: Where do hydras live?**  
A: Ponds and lakes. _(Source: Write-up · Exhibit A (Size) · Wikipedia: Hydra (genus))_

**Q: How long are they?**  
A: Tiny. _(Source: Write-up · Exhibit B (Tentacles) · Wikipedia: Hydra (genus))_

**Q: What can they regrow from?**  
A: Remarkable. _(Source: Write-up · Exhibit C (Regeneration) · Wikipedia: Hydra (genus))_

**Q: What do tentacles do?**  
A: Stinging cells. _(Source: Write-up · Exhibit D (No aging) · Wikipedia: Biological immortality)_

**Q: Do they show signs of aging?**  
A: Hydra vulgaris. _(Source: Write-up · Exhibit E (Research) · Wikipedia: Hydra (genus); Wikipedia: Biological immortality)_

## Sources

- [Wikipedia: Hydra (genus)](https://en.wikipedia.org/wiki/Hydra_(genus))
- [Wikipedia: Biological immortality](https://en.wikipedia.org/wiki/Biological_immortality)

## Cite this case file

Easterling, Marcus. "They Don't Age!." The Detail Department (DetailEnjoyer), case file DD-322, last updated Sep 11, 2024. https://detailenjoyer.com/case/they-dont-age/