logo
episode-header-image
Dec 2023
27m 22s

Tooth and Claw: Piranhas

Bbc World Service
About this episode

Adam Hart investigates a frenzied and voracious fish from South America – the piranha! Said to be able to strip their prey to the bone in mere minutes, there are plenty of gruesome tales about the bubbling bloodbaths that occur when shoals of these hardy fish feed in the freshwaters across South America - from up in Venezuela in the Orinoco River, to the Amazon and down to the Paraná River in Argentina. What role did former United States President Theodore Roosevelt have in creating the piranha’s fearsome reputation? And is this reputation misguided?

Adam hears what piranhas are really like, both in the wild and in captivity. He learns about how these fish hunt, the impact that humans are having on them and tries to establish if they really are as bloodthirsty as we’ve been led to believe.

Contributors:

Marcelo Ândrade is a professor at the Federal University of Maranhão in Brazil. He researches the environments that piranha live in and their behaviour, as well as plastic ingestion by piranhas.

Hannah Thomas is the aquarium team manager at Chester Zoo in the UK where they care for 40 red-bellied piranhas.

Presenter: Professor Adam Hart Producer: Jonathan Blackwell Editor: Holly Squire Production Coordinator: Jonathan Harris Studio Manager: Neva Missirian

(Photo: Red-Bellied Piranha, Credit: Ed Reschke via Getty Images)

Up next
Oct 12
The Life Scientific: Edith Heard
Imagine looking at a map of a city you thought you knew inside-out, only to discover a collection of tightly knit neighbourhoods that nobody had ever realised existed... Edith Heard has achieved something rather similar with DNA.Edith is a leading expert in epigenetics: put simpl ... Show More
26m 28s
Oct 5
The Life Scientific: Ginger Kerrick
What do you do when your childhood dream of becoming an astronaut is grounded at the final hurdle?If you’re physicist Ginger Kerrick, you go on to help run the missions instead.After failing the medical of her astronaut application process, Ginger went on to become Nasa’s first n ... Show More
26m 28s
Sep 28
The ocean within us
Here's a little fact you might have heard before: humans are around 70% water. About the same percentage as a sweet potato, incidentally. But what does that actually mean? Sure, there's blood, that accounts for some of it. And the lymphatic system has a fair amount too, sloshing ... Show More
26m 30s
Recommended Episodes
Oct 2025
Could Piranhas Really Eat a Cow in Under a Minute?
Piranhas are very efficient eaters, but their frothing feeding frenzy seen in horror movies is mostly based on a myth started by Theodore Roosevelt. Learn more in this episode of BrainStuff, based on this article: https://animals.howstuffworks.com/animal-facts/piranha-eat-cows.ht ... Show More
8m 6s
Oct 2023
How Do Alligator Gar Work?
These toothy fish are some of the largest in North America. Learn how they've lasted 100 million years in this episode of BrainStuff, based on this article: https://animals.howstuffworks.com/fish/alligator-gar-100-million-years-old-and-still-kicking.htmSee omnystudio.com/listener ... Show More
6m 57s
Aug 2021
The Fish Had Fur, Part 2
Fish covered in thick coats of fur, fish with strange spines, fish with the beard or chin whiskers of a wise old sage… The water offers up many mysteries, and in this episode of Stuff to Blow Your Mind, Robert and Joe explore accounts of furry trout, ancient marvels, otters and f ... Show More
49m 22s
Aug 2021
The Fish Had Fur, Part 1
Fish covered in thick coats of fur, fish with strange spines, fish with the beard or chin whiskers of a wise old sage… The water offers up many mysteries, and in this episode of Stuff to Blow Your Mind, Robert and Joe explore accounts of furry trout, ancient marvels, otters and f ... Show More
40m 19s
Dec 2023
Bolivia’s giant fish intruder
Some people said it was created by Peruvian scientists, that it gorged on the blood of farm animals, that it was a monster. Many myths have grown up in Bolivia around the Paiche, one of the world’s largest scaled freshwater fish which is native to Amazonian rivers of Brazil and P ... Show More
28m 23s
May 2024
The Parrotfish, Part 1
In this episode of Stuff to Blow Your Mind, Robert and Joe discuss the weird and wonderful parrotfish: changers of sex, poopers of sand and – if the myths and legends are true – great friends and a parent of fishes. See omnystudio.com/listener for privacy information. 
57m 45s
Jul 2022
Which are more dangerous: Sharks or humans?
From monster killers of the sea to endangered species - we talk sharks and vocabulary. 
6m 24s
May 2025
From the Vault: The Parrotfish, Part 1
In this classic episode of Stuff to Blow Your Mind, Robert and Joe discuss the weird and wonderful parrotfish: changers of sex, poopers of sand and – if the myths and legends are true – great friends and a parent of fishes. (originally published 5/21/2024)See omnystudio.com/liste ... Show More
58m 3s
May 2025
From the Vault: The Parrotfish, Part 2
In this classic episode of Stuff to Blow Your Mind, Robert and Joe discuss the weird and wonderful parrotfish: changers of sex, poopers of sand and – if the myths and legends are true – great friends and a parent of fishes. (originally published 5/23/2024)See omnystudio.com/liste ... Show More
43m 11s