How do we know?
↻ One of the pages with a moving picture
A scientist watched garter snakes follow trails.
- Each flick picks up tiny bits of scent from the air, water or ground.
- The tongue brings them back to a special smell organ in the roof of the mouth.
- The two forked tips sample two spots at once, a bit like your two ears.
- So a snake can tell which way a smell is stronger and follow a trail.
A scientist watched garter snakes follow trails. If one tongue tip slipped off the trail, the snake turned away from that tip, back on track.
Smell is only one sense. Some snakes can also sense heat: many pit vipers, pythons and boas have heat pits.
There are more than 4,000 kinds of snakes, but none live in Iceland. It is too cold there, just like Greenland and Antarctica.
Wow number
4,000+ There are more than 4,000 kinds of snakes!
Myth or fact?
Snakes can sting with their tongues. Myth. Their tongues are only for sensing.
Some snakes can sense heat. Fact. Many pit vipers, pythons and boas have heat pits.
Think about it
Why would a snake need to find its way to food without seeing it?
Where in the world?
Iceland where no snakes live. It is too cold, like Greenland and Antarctica — 64.9631° N, 19.0208° W.
Where these facts come from
Every number on page 60, and who measured it
This page explains how a snake's tongue carries smells to the roof of its mouth.
The fascinating world of tongue-flicking — Zoo Atlanta
zooatlanta.org/the-fascinating-world-of-tongue-flicking
We checked it on 31 October 2026
This page tells us about the scientist who watched garter snakes follow trails.
Explainer: why do snakes flick their tongues? — The Conversation, where university scientists write news stories
theconversation.com/explainer-why-do-snakes-flick-their-tongues-29935
We checked it on 31 October 2026
This page tells us how many kinds of snakes there are and where none live.
Snakes: Super senses, stretchy jaws and deadly venom — The Natural History Museum in London
nhm.ac.uk/discover/snakes-senses-stretchy-jaws-deadly-venom.html
We checked it on 31 October 2026
This page tells us about the heat pits some snakes have.
Do Snakes Have Ears? And Other Sensational Serpent Questions — The Smithsonian's National Zoo
nationalzoo.si.edu/animals/news/do-snakes-have-ears-and-other-sensational-serpent-questions
We checked it on 31 October 2026
Has this changed?
Why snakes flick their tongues is not going to change.
New kinds of snakes are still being found, so the number of kinds may go up.
Words from this page
- forked
- Split into two points at the end, like a snake’s tongue.
- heat pit
- A small hole on a snake’s face that senses warmth.
Try it!
Find out which side a smell comes from.
1. With a grown-up, dab a little lemon juice on a cotton swab. 2. Close your eyes. A friend holds it near your left or right cheek. 3. Sniff. Can you tell which side it’s on?
What happens: it’s hard! A snake’s two tongue tips make telling sides easier.
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