About 950 species of spiny, globe-shaped echinoderms living on the seabed of every ocean. They crawl slowly on tube feet and mostly graze on algae.
Quick answers
What is it?Echinoderm
Carnivore?No, herbivore
Dangerous?Can be
Their sharp spines protect them, and in some species the spines are venomous.
Domesticated?No
Awake when?Night
Hibernates?No
Kept as a pet?No
Do people eat it?Yes
Its roe is prized, especially in Japan, where uni sells for up to ¥40,000 a kilogram.
At a glance
Found inOceans
HabitatCoast, Open ocean
ColoursBlack, Purple, Red
SizeTiny
LegsNone
Covered inSpines
Lives ingroups
Lives for30–200 years
Lays eggs
In the wild
- Where it lives
- All oceans, from the tidal zone to the deep sea.
- What it eats
- Mainly algae; also slow-moving or fixed animals such as sponges.
Did you know
Its mouth has five teeth and is called Aristotle's lantern.
Left unchecked by predators such as sea otters, urchins can strip the seabed into “urchin barrens”.
Often confused with
On these lists
Sources
Last reviewed
Play
Could you have guessed it?
A photo, a few hints, one guess. Same 438 animals.
