Golden mantella frogs go fluorescent at Chester Zoo
27 January 2014 Last updated at 08:19 GMT
Have a look at these tiny frogs that glow!
Conservationists at Chester Zoo have been injecting a harmless silicone gel that gives these endangered frogs a fluorescent colour stripe.
It's to make it easier to keep an eye on the golden mantella frogs, which are are only 2cm long.
The team is now heading to Madagascar in Africa to inject wild frogs there.
The plan is to watch where the frogs go and work out the areas of forest that should be protected to help conserve them.