The common octopus is a highly intelligent, active predator. It even has a secret weapon - special glands produce a venom that it uses to incapacitate its prey!

Mae'r siarc main yma’n cael ei enw o'r pigau o flaen ei asgell ddorsal. Gall ddefnyddio'r pigau yma i amddiffyn ei hun drwy gyrlio mewn bwa a tharo ysglyfaethwr.

Our only venomous snake, the shy adder can be spotted basking in the sunshine in woodland glades and on heathlands.

Selfheal is a low-growing, creeping plant that likes the short turf of grasslands, roadside verges or even lawns. Its clusters of violet flowers appear in summer.

The defensive mechanism of the pill woodlouse is very recognisable - it curls itself into a tight ball, only showing its plated armour to its attacker. It is an important recycler of nutrients,…