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.

The alder fly is a blackish invertebrate, with delicately veined wings that it folds over its body like a tent. It can be found near ponds and slow-flowing rivers; the larvae living in the silt at…

The hummingbird hawk-moth migrates to the UK from Southern Europe each year. It can be seen hovering over flowers, feeding with its long proboscis; its wings move so quickly that it 'hums…

An unmistakeable insect of heaths, sand dunes and grasslands, the Emperor moth is fluffy, grey-brown, with big peacock-like eyespots on all four wings. Males can be seen during the day, but…

The distinctive rounded wings of the lapwing are displayed beautifully when it wheels around a winter sky in a massive flock. In spring, these flocks disperse and some birds breed in the UK.…

Like many of our farmland birds, the yellowhammer has declined in number in recent years. Spot this bright yellow bird singing from the top of a bush or fence, or in a mixed-species flock in…

Y dolffiniaid trwyn potel yn nyfroedd Prydain yw’r rhai mwyaf o’u bath – maen nhw angen gallu ymdopi â’n dŵr oer ni! Dyma greaduriaid cymdeithasol iawn ac maen nhw’n fwy na pharod i nofio ochr yn…