| While burrowing, caecilians employ concertina locomotion, lateral undulation, and vermiform locomotion. |
| Most caecilians are terrestrial burrowers, either constructing their own tunnels or living in the litter of the forest floor. |
| The other two layers show angles of 50-60 deg as would be predicted by the hydrostatic skeleton model of internal concertina locomotion in caecilians. |
| The features of aquatic caecilians of the family Typhlonectidae are representative of secondary adaptations. |
| The Jurassic fossil caecilian has small limbs, whereas all living caecilians are limbless. |
| The oldest known frogs, salamanders and caecilians are very similar to their living descendants. |
