The wood which is drifted in the ocean water for centuries and moulded as sculptures with the help of hydrodynamic processes such as beating the waves, scrubbing by shells, corals, sand, stones etc, along with twisting in the currents and decaying in the process, is known as fossilized driftwood. Obviously, they will be centuries old.
Many of the wooden pieces which are tree trunks, stumps or roots, when drifting across the turbulent seas, become more resilient. Having traversed vast distances, what is left of a tree is its sturdiest part which has weathered much inclemency. When a selected few out of them are picked up, cleansed and unwanted parts are removed. They resemble a good extent, familiar shapes of birds animals, reptiles, amphibians, fishes etc