Ingo Arndt / Spider fossilized in amber, 50 million years ago.

Paul D Stewart / Photographic reconstruction of Archaeopteryx by Paul D. Stewart. The fossils of this species was from 150 million years ago, and is thought of as a stage between feathered dinosaurs and modern birds.

Juan Carlos Munoz / Pieces of petrified trees / wood, Petrified Forest National Park, Arizona, USA, February 2015.

Jouan Rius / Petrified wood segment, Blue Mesa Badlands, Petrified Forest National Park, Arizona, USA, December 2012.

Adrian Davies / Fossilised fly in Baltic amber. Whole specimen approx 15mm long. Fly approx 5mm.

Philippe Clement / Fossils of belemnites and ammonites on shingle beach near Lyme Regis along the Jurassic Coast, Dorset, UK, November 2012

Philippe Clement / Ammonite fossils (Promicroceras planicosta) on shingle beach near Lyme Regis along the Jurassic Coast, Dorset, southern England, UK, November 2012

Alex Hyde / Velvet Worm (Peripatus novaezealandiae) silhouetted against a leaf, known as 'living fossils', having remained the same for approximately 570 million years, New Zealand, Captive

Alex Hyde / Velvet Worm (Peripatus novaezealandiae) known as 'living fossils', having remained the same for approximately 570 million years, New Zealand, Captive

SINCLAIR STAMMERS / Well preserved fossil of trilobite Dudley locust (Calymene blumenbachii) from the Silurian period, found in the Wenlock Limestone of Wrens Nest Hill, Dudley, Worcestershire.

Paul D Stewart / Chromolithograph illustration of Cromagnon 'Skull of an old man' Plate 1, Section C. Edouard Lartet and Henry Christy. 'Reliquiae Aquitanicae' 1865-1875, Williams and Norgate, London 1875..

Paul D Stewart / Landscape of the Triassic coastal environment with reconstructions of dinosaurs and marine reptiles, 'Dr. Schubert's Naturgeschichte - Geologie, Mineralreich, Palaontologie'. Published in Stuttgart 18...