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This section includes an explanation of the key words and phrases used in the study of fossils.
Amber A resin produced by certain trees since the Jurassic period. When secreted from the bark, resin forms a sticky orange fluid which insects and small creatures can become trapped in. Over time the resin hardens to form Amber, thus preserving itself and any insect or creature within. It was originally believed that mosquitoes trapped in this way, may contain the DNA necessary to resurrect a dinosaur. To date the evidence suggests that DNA could not survive for this length of time.
Ammonite Probably the most commonly associated fossil in the world. Ammonite's are an extinct group of marine 'cephalopod molluscs' that thrived during the Jurassic and Cretaceous period (170 - 65 million years ago). Ammonites consisted of a coiled shell within which the creature lived. These agile predators preyed on smaller marine creatures, including fish and shells. The closest living descendent of Ammonite's are Cuttle fish. To learn more about Ammonites click here.
Angiosperms The collective name for flowering plants which evolved in the Late Jurassic period.
Archean The earliest dated pre-cambrian rock on earth, dating from 3.8 billion years ago.
Belemnite Belemnites were a diverse group of marine creatures that lived in the oceans and sea's across the globe. The creature consisted of a long bullet-shaped shell, within which the squid-like creature lived. Belemnite's were predators, feeding on smaller marine creatures, including fish and shells. In most cases the fossil remains only include the tail guard, located at the end of shell. This guard served as buoyancy and to protect the creature from other predators.
Bipedal A description given to the action of standing, walking or running on two legs.
Bivalve The collective name for molluscs comprising of two valves (upper and lower shell), connected by a organic ligament. These marine creatures were among the first creatures to become widespread across the globe.
Brachiopods A group of marine shellfish capable of living in fresh and saline water. These creatures were among the first to evolve in the Early Cambrian.
Calcium Carbonate A mineral that forms naturally at the Earth's surface. Many creatures including Corals and Clams use this mineral to build and strengthen their skeletons.
Cambrian The period following the Pre-Cambrian, where most marine invertebrates evolved 545 million years ago. Most organisms before this period were not preserved in the fossil record.
Carapace The outer protective shell or shield protecting the body of creatures including crabs and insects.
Carboniferous A period of time extending from 354 - 290 million years ago. During this time large forests developed across the globe, laying down the organic material that would later form the worlds coal supply. At the same time, the first land dwelling vertebrates evolved.
Carnivores The name given to predators that lived on the flesh of other creatures.
Cephalopods A group of marine creatures distinguished by the presence of tentacles, including squid and octopus.
Chalk A rock formed from the deposition of planktonic creatures skeletons which lived in the seas during cretaceous period.
Coal Rock formed from the fossilised remains of plants. The largest volume of coal originates from the Carboniferous period (354 million years ago).
Cretaceous A period of time stretching from 142 - 65 million years ago. The end of this period (the KT boundary) was marked by the mass extinction of the dinosaurs.
Crinoids A group of marine 'sea-lilies' which attached themselves to sea-floor. Crinoids typically include a long thin stem and end with feather like arms arranged in a cup formation.
Devonian A period of time stretching from 417 - 354 million years ago.
Dinosaurs The general name given to describe the land-dwelling reptiles which lived between during the Triassic, Jurassic and Cretaceous period (248 - 65 million years ago).
Echinoderms The collective name given to marine invertebrates, including Echinoids and Crinoids.
Echinoids A group of marine invertebrates which lived on and and beneath the sea bed. Some species are characterised by the presence of spines protruding from a spherical shell, others lived beneath the sea floor, feeding on organic materials trapped within the sediment.
Erosion The term given to describe the action of weathering followed by the transportation of the eroded materials by wind, water, gravity or ice.
Evolution The process given to describe the development of living creatures and plants over time. Evolution requires that life must adapt to its surroundings in order to survive and grow.
Exoskeleton The protective outer shell belonging to creatures such as insects, crustaceans and spiders.
Extinction The resulting term given to mark the end of a species or group of creatures. Extinction usually results from a long-term change in the environment, which subsequently triggers a period of decline and eventual end. The dinosaurs are perhaps the best example of a group of reptiles which faced mass extinction at the end of the Cretaceous period.
Fossil The name given to the remains of trace of creatures or plants which once existed. A fossil is a rock-like copy of the original object, resulting from the replacement of minerals with those of the surrounding rock.
Genus A group/species of organisms which are closely related.
Gondwana A former supercontinent in the southern hemisphere, that later joined with Laurasia to form the single continent of Pangea.
Granite A hard, crystalline rock formed from magma (molten rock).
Graptolites A group of small marine creatures, that existed during the Paleozoic period (545 - 248 Million years ago). These thin, tubular organisms often resemble pencil markings.
Herbivores The collective name for animals which feed on grass and other plant life. During the Jurassic period the mighty Sauropods were among the largest herbivores to walk the earth.
Hydrothermal Vent A volcanic opening on the ocean floor, often located along the mid-ocean ridges. These vents are known to support rich marine organisms, independent of light.
Ice Age A period of many thousands, even millions of years, during which time the Ice Caps extend towards formerly mild/warmer areas of the globe. An Ice Age may follow the dramatic climate change triggered by a large scale impact, such as an asteroid collision.
Ichthyosaurus A group of marine predators which lived between the Triassic and Cretaceous period. These diverse reptiles were shaped like a dolphin and characterised by a long jaw, containing razor sharp teeth and large eyes.
Igneous Rock formed from Magma
Invertebrates The name given to creatures without a backbone (vertebrae).
Jurassic The period of time extending from 206 to 142 million years ago. During this time, the Dinosaurs evolved to become the most powerful and diverse group of creatures to have lived on Earth to that time.
K-T Boundary The event that marked the end of the Cretaceous and the beginning of the Tertiary period, 65 million years ago. This period of time was characterised by a period of mass extinction, widely accepted to have resulted from dramatic climate change. Among the contributors to this change include a six mile wide asteroid which struck the earth, throwing billions of tones of dust into the atmosphere. The name originates from the German 'K' for Kreide, meaning Chalk and 'T' for Tertiary.
Laurasia The former supercontinent that formed in the northern hemisphere. This landmass later joined with the Gondwana to form the mighty Pangea.
Limestone A sedimentary rock formed from the remains of shelly sea creatures.
Mammals A group of warm-blooded, hairy vertebrates which live in many environments, including marine, land and in the air.
Mesozoic The period of time, marked with the great expansion of life in the sea and on the land. The era stretched from 248 to 65 million years ago, and included the evolution and demise of the dinosaurs.
Ordovician A early period of time stretching from 495 - 443 million years ago.
Paleontology The scientific study of fossils, their formation and preservation; the formulation of theories and the history and evolution of ancient life that fossils represent. (Extract from 'The Atlas of the Prehistoric World', Douglas Palmer.)
Paleozoic A period of time stretching from 545 to 258 million years ago, encompassed the Ordovician, Silurian, Devonian and Carboniferous periods.
Pangea The name given to the Supercontinent that existed from the end of the Triassic period. Such was the continent's size, that it stretched from pole to pole, before breaking apart as the Atlantic ocean opened.
Permafrost The term used to describe an area of ground continuously frozen. Only for very brief periods during the summer will the surface thaw.
Permian The final period of the Paleozoic era which stretched from 290 to 248 million years ago.
Plankton A group of tiny microorganisms which live in vast numbers in the oceans and lakes.
Plates Tectonics The term used to describe the process which results in the movement of the earths crust. Over time the semi-molten mantle within the earth creates convection currents, which cause heated rock to rise and cooling rock to descend. At the earths surface this process results in the movement of the continental plates. The resulting movement means that the UK and US are moving apart at roughly the same rate that an average persons finger nails grow.
Precambrian The period of time stretching from the formation of Earth 4.6 billion years ago to the beginning of the Paleozoic period, 545 million years ago.
Pterosaurs The name given to a group of giant flying reptiles which lived between the Late Triassic and Cretaceous periods.
Quadrupedal The collective name given to land dwelling creatures which walk on all four legs.
Quaternary The most recent period of time stretching from 1.8 million years ago to today.
Sandstone A sedimentary rock formed by the deposition of mineral fragments.
Sauropods A group of giant four legged dinosaurs which are characterised by a small head, long neck, immense torso and long tail. The Sauropods were not predators, instead they used their height to feed on the vegetation out of reach to smaller dinosaurs.
Silurian A period of time stretching from 443 to 417 million years ago. The fossil evidence preserved from this period indicates a rapid expansion of marine life, including trilobites and corals.
Strata The name given to the formation of layers of rock by the deposition of sediment. Over many millions of years these layers are compressed to form tightly pack bands, evident in many areas of the world.
Statigraphy The study of rock strata.
Stegosaurs The name given to a group of dinosaurs that lived during the Jurassic and Cretaceous periods. These dinosaurs are characterised by their bony plates which ran across their back and along their tail.
Supercontinent The joining together of land masses to form a larger continent, such as Gondwana or Pangea.
Tertiary The period of time stretching between 65 to 1.8 million years ago. The period followed the episode of mass extinction and the end of the Cretaceous period.
Trace Fossil Evidence of former life preserved as a mark on a rock. A good example would be dinosaur footprints.
Triassic A period of time stretching from 248 to 206 million years ago. During this time the first dinosaurs began to evolve, which later dominated the earth during the Jurassic and Cretaceous periods.
Trilobites A former group of marine arthropods which were characterised by a hard exoskeleton and threefold division of the body. (Adapted from 'The Atlas of the Prehistoric World', Douglas Palmer.)
Tyrannosaurs The name given to a group of land dwelling predatory dinosaurs that lived during the Cretaceous period.
Vendian A period of time stretching from 600 to 545 million years ago.
Vertebrates The collective name given to animals which consist of a bony skeleton, including a backbone and paired limbs.
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