|
Home
Fossils
Explanation of Fossil Types
|
|
You can find fossils of many different shapes and sizes. Every species has its own dubble Latin name. Here you find an explanation of the names of the most abundant fossils:
|
Amber
Amber is fossil resin from trees. Sometimes perfectly preserved insects or plant remains are found within pieces of amber. Amber is very lightweight. When you tap it against your teeth, it sounds like a piece of plastic. Amber has mostly a yellowish color.
Most amber is found in the Baltic Sea region. The Russion Kaliningrad produces 90% of the worlds annual production. Pieces of amber sometimes wash ashore in The Netherlands, Germany, and the Baltic Sea region. In Madagascar also much amber is found.

A piece of amber from Groningen, The Netherlands. |
Ammonites
An ammonite is an extinct inkfish-like animal with chambers in its shell. The order of Ammonidea belongs to the class of inkfish like animals (Cephalopoda) and the phylum Mollusca. The name comes from the Egyptian god Ammon. Ammonites look like the curled rams horns which depicted Ammon.
The shell was made of aragonite, and mostly the shell itself is not fossilized. Small ammonites occasionally are completely made of pyrite. Ammonites were free swimming animals in the oceans. They could regulate there depth by pumping nitrogen gas in the old chambers of its shell. The chambers are connected with a "sipho" in which the gas was transported from the body fluids.
The size of ammonites varies between less than a centimetre to 2.5 metres diameter! Many species of ammonites existed. Most ammonites were winded, but also unwinded ammonites occurred.
The chambers of the ammonite are separated by complex "suture lines". Ammonites first occur in upper Silurian period. They became extinct at the end of the Cretaceous period. The only living family member is the nautilus .
Ammonites have evolved quickly in the course of history. Together with the fact that they fossilize very well, makes them perfect guide fossils. The stratigraphy of the Mesozoic is largely bases on the occurrence of certain species of ammonites. Especially in the Jurassic and Cretaceous periods the ammonites were abundant.

Example of an Ammonite.

Description of the suturelines occurring in goniatites, ceratites and ammonites.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Ammonites. |
Belemnites
A belemnite is the internal skeleton of a squid-like animal. Belemnites belong to the class of Inkfish like animals (Cephalopods) en the phylum of Mollusca.
The skeleton is always pointed. Belemnites mostly occur in the Cretaceous period.

Example of a Belemnite.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Belemnites. |
Bivalves
The class of Bivalves belongs to the phylum of Mollusca. The shells have two asymmetrical valves. The two valves are each others reflection (left and right valve).
Some bivalves consisted of aragonite, which does not fossilize very well. Often only the imprint is preserved. Other bivalves consisting of calcite mostly are well preserved. Bivalves are very common fossils.

Example of a bivalve. The shell itself is not symmetrical.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Bivalves. |
Brachiopods
Shell where the valve is symmetrical in itself. The two valves are not symmetrical to each other. This animal lived connected to the sea floor, filtering foodparticles from the seawater. They occur in sediments since the Cambrian period until recent. They where most numerous in the Paleozoic.

Example of the brachiopod. The shell itself is symmetrical, but the two valves of the shell are not symmetrical.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Brachiopods. |
Bryozoans
Also called "moss animals". Small colony building animals with a calcite skeleton. In every chamber there is a separate animal with tentacles to filter food from the seawater. The colonies can be shaped as a branch, fan or crust.
They occur in sediments from the Ordovician period until recent. Most colonies are rather small. Most species live in the oceans, but there are also several freshwater species.

Example of a bryozoan.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Bryozoans. |
Bulla
A bulla is the hearingbone of a sea mammal. Dolphins and whales have these bones. The bones have an irregular shape and can be up to 10 centimetres (whales). The bones are sometimes found in deposits from the Neogene and Paleogene periods.

Example of a whale bulla. |
Burrows
In sediment sometimes tracks, signs of digging or other proof of animal presence are found. They are called Ichnofossils. Often animals on the seafloor left marks in the sediments or dug holes in the mud. Burrows often can still be seen in the sediments, because the sediment which filled the irregularity have a different texture.
From many types of ichnofossils the maker is unknown. The oldest known ichnofossils are from the Precambrian period, 1.1 billion years old!
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Ichnofossils. |
Ceratites
A ceratite as an ammonite like animal with a wobbled surface. The "suture lines" are less complex. The order of Ceratida belongs to the class of inkfish like animals (Cephalopoda) and the phylum Mollusca. They occur in sediments from the Permian period until the Triassic period.
See also Goniatites and Ammonites .

Example of a Ceratite from Lügde, Germany. Photo Taco Geertsema.

Description of the suturelines occurring in goniatites, ceratites and ammonites. |
Coprolite
Coprolites are fossilized faeces of animals. Coprolites from Dinosaurs and mammals are have been found. The coprolites mostly occur in terrestrial deposits. Sometimes coprolites from marine animals, like sharks, are found. The coprolites itself can learn us about the diet of the animal. Using pollen, sometimes the paleoclimate can be determined.
The largest coprolite until now has been found in Canada. The coprolite was 7 kilograms and was from a Tyrannosaurus rex. Coprolites are not very uncommon, but difficult to recognize. |
Corals
Corals (class Anthozoa) belong to the phylum Cnidaria. Corals are colonies of polyp like animals, living mainly in tropical oceans. By asexual reproduction colonies can grow from one coral cell. Corals build reefs because of the calcareous skeletons. In cooler waters corals also occur, but they do not built reefs there.
The coral phylum can be subdivided in Rugosa, Tabulata and Scleractinia corals. Tabulate corals are always colonies, but Rugose corals are often solitary. All corals have calcareous skeletons.
Rugosa and Tabulata occur in sediment from the Ordovician period until extinction at the end of the Permian period. Scleractine corals developed in the middle Triassic period and at present they are the most important builders of reefs in the world. Their skeleton consists of fast soluble Aragonite. Commonly only prints of these fossils are found. In the fossils you can often perfectly recognize the separate chambers of the coral cells.

Example of a Rugose coral.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Corals. |
Crinoids
Crinoids belong to the Phylum (Echinodermata). Like all echinoderms the have a radial symmetry of five. Mostly only small parts of stems are found. Crinoids are also called sea lilies. At present they are very rare in shallow waters, but in the paleozoic they where as common as other "echinoderms" like starfishes and sea urchins . Crinoids lived normally on the seafloor where they used there heads to filter food particles from the water. The more recent forms are free swimming, and not attached to the seafloor.
They occur in sediments from the Ordovician period until recent. In Paleozoic sediments they are very abundant.
Mostly only the stems are found. The heads are quite rare. The stems fall apart in slices after the death of the animal. Sometimes thick deposits were formed with crinoid parts.

Examples of crinoid stems.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Crinoids. |
Cystoidea
This group of animals belong to the phylum of "echinodermata", like the sea urchins. They are spherical and were connected with a stem to the seafloor. They first occur in sediments from the Ordovician period. In the Devonian period they vanished.

Example of cystoidea. |
Fishes
Fishes belong to the group of Vertebrates. The oldest known fish fossils are known from the lower Cambrian period. The first fishes belong to the group of jawless fishes (Agnatha). At the beginning of the Silurian period, the first jaw-fishes occurred (Chondrichthyes).
In the Devonian the first armoured fishes (Placodermi) with armoured plates at the outside appeared. Also the bone-fishes appeared. The group of bone-fishes includes most of todays fishes. Teeth, armoured plates, and vertabrea are frequently found as fossils.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Fishes. |
Foraminifers
Foraminifers are chambered single cell organism with a chalk skeleton. The subphylum Foraminifera belongs to the empire of Prostista. The popular name for foraminifers is forams.
There are large foraminifers, which can be seen with the naked eye, and small foraminifers. The large foraminifers live on the bottom of the sea, and the small ones are planctonic. The chambers are distributed like a spiral and connected through pores. The pores and the size is different than in ammonites , although the shape is similar.
Foraminifers are used in geological research to reconstruct the environment and climate in past geologic periods. The foraminifers occur in sediments from the Cambrian period until recent. Because of their fast evolution, many foraminifers are used as guide fossils .

Example of a Large foraminifer from the Spanish Pyrenees.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Foraminifers. |
Gastropods
Gastropod is the scientific name for snail. The gastropods belong to the phylum of Mulusca. Gastropods first occurred in the Cambrian period. They live on land as well as in the oceans. Gastropods living in the oceans are often predators. They bore holes in other shells to eat them.
Gastropods are mostly made of the mineral Aragonite. This mineral is soluble in water, and the shell in often not preserved as a fossil. The filling of the gastropod is often found as a print of the inside of the original shell. Fossils of gastropods are very common.

Example of a gastropod.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Gastropod. |
Genus
The scientific classification of organisms is based on the difference between groups of organisms on the basis of characteristics. For example: humans are named Homo sapiens. Homo is the genus and sapiens is the species name. |
Goniatites
Small ammonite like animals from the Devonian and Carboniferous periods. The "sutures" are simple because the "septa" are little folded. The order of Goniatitida belongs to the class of Inkfish like animals (Cephalopoda) and the phylum of Mollusca.

Description of the suturelines occurring in goniatites, ceratites and ammonites. |
Graptolites
Graptolietes are part of the phylum Hemichordata. Graptolites occur is sediments from the middle Cambrian to the beginning of the Carboniferous period. Many graptolites were planktonic and floated in the upper part of the ocean waters. There external skeleton was made of organic material (chitine) and not of chalk. Graptolites formed colonies by asexual reproduction.
When they died, the skeletons sunk to the bottom en were preserved in laminated clays under anoxic conditions. Because of the anaerobic (without oxygen) environment the organic material was preserved. Graptolites were flattened in the black shales, and look like jigsaws in many varieties.
Graptolites occur in great numbers in deep sea sediments from the Ordovician and Silurian periods. In these periods graptolites are used as guide fossils.
Example of the graptolite Monograptus from Bornholm, Denmark.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Graptolites. |
Guide fossils
Guide fossils are characteristic of a certain layer in the stratigraphy. Suitable fossils have a limited distribution in time, occur in a large geographical area, and must be common. The best guide fossils evolved very quickly, and cover a limited time span in the stratigraphy. Using known guidefossils, it is easy to date a certain layer. For a more precise result, it is necessary to combine several dating methods. |
Ichnofossils
Ichnofossils are fossil prints left by living organisms. Tracks, footprints, burrows, and other marks are examples. From many types of ichnofossils the maker is unknown.

Example of a footprint of a saurian from Winterswijk, The Netherlands.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Ichnofossils. |
Mammals
Fossil mammals belong to the group of Vertebrates. Land animals from mouse to elephant are part of this group, but also sea mammals like whales. The oldest mammals are known from the Triassic period. After the extinction of the dinosaurs at the end of the Cretaceous period, the mammals could evolve quickly.
The first sea mammals are known from the Eocene (part of the Paleogene period). Very famous mammals are the whooly mammoth from the ice age deposits from the Pleistocene. |
Mammoth
Mammoths are the most famous extinct animals from the Pleistocene. In Europe many fossil mammal fossils are fished from the bottom of the North sea (Doggersbank, Brown bank). The bones are also found in the large rivers in The Netherlands. Many Dutch museum depots are completely filled with mammoth bones.
Many species of mammoth coexisted at the same time. The best known mammoth is the Whooly Mammoth (Mammuthus primigenius). In Europe also plain mammoth (Mammuthus trogontherii), and the Southern mammoth (Mammuthus meridionalis) occurred. The dwarf mammoth (Mammuthus lamarmorae) occurred on the islands in the Mediterranean. From North America the Emperor Mammoth (Mammuthus imperator) and the American Mammoth (Mammuthus columbi) are known.
The mammoths are known from the Pleistocene (part of the Neogene period). The whooly mammoth and plain mammoth had a thick fur and long hairs. The other mammoths had less or no hair, because they liver in warmer areas. The American mammoth was very large. The European mammoths had roughly the size of todays elephants. The European mammoth had long tusks.
Mammoths were large grazers, and ate grass. The mammoth became extinct at the end of the last ice age, approximately 10.000 years ago. Several small populations became extinct much later. There is a discussion going about if humans are responsible for the extinction of mammoths.
In Siberia, complete frozen mammoths have been found in the permafrost tundra. This led to new discoveries about the diet of mammoths. Hairs and stomach content was examined.

Example of a mammoth tooth. Photo: Olof Moleman |
Mosasaur
The first Mosasaurus was found in 1766 in the St. Pietersberg hill in Maastricht, The Netherlands. This is how the animal got its name. The first find can stil be seen in the Teylers Museum in Haarlem, The Netherlands. During the Maastrichtian (part of the Cretaceous period) the Mosasaur was one of the large marine predators.
The reptile was long, slim and had four flippers. There are several species known from several locations over the world. The size varies, the largest known mosasaurs could grow up to 10 metres long. Mosasaurs became extinct at the end of the Cretaceous period.
In the limestone in the south of the Netherlands mosasaur remains are quite common. Loose teeth are most common, several bones together are rare.
In 1998 a partial skeleton of a Mosasaurus was discovered. The animal was scavenged by sharks after its death. Because of this, not the complete skeleton was found. De mosasaur was named Bčr, and can be seen in the Natural History Museum in Maastricht, The Netherlands. Bčr has been described as a new species: Prognathodon saturator. |
Nautilus
The order of Nautilida belongs to the class of inkfish like animals (Cephalopoda) and the phylum Mollusca. The nautilus is an inkfish like animal. The "sipho" (tube which connect the chambers) is centered in the middle of the chambers. The animal can go up and down in the water column by regulating the amount of water in the chambers.
The "suture lines" are less developed than in ammonites . They occur in sediments from the end of the Cambrian period until recent. The nautilus still lives in the ocean waters near Madagascar.

Example of a recent Nautilus.

Example of a fossil Nautilus.

Description of the suturelines occurring in goniatites, ceratites and ammonites. |
Orthoceras
An Orthoceras in an elongated inkfish like animal. The different chambers can be observed in the fossils. Orthoceras belongs to the group of Cephalopods.
Example of a orthoceras.
Click here for information where to find Cephalopods.
Go to the Photo page to view photographs of Cephalopods. |
Ostracods
The order of the Ostracoda belongs to the class Crustacea (crayfish like animals) and the phylum Arthropoda. Ostracods live on the seafloor and also in freshwater.
The "shell" of this animal is often well preserved and consists of two halves. The size of the shell is commonly only a few millimetres, but some species can grow to a size up to a few centimetres.

Example of an ostracod from Gotland, Sweden.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Ostracods. |
Otoliths
Otoliths are hearing stones of fishes. These are in the balance organ to determine the position of the fish in the water column. The small bones consist of several thin chalk layers. Normally these are smaller than one centimetre. These fossils are common in Neogene and Paleogene deposits.

Example of an Otolith from Mill. |
Plants
The study of plants is also called Paleobotany. Life on land occurred much later than life in the oceans. On land the first organisms were lichens and algae. The first plants occurred in the lower Silurian period. In the middle Devonian fern trees and the first forests occurred. In the upper Devonian the first seedplants like seed ferns and fern palms originated.
In the Carboniferous period there was lush plant growth. The thick coal layers from this period are a worldwide witness to this. In swamps thick layers of peat formed. Due to compression the coal was formed. In the Carboniferous many new plant groups evoluated. Conifers first occurred at the end of the Carboniferous. Famous fossils from the Carboniferous period are Calamites, Neuropteris, and Lepidodendron.
Flowering plants first occurred in the lower Cretaceous period. Deciduous trees and palms evaluated. Flowering plants still dominate the plant kingdom. |
Ray teeth
Rays, together with sharks form the class of cartilage fishes (Chondrichthyes).
Ray teeth, like shark teeth, become black when fossilized. Ray teeth are recognized because of the rectangular shape with small ridges. Rays have a cartilage skeleton.

Example of a ray teeth from Cadzand, The Netherlands.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Ray teeth. |
Rudists
Strange group of animals belonging to the group of the bivalves. Rudists are extinct.

Example of a rudist.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Rudists. |
Scaphopods
Scaphopods are also knows as elephant teeth. It has nothing to do with elephants, but it is a wormlike animal. The Dentalium belongs to the group of Scaphopods. The Scaphopods are part of the phylum Mollusca.
Inside the curved hollow shell lived a worm-like animal. The animal was dug in in de seabottom. The thin end was positioned upwards, and the animal filtered small food particles from the water. Scaphopods are known from sediments from the upper Cambrian period until recent.

Example of a Scaphopod. |
Sea urchins
Sea urching belong to the phylum of Echinodermata. Just like other echinoderms they have a radial symmetry of five. The shell consists of grown together chalk elements. The spines could move, and were attaches to the chalk elements. Sea urchins live on the seafloor.
The shell of sea urchins often in well preserved. The shell is made of calcite. The spines usually fall of and are found separately. Sea urchins first occurred in the Ordovician period.

Example of a Sea urchin.
There are two types of sea urchins. The regular sea urchins are totally five radial symmetrical. Their anus is on top, and their mouth is on the bottom. Irregular sea urchins have their mouth and anus both on the bottom. There sea urchins are less symmetrical.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Sea urchins. |
Serpulids
Serpulids are a kind of wormlike creatures with a chalk tube. The family Serpulidae belong to the phylum Annelida. Serpulids occur from the Silurian period, and from the Jurassic period became more common.
The fossils known from this group are a kind of chalk tubes. These are knows straight as well as winded. The difference between gastropods (snails) is that serpulids are irregular on the outside, but perfectly round on the inside. Gastropods are different.

Example of serpulids.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Serpulids. |
Shark teeth
Together with Ray fish, the sharks form the class of Chondrichthyes.
Shark teeth adopt the colour of the sediment in which it is buried. Often they turn black or grey when fossilized. They are solid, consist of calcium phosphates, and do fossilize very well. Sharks have rotating jaws in which new teeth are created permanently. It is estimated that a single shark looses up to 10.000 teeth in its lifespan. Sharkteeth are numerous in sediments from the Cretaceous and Paleogene periods.
From the cartilage skeleton, sometimes vertebrae are found.. Heterodonts produce several types of teeth depending on the place in the jaw. One species of Heterodont always has more types of teeth. Homodonts have only one type of teeth.

Example of a shark teeth from Antwerp, Belgium.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Shark teeth. |
Species
The scientific classification of organisms is based on the difference between groups of organisms on the basis of characteristics. For example: humans are named Homo sapiens. Homo is the genus and sapiens is the species name. |
Sponges
Sponges belong to the phylum Porifera. Sponges are primitive multicellular animals, living attached to the seafloor. They filter the seawater to extract foodparticles. In some sponges you can sea the wastewater opening where the filtered water was discharched.
Most sponges have a skeleton that consists of small skeletal parts (specula) made of spongine, chalk or silica. The taxonomy of the sponges is based on the type of skeleton: Spongine sponges (Demospongiae), Chalksponges (Calcispongiae) and silica sponges (Hexactinellida). Sponges with a silica skeleton fossilize easily. Especially in Cretaceous deposits, sponges are abundant. The oldest known sponges are from the Precambrian period.

Example of a sponge from Paulmy, France.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Sponges. |
Stromatolites
Stromatolites are laminated layers of small chalk particles glued together by mats of blue algae (Cyanobacteria). The primitive Cyanobacteria did not have a cell nucleus, and only has chlorophyll.
These fossils are among signs of the oldest lifeforms on earth. Specimens have been found in sediments from the middle Proterozoic (1.8 billion years old). In the Proterozoic thick layers of limestone was formed by the stromatolites. Stromatolites still occur on a few locations on Earth.

Example of a stromatolite. |
Stromatopores
Stromatopores were marine organisms with a chalk skeleton. In the Silurian and Devonian periods, stromatopores were important reef builders. Stromatopores form a patern of characteristic laminated chalk layers. At the end of the Devonian period they became extinct.
The taxonomy of this group is unclear. Mostly the are classified with the sponges (phylum Porifera). Sometimes flow openings can be seen, similar to the sponges. In stromatopores these flow openings are called astorhidzen.

Example of a Stromatopore with astorhidzen. |
Trilobites
Trilobites belong to the group of Arthropods. Trilobites are the oldest known animals with eyes. They occur in sediments from the Cambrian period and became extinct at the end of the Permian period in the Paleozoic . The name is because of the three lob configuration of the skeleton. They have two pleural lobes, and one axial lobe in the middle. Three parts can be distinguished in trilobites: the cephalon (head), the thorax (body) and pygidium (tail).
The armour of trilobites was made of Chitin. Because of the hard armour, trilobites had to shed their skin regularly. That is why separate heads and tail parts are found.

Elrathia kingii, middle-Cambrian, Wheeler formation, Utah USA. Photo: © Tomas Hekkers
Some trilobites on or close to the seafloor. They lived of plankton, and other small organisms. The size varies between several millimetres up to 72 centimetres (New Foundland, Isotelus rex). New (sub)species are still found. The shape of trilobites can vary. There were species with or without spines, blind species, or trilobites with large eyes. Trilobites have facet eyes, which have sometimes been beautifully preserved in the fossils.
Whole trilobites can be found as fossil, but also the separate parts of the skeleton, or the walking tracks of trilobites (cruziana). The tracks are footprints, and the tracks where the animals dug into the bottom. Only the skeletal parts of the trilobites have been preserved.

Example of a trilobite track (Cruziana).
Trilobites can be found in many countries. The main areas known for its trilobites are the Chech Republic, Morocco, and the USA. In Europe you can also find trilobites in the UK, Germany, Sweden, Estonia, and Belgium.
In the phylum Arthropoda the class of Trilobita can be subdivided into nine orders. The Phacopida are best known, with the species Phacops. The nine orders are subdivided in 150 families, with in total more than 15000 described species.
Click here for information where to find these fossils.
Go to the Photo page to view photographs of Trilobites. |
Cenozoic
The Cenozoic is the Neogene and Paleogene together. |
Mesozoic
The Mesozoic is the Cretaceous , Jurassic and Triassic together. |
Paleozoic
The Paleozoic is the Permian , Carboniferous , Devonian , Silurian , Ordovician and Cambrian together. |
Quarternary
This (old) period is now part of the Neogene period. |
Tertiary
This (old) period has been split up in the Neogene period and the Paleogene period. |
Neogene
Period since 23 million years until present.
The primates and humanoids developed in the Neogene.
Period
| Epoch
| Stage
| Age (in Milion years) * |  | Holocene
| 0 - 0,0115
| Pleistocene
| Weichselian
| 0,0115 - 0,11
| Eemian
| 0,11 - 0,15
| Saalian
| 0,15 - 0,38
| Holsteinian
| 0,38 - 0,40
| Elsterian
| 0,40 - 0,42
| Cromerian
| 0,42 - 0,85
| Bavelian
| 0,85 - 1,07
| Menapian
| 1,07 - 1,20
| Waalian
| 1,20 - 1,45
| Eburonian
| 1,45 - 1,81
| Pliocene
| Gelasian
| 1,81 - 2,59
| Piacenzian
| 2,59 - 3,60
| Zanclian
| 3,60 - 5,33
| Miocene
| Messinian
| 5,33 - 7,25
| Tortonian
| 7,25 - 11,61
| Serravallian
| 11,61 - 13,65
| Langhian
| 13,65 - 15,97
| Burdigalian
| 15,97 - 20,43
| Aquitanian
| 20,43 - 23,03
| * Age is rounded
Click here for locations from this period.
Go to the Photo page to view photographs of fossils from the Neogene. |
Paleogene
Period ranging from 66 million years ago until 23 million years ago.
In this period fast development of mammals and birds occurred.
Period
| Epoch
| Stage
| Age (in Milion years) *
| 
| Oligocene
| Chattian
| 23,0 - 28,4
| Rupelian
| 28,4 - 33,9
| Eocene
| Priabonian
| 33,9 - 37,2
| Bartonian
| 37,2 - 40,4
| Lutenian
| 40,4 - 48,6
| Ypresian
| 48,6 - 55,8
| Paleocene
| Thanetian
| 55,8 - 58,7
| Selandian
| 58,7 - 61,7
| Danian
| 61,7 - 65,5 | * Age is rounded
Click here for locations from this period.
Go to the Photo page to view photographs of fossils from the Paleogene. |
Cretaceous
Period ranging from 145 million years ago until 66 million years ago.
The dinosaurs became extinct at the end of the Cretaceous period almost certainly because of a large meteorite impact. Ammonites were flourishing during the Cretaceous, but they also became extinct. Mammals and flowering plants began developing.
| Period | Epoch
| Stage
| Age (in Milion years) *
|
| Upper
| Maastrichtian
| 65,5 - 70,6
| Campanian
| 70,6 - 83,5
| Santonian
| 83,5 - 85,8
| Caniacian
| 85,8 - 89,3
| Turonian
| 89,3 - 93,5
| Cenomanian
| 93,5 - 99,6
| Lower
| Albian
| 99,6 - 112,0
| Aptian
| 112,0 - 125,0
| Barremian
| 125,0 - 130,0
| Hauterivian
| 130,0 - 136,4
| Valanginian
| 136,4 - 140,2
| Berriasian
| 140,2 - 145,5 | * Age is rounded
Click here for locations from this period.
Go to the Photo page to view photographs of fossils from the Cretaceous. |
Jurassic
Period ranging from 200 million years ago until 146 million years ago.
This is the time of the large reptiles. Many species of dinosaurs developed. Also flying dinosaurs, like the Archaeopteryx developed. These flying dinosaurs developed later into birds. The number of mammal species and crustaceans increased, and the first crocodiles appeared. The plants developed further. Many ammonites en sea urchins .
Period
| Epoch
| Stage
| Age (in Milion years) *
|
| Upper (Malm)
| Tithonian
| 146 - 151
| Kimmeridgian
| 151 - 155
| Oxfordian
| 155 - 161
| Middle (Dogger)
| Callovian
| 161 - 165
| Bathonian
| 165 - 168
| Bajocian
| 168 - 172
| Aalenian
| 172 - 176
| Lower (Lias)
| Toarcian
| 176 - 183
| Pliensbachian
| 183 - 190
| Sinemurian
| 190 - 197
| Hettangian
| 197 - 200
| * Age is rounded
Click here for locations from this period.
Go to the Photo page to view photographs of fossils from the Jurassic. |
Triassic
Period ranging from 251 million years ago until 200 million years ago.
Beginning of the development of dinosaurs. First mammals and new species of plants appeared. This was the flourishing period of ferns. Fossils of turtles have been found.
Period
| Epoch
| Stage
| Age (in Milion years) *
|
| Upper (Keuper)
| Rhaetian
| 200 - 204
| Norian
| 204 - 217
| Carnian
| 217 - 228
| Middle (Muschelkalk)
| Ladinian
| 228 - 237
| Anisian
| 237 - 245
| Lower (Buntsandstein)
| Olenekian
| 245 - 250
| Indian
| 250 - 251
| * Age is rounded
Click here for locations from this period.
Go to the Photo page to view photographs of fossils from the Triassic. |
Permian
Period ranging from 299 million years ago until 251 million years ago.
The final period of the Paleozoic. Further development of reptiles and many molusks. First Ginkgo trees developed. The number of amphibians and insects decreased. The primitive armoured fishes became extinct. Flourishing period of the Trilobites . At the end of the Permian there was an mass-extinction. The cause is still unclear.
Period
| Epoch
| Stage
| Age (in Milion years) *
| 
| Lopingian
| Changsingian
| 251 - 254
| Wuchiapingian
| 254 - 260
| Guadalupian
| Capitanian
| 260 - 266
| Wordian
| 266 - 268
| Roadian
| 268 - 271
| Cisuralian
| Kungurian
| 271 - 276
| Artinskian
| 276 - 284
| Sakmarian
| 284 - 295
| Asselian
| 295 - 299
| * Age is rounded
Click here for locations from this period.
Go to the Photo page to view photographs of fossils from the Permian. |
Carboniferous
Period ranging from 359 million years ago until 299 million years ago.
First reptiles. Further development of flying insects, amphibians and plants. First sigularia trees. Extinction of the graptolites .
Period
| Epoch
| Stage
| Age (in Milion years) *
|
| Upper
| Gzelian
| 299 - 304
| Kasimovian
| 304 - 307
| Moscovian
| 307 - 312
| Bashkirian
| 312 - 318
| Lower
| Serpukhovian
| 318 - 326
| Vesean
| 326 - 345
| Tournaisian
| 345 - 359
| * Age is rounded
Click here for locations from this period.
Go to the Photo page to view photographs of fossils from the Carboniferous. |
Devonian
Period ranging from 416 million years ago until 359 million years ago.
First sharks, amphibians, ammonites , and insects. The diverse group of crustaceans probably first left the water. Fishes left the water too. Large number of species of invertebrates and fishes. Development of plant leaves.
Period
| Epoch
| Stage
| Age (in Milion years) *
|
| Upper
| Famennian
| 359,2 - 374,5
| Frasnian
| 374,5 - 385,3
| Middle
| Givetian
| 385,3 - 391,8
| Eifelian
| 391,8 - 397,5
| Lower
| Emsian
| 397,5 - 407,0
| Pragian
| 407,0 - 411,2
| Lochkovian
| 411,2 - 416,0
| * Age is rounded
Click here for locations from this period.
Go to the Photo page to view photographs of fossils from the Devonian. |
Silurian
Period ranging from 444 million years ago until 416 million years ago.
Many mollusks, gastropods , bryozoa , brachiopods and jawless fishes roamed the earth. First land plants and land animals.
Period
| Epoch
| Stage
| Age (in Milion years) *
|
| Pridoli
| 416 - 419
| Ludlow
| Ludfordian
| 419 - 421
| Gorstian
| 421 - 423
| Wenlock
| Homerian
| 423 - 426
| Sheinwoodian
| 426 - 428
| Llandovery
| Telychian
| 428 - 436
| Aeronian
| 436 - 439
| Rhuddanian
| 439 - 444
| * Age is rounded
Click here for locations from this period.
Go to the Photo page to view photographs of fossils from the Silurian. |
Ordovician
Period ranging from 488 million years ago until 444 million years ago.
In the Ordovician period there were many trilobites and graptolites . Several mollusks developed. The number of species of primitive fishes and (sea)plants increased. Brown, red and green algae developed. First fishes with a developed skeleton and muscles. At the end of the Ordovician period there is a mass extinction.
Period
| Epoch
| Stage
| Age (in Milion years) *
|
| Upper
| Hirnantian
| 444 - 446
|
| 446 - 456
|
| 456 - 461
| Middle
| Darriwilian
| 461 - 468
|
| 468 - 472
| Lower
|
| 472 - 479
| Tremadocian
| 479 - 488
| * Age is rounded
Click here for locations from this period.
Go to the Photo page to view photographs of fossils from the Ordovician. |
Cambrian
Period ranging from 542 million years ago until 488 million years ago.
Cambrian explosion of life. Development of algae and animals with armor. In this period there were many species of trilobites , jellyfish, sponges , graptolites , echinoderms, brachiopods en inkfish. First primitive vertebrates, primitive fishes and (sea)plants (psilophytes).
Period
| Epoch
| Stage
| Age (in Milion years) *
|
| Upper (Furongian)
|
| 488 - 501
| Paibian
| Middle
|
| 501 - 513
|
| Lower
|
| 513 - 542
| | | * Age is rounded
Click here for locations from this period.
Go to the Photo page to view photographs of fossils from the Cambrian. |
Precambrian
The Precambrian consists of several parts. The name Precambrian is not an "eon"anymore is the most recent stratigraphic charts. In the Archaeďc (3800 to 2500) fossils ara found from cyanobacteria in sea deposits.; stromatolites . From the lower and middle Proterozoďc (2500 to 1000) colony forming bacteria (without nucleus) are known followed by Eucariotic bacteria (with nucleus). From the upper Proterozoďc (1000 to 542) the first colony forming animals are known like sponges.
| Eon:
| Era:
| Period:
| Age (in Milion years) *
| 
| Proterozoic
| Neoproterozoic
| Ediacarian
| 542 - 630
| Cryogenian
| 630 - 850
| Tonian
| 850 - 1000
| Mesoproterozoic
| Stenian
| 1000 - 1200
| Ectasian
| 1200 - 1400
| Calymmian
| 1400 - 1600
| Paleoproterozoic
| Statherian
| 1600 - 1800
| Orosirian
| 1800 - 2050
| Rhyacian
| 2050 - 2300
| Siderian
| 2300 - 2500
| Archaeic
| Neoarchaeic
| 2500 - 2800
| Mesoarchaeic
| 2800 - 3200
| Paleoarchaeic
| 3200 - 3600
| Eoarchaeic
| no lower limit - 3600
| * Age is rounded |
|
The following information about fossils is available:
|