The History of Life on Earth
table below tells you how life began and changed, from Earth's beginnings to the
present. Geologists divide Earth's history into different periods, such as
the Cretaceous, when T rex lived. The tables below and on the left give dates in millions of years
- for example, the Jurassic began 200 million years ago (mya) and lasted until 145
mya. Below you can also see some of the main features and events
which took place in each period - the first dinosaurs lived in the Triassic,
230 mya, and the first cat evolved in the
Oligocene, 30 mya.
These periods are mainly defined by
the kind of animals and plants which lived at these times. At the end of
most periods there were mass extinctions. The most catastrophic of these was
at the end of the Permian, when a huge number of species died out - 96% of
invertebrates, 66% of vertebrates, and 50% of plants. At the end of the
Cretaceous there was another major extinction event which killed off the
dinosaurs and many other living things, such as ammonites.
on the right gives the dates of some of the animals and plants which appear in the
Fossils and Bones workshop, either as fossils or as
the skeletons which the
children make. Species names are given in bold italics, e.g.
A NOTE ABOUT EVOLUTION
In the table you will
se a lot of firsts - the first dinosaur, the first mammal, etc. But bear in
mind that evolution is a very gradual process, and often there is no clear
dividing line between an animal that is one type versus another. Scientists
often argue about such things - for example, what exactly is a mammal, or a
bird? There is a far smaller difference between say Archaeopteryx, the first
bird, and the dinosaurs it evolved from, than there is between Archaeopteryx
and a modern bird like a parrot or hawk. And the so-called first of a type
of animal, such as the first whale, may look very little like a modern whale
- it just has certain features (e.g. the shape of the skull) which tell us
that all whales are descended from it.
In the Miocene, around 6
mya, creatures evolved from apes which eventually developed
into human beings. All the 'hominin' species we know of are given in the
table, in the right hand column so they can be seen more clearly, with the dates they lived (e.g. Homo habilis, 2.2-1.6
million years ago), as well as the size of their brains (where known - given
in cubic centimetres, or ccm). As you will see,
brain sizes increase through time, with our own species, Homo sapiens,
having the largest brains.
To see pictures showing life in each
period, click on the name of each period, below or in the table to the left (COMING SOON).
There is a great deal of
information in this table, so you may want to dip in and out!
Main features and events
Animals and plants featured in the workshop
Earth forms from dust and gas
around the sun.
bombarded by comets and asteroids and is a hot, lifeless place of molten
End of bombardment by asteroids. Continents of solid
rock form, and then oceans. The atmosphere contains mainly nitrogen, methane
and carbon dioxide. There is no oxygen.
About 3.8 billion years ago, life begins in the oceans:
things called archaea, similar to bacteria. They do not need oxygen and live off
energy stored in the rocks and minerals of the earth - chemicals such as sulphides.
They are made up of just one cell- a very small sack of
liquid, chemicals, little organs that produce energy, and DNA - the
instructions for building the cell itself. It will be 3 billion years
before living things have more than one cell (we have trillions in our own bodies).
Cyanobacteria evolve - also known as
blue-green algae. These are the first living things to photosynthesise, like
plants. They take carbon dioxide from the air and water to make energy, and
give off oxygen. Over the next few hundred million years
the atmosphere fills with oxygen, and this allows new forms of life to evolve. Cells
very slowly become more complex.
1850 - the first organism with cells containing a
1500 - first complex cell, possibly a fungus.
1200 - first organisms on land.
713-635 - first evidence for multi-celled animals,
565 - Ediacaran animals - found in
Ediacara Hills in Australia and other countries. Include Charnia, a
creature shaped like a feather, first found near Leicester, and other
soft-bodied creatures similar to jellyfish and sea pens.
550 - first anthozoans (corals and sea anemones) and
Enormous increase in animal diversity, known as the
'Cambrian explosion'. Many new types of marine animals evolve,
many of which are still alive today.
540 - small shelly creatures.
535 - first trilobites (creatures like
big woodlice, with bodies divided into three lobes), many other types of
arthropods (creatures with bodies divided into segments, like modern insects
and centipedes), first crustaceans (modern species include crabs, lobsters, shrimps),
molluscs (like modern snails and squids), echinoderms (like modern starfish,
crinoids, sea urchins), and many more types of animals.
530 - first chordates (fish-like creatures, with a cord
along their backs which evolved into a backbone) - e.g. Pikaia -
similar to a modern lancelet.
530 - first vertebrates - tiny fish
with no jaws, e.g. Myllokunmingia and
510 - first cephalopods (like modern nautilus, which
looks like a squid in a spiral shell)
505 - creatures found in the famous Burgess
Shale in Canada - strange looking animals like Marrella,
Anomalocaris and Wiwaxia.
500 - first evidence of arthropods on land (fossils
showing movements in the mud)
540 - Conocoryphe sulzeri -
Huge increase in diversity of marine life - the number of
species triples. Trilobites flourish.
485 - first vertebrates with bone -
jawless fishes, e.g. Arandaspis (appeared 470). The first bony
plates, scales, and possibly teeth develop.
480 - first starfish and crinoids
475 - first plants (spores of very
450 - first burrows created by land animals
445 - mass extinction - half of all
species die, mainly trilobites and echinoderms.
440 - First spores of complex plants
440 - new species of jawless fish
430 - first fish like sharks ('protosharks'), first fish
425 - first land plant, Cooksonia
420 - first arachnid (spider family), first land
scorpion, first ray-finned fish
The 'Age of Fish' - huge increase in
number of fish species. Also many new plant species, spreading across land
and creating the first forests.
410 - first true fish teeth
400 - first horsetails (a plant which still exists today)
400 - first true sharks;
first breathing of air (in lungfish)
395 - first lichen, first ammonoid (later evolved into
385 - first tree-like plants, first big forests
380 - first spiders,
first land millipedes and centipedes, first goniatites (an ammonoid)
380 - first lobe-finned fish. These later evolved legs and
375 - first amphibian (modern species
include frogs and newts), first coelocanth
365 - mass extinction - up to 70% of
360 - first ferns, first crabs
410 - Urasterella asperula -
brittle star (thin legged starfish)
400 - Hapalocrinus elegans -
crinoid, sea animal which attached to the sea floor and had a flower like
structure for feeding.
Carboniferous means 'coal-bearing', and
this was the period when huge forests grew over the earth and later turned
to coal. Many kinds of plants flourished, including ferns, horsetails, and
trees (which were not like modern trees).
350 - insects evolved wings - the first flying creatures
350 - the first large sharks
330 - the first amniote - Palaeothyris - a vertebrate which laid eggs.
An important step in
evolution, as the eggs can be laid on land, not only in water
325 - first dragonflies
320 - first conifers (trees like modern pines)
320 - giant millipedes, e.g. Arthropleura,
up to 3m long!
310 - giant dragonflies (over 60cm wingspan)
310 - first plant-eating vertebrates; first
synapsids - egg-laying animals like reptiles,
e.g. Ophiacodon. These later evolved into mammals,
305 - first diapsids, a type of reptile, e.g. Spinoaequalis.
Many animals evolved from diapsids including lizards, snakes, dinosaurs,
croocodiles, and birds.
320 - Xyloiulus sigillariae -
315 - Horsetails (also known as calamites, a plant).
Many of the fossils sold in the workshop are
Carboniferous, as there are several local Carboniferous sites for collecting
fossils, such as:
-Newhey Quarry, near Rochdale
-Poise Brook, Offerton
-Besom Hill, near Oldham
for details visit the
Many kinds of reptiles developed in the Permian. The
synapsids include Dimetrodon, a 3m long
predator with a big 'sail' on its back. Some synapsids turned into
mammal-like reptiles known as cynodonts, e.g.
Procynosuchus. They had
features that helped them to hunt - their legs were longer and placed
more directly under the body, they had different sorts of teeth like
incisors and canines, and their eyes moved forward to help them see in 3D. In the
the cynodonts evolved into mammals. However there were no dinosaurs
yet - these did not evolve until the middle of the Triassic.
290-280 - seed plants and conifers diversify (that is, the number
of species increased)
280 - Dimetrodon
280 - the first beetles
275 - ceratites (a type of ammonoid, later became
275 - pelycosaurs die out (sail-backed reptiles like
Dimetrodon and Edaphosaurus)
251 - largest mass extinction of all time - death of 50%
of plant species, 96% of invertebrates (including all trilobites), and two
thirds of amphibians, reptiles and therapsids (mammal-like reptiles). Caused
by several things: huge volcanic eruptions which poisoned the air and
starved the oceans of oxygen, global warming, and a huge lowering of sea
levels which caused massive loss of animal habitats.
The Triassic, Jurassic and
Cretaceous are known as the
Mesozoic era, or the Age of Dinosaurs. Dinosaurs evolved
from reptiles about 230 million years ago and died out at the end of the
Cretaceous, 65 million years ago, lasting 165 million years in all. They are
closely related to pterosaurs (the flying reptiles) and distantly related to
crocodiles, but neither of these are dinosaurs - nor are the sea reptiles such as
Once the climate disaster at the end of the Permian had
settled down, a lot of new important animals evolved. These include:
245 - archosaurs - a large
family of reptiles. They later evolved into crocodiles, dinosaurs and birds.
240 - goniatites die out (similar to ammonites)
Early Triassic - first ichthyosaurs,
e.g. Mixosaurus (sea reptile resembling a dolphin) - grew to about
1m, although later ichthyosaurs were enormous - Shastasaurus grew to 21m, the largest
sea reptile ever.
Euparkeria - a primitive archosaur, had some
dinosaur-like features, such as long back legs, good for running fast, and a
space in the skull in front of the eye which meant it had a good sense of
Later Triassic - Postosuchus - a large
archosaur, from a line which led to crocodiles, had a huge skull and teeth
like T rex
Mastodonsaurus - the largest amphibian ever at
6m, looked like a crocodile
230-225 - first dinosaurs -
Eoraptor, Herrerasaurus, Coelophysis - 1-3m long, they were slender and
ran on two long legs, and had sharp teeth and claws and long necks.
Dinosaurs first lived in Argentina in South America, but spread across the
whole planet, diversifying into many species.
Late Triassic - Eudimorphodon - one of
the first pterosaurs, or flying reptiles. Pterosaurs had
incredibly long fourth fingers which supported the wings, made of skin. They
were about the size of a goose (10kg), but later pterosaurs grew enormous (Quetzalcoatlus
had a 12m wingspan - as big as a small plane)
220 - the first turtle, Odontochelys
220 - first flies
220 - first prosauropods - a large
plant-eating dinosaur, e.g. Plateosaurus, which grew to 10m in length and 700kg
in weight. They had long necks and tails, and teeth adapted for chewing
leaves, like the later sauropods (e.g. Brachiosaurus)
215 - Dicynodonts (see Permian period) evolved from
mammal-like reptiles (e.g. Placerias, Lystrosaurus) into mammals -
e.g. Morganucodon, Eozostrodon. They looked like shrews (or rats),
with fur. They suckled their young with milk. All mammals
evolved from these shrew-like creatures, including us.
Gingko - a tree which evolved in the
Triassic and thrived during the Jurassic. It declined to just one species, alive today - Gingko biloba, or the maidenhair. It is used
as a herbal remedy.
The Jurassic was a time of huge
monsters on land and sea, such as Allosaurus, Brachiosaurus, and
It was also the time of the ammonites, a very successful
group of sea creatures like squids in snail shells. Ammonites are very
popular fossils which can be found on beaches all over Britain (see right).
195 - first ammonites and
belemnites (a squid-like animal - the remains of belemnites are
found in many places where ammonites are found; they look like teeth but are in fact the 'guard', a hard part of the squid's body on the
195 - first sauropods - plant-eating
dinosaurs with long necks and tails, which walked on four sturdy legs, e.g.
Vulcanodon (7m long)
190 - first modern starfish
190 - first pliosaurs (marine reptiles)
190 - first lepidoptera - family which includes moths
and butterflies - e.g. Archaeolepis
Early Jurassic - Mesolimulus - a type of
horseshoe crab. Horseshoe crabs (not true crabs) first evolved in the
Permian, but this species is very similar to the modern species,
Limulus, which lives
on the coast of North America, so it is thought of as a 'living fossil',
like the Gingko tree.
First frog - Prosalirus
Ichthyosaurus - 2m long sea reptile resembling
a dolphin, with a long thin snout full of sharp teeth for catching fish
Mammals continued to evolve, including Megazostrodon
and Sinoconodon - still resembling rats or weasels
Middle Jurassic - Liopleurodon - the top
predator in the seas of Europe, up to 10m long, with 1.5m jaws - a type of
pliosaur, with a hefty body and huge flippers.
Plesiosaurus - a typical plesiosaur (sea
reptile), up to 5m long with a very long thin neck, a small head, and four
big flippers - a very fast and powerful swimmer.
Pterosaurs - several species of these
flying reptiles evolved in the Jurassic, e.g. Dimorhpodon (1m long with big skull),
Rhamphorhynchus (2m wingspan), and
(1m wingspan; many fossils have been found, in Germany). They caught fish
with their long beaks.
Many species of dinosaur evolved,
Dilophosaurus - a 6m long
theropod - a predator which ran on two legs, with two small front legs, like
Megalosaurus - the first
dinosaur ever discovered, in 1824 in Oxfordshire, a theropod.
Mamenchisaurus - a 26m
sauropod which had the longest neck of any animal ever, up to 13m
Huayangosaurus - an early stegosaur,
4m long with two rows of plates along its back - possibly for defence, or
155 - the first bird,
Archaeopteryx - 30cm in length (crow-sized), it
had wings and a tail with long feathers, but unlike modern birds it had
claws on its wings and teeth. It evolved from dinosaurs, and some
palaeontologists think of modern birds as dinosaurs. There were many other
small feathered dinosaurs which were similar to birds, known as maniraptors.
Ten Archaeopteryx skeletons have been found; a copy of the most famous one is used in the
Fossils and Bones workshop.
Many famous dinosaurs evolved in the late Jurassic, such
Allosaurus - a huge predator, 7-12m long,
weighing up to 1.8 tonnes, which fed on large plant-eating dinosaurs
Sinraptor - a 9m theropod found in China
Compsognathus - a small theropod, only 1.3m
Brachiosaurus - a 23m sauropod
with huge legs and neck, weighing 30 tonnes. It could reach up 15m into the
trees to eat leaves. Its humerus (upper arm bone) was up to 2m long.
Diplodocus - 25-30m long, another sauropod, one
of the longest dinosaurs ever with an incredibly long neck and tail and a
small head. It grabbed branches in its jaws and used its peg-like teeth to
strip the leaves off. Its tail had up to 80 vertebrae.
Apatosaurus - once known as
another sauropod, 23m long. Weighed as much as four elephants.
Camarasaurus - the most common sauropod in
North America, 18m long.
Stegosaurus - 9m plant-eater which had two rows
of diamond-shaped plates on its back, as well as four long and deadly spikes
on its tail. There has been a lot of debate about the purpose of the plates
- they may have been for defence, for controlling temperature, or for display. It
ate plants on the ground, and had a very small brain.
Kentrosaurus - another stegosaur, 5m long,
found in Africa
200 - ichthyosaur skull -
found near Lyme Regis, on the 'Jurassic Coast'
200-145 - ammonites - the
ammonites seen in the workshop are Jurassic. The slab with many small
ammonites, which I found at Port Mulgrave in North Yorkshire, is about 190
million years old
190 - belemnites - Jurassic,
found on North Yorkshire coast
155 - Archaeopteryx - bird
154-153 - Brachiosaurus
154-150 - Diplodocus
150 - homeosaurus - lizard
150 - Megalosaurus footprint
145 - Stenophlebia aequalis -
144 - Pterodactylus antiquus -
140 - Mesolimulus walchi -
Many of the fossils sold in the workshop are Jurassic,
as there are a lot of Jurassic sites in Britain good for collecting fossils,
-Port Mulgrave, Staithes and Kettleness, all near Whitby
in North Yorkshire
-the Dorset coast (known as the Jurassic Coast), near
for details visit the
The Cretaceous was a very long period
(80 million years) in which many important and well-known animals and plants
evolved, such as Tyrannosaurus rex and
ended 65 million years ago when a 10km asteroid crashed into the Yucatan
Peninsula in Mexico, creating a 240km crater. This massive impact caused
tsunamis, earthquakes, widespread fires, acid rain, and a cloud of dust which blocked out
the sun causing a drop in temperatures. All of this led to the complete
extinction of the dinosaurs and many other species, such as the
pterosaurs, plesiosaurs, pliosaurs, and ammonites, and 60% of plant species.
The KT extinction (as it is known) left huge gaps in ecosystems, allowing
mammals to develop. Without the KT extinction human beings would not exist,
and the world might still be ruled by dinosaurs.
Sequoias, currently the largest trees in the
world (up to 110m high), first evolved in the Triassic and flourished in the
Bird evolution took off in the Cretaceous with many
species, some similar to Archaeopteryx and others like modern
birds. Many dinosaurs had feathers too; these did not first evolve for flight, but for warmth and to help movement, for example in gliding.
Dinosaurs from the early Cretaceous include:
Psittacosaurus - 2m, like a fat lizard with a
Iguanodon - 9m planteater with a vicous spike
on its thumb, has been found in England
Muttaburrasaurus - 7m, like an Iguanodon
but lived earlier, found in Australia
Gastonia - a 4m long ankylosaur, it had spines
all over its back for defence, and a thick skull so it might have
head-butted other members of the species.
Caudipteryx - 1m long, it looked a lot like a
bird, with a beak, long thin legs, and feathers.
Microraptor - another small
feathered dinosaur, related to Velociraptor, it probably couldn't fly but lived in
trees gliding from branch to branch
Deinonychus - a famous predator which was the
basis for the velociraptors in Jurassic Park (real velociraptors
were much smaller). Another feathered dinosaur, it was 3m long and very quick
and agile. It had a very long curved claw which may have been used to
puncture the neck of its prey, to stop it breathing and kill it.
Ornithocheirus - a gigantic pterosaur, with a
wingspan of up to 10m and a long jaw, it fed on dinosaurs.
Baryonyx - a 9m long theropod with a long head
like that of a crocodile, adapted for catching fish. Similar to later
Spinosaurus. Has been found in Britain.
Marsupials also evolved in the early
Cretaceous, e.g. Sinodelphys. Placental mammals
(in which babies grow in a womb) also evolved, e.g. Euomaia, from
which humans may be descended. Mammals still looked like rodents, however,
until the Paleocene (see below)
140 - first ceratopsian (horned) dinosaurs - ancestors
140-100 - diversity of stegosaurs and sauropods
decreases, diversity of ankylosaurs (e.g. Gastonia) and birds (e.g.
125 - first flowering plants - the first flowers were
tiny; flowers with large petals evolved 100-90 million years ago, e.g.
100 - first bees - evolved to pollinate flowers
90 - ichthyosaurs die out
90 - first snakes
80 - first ants and termites
The late Cretaceous was a period of many famous
dinosaurs, such as:
Spinosaurus - possibly the largest theropod,
16m long, it had a sail on its back and a long snout like a crocodile.
Plunged its jaws into water to catch fish. Seen in Jurassic Park III,
fighting a T rex
Carcharodontosaurus - 11m African therapod with
a huge skull - a terrifying predator, of which there were many in the
Giganotosaurus - 12m predator similar to T rex,
lived in Argentina and preyed on dinosaurs like Argentinosaurus.
Daspletosaurus - 9m long predecessor of T rex,
lived in North America.
Albertosaurus - 9m tyrannosaur which lived in
Tyrannosaurus rex - the most famous dinosaur of
all. Up to 13m long, weighed 5-7 tonnes, lived at the end of the Cretaceous
in North America. Probably both a scavenger and a hunter; evidence shows it
preyed on Triceratops.
has shown it had the strongest bite of any animal that ever lived, and could
chew up a small car. It had up to 58 teeth which were banana shaped and of
various sizes, up to 15cm (not including the root). Had tiny front arms but
a huge neck to supprt the enormous head, and a long tail for balance. Had
excellent vision and smell. A replica of one famous skeleton called
be seen in the Manchester Museum.
Tarbosaurus - 12m Chinese relative of T rex
with a less strongly-built skull.
Ornithomimus - 3m American therapod which looked
a bit like an ostrich - had long thin legs, feathers and big eyes
Gallimimus - 6m theropod like a large version
of an Ornithomimus. Lived in Mongolia. Long tail and slim legs mean
it was a fast runner. It is not known what it ate.
Oviraptor - small feathered theropod, very like
a bird, with a large squarish beak. Only one skeleton has been found, near
to its nest of 15 eggs.
Velociraptor - small feathered theropod, 2m
long. Had long claws, especially on its second toe, used for tearing flesh
of prey. Lived in Mongolia. Much smaller than the velociraptors shown in
Troodon - 3m North American theropod, preyed on
small lizards and mammals as well as baby dinosaurs. Fossils have been found
of adults sitting on nests of up to 24 eggs.
Argentinosaurus - The largest land animal ever,
a sauropod weighing up to 75 tonnes - ten times as much as a T rex. 30m
long, lived in Argentina. It was so big that predators like
Giganotosaurus could tear off chunks of its flesh and it would survive,
healing so the predators could return for a second course.
Ankylosaurus - 6m North American plant-eater,
well-protected by bony plates all over its back, and a large bony club at
the end of a long tail. It could deal death blows with a swing of its tail.
Euoplocephalus - huge, 7m relative of
Ankylosaurus, with a similar club tail to fend off predators.
Edmontosaurus - a very large (13m) duck-billed
dinosaur, or hadrosaur. The 'duck-bill' was toothless and was used to crop
large mouthfuls of vegetation. In its jaws however it had hundreds of small
teeth ideal for grinding plants.
Parasaurolophus - a 9m North American
hadrosaur, with a a long crest sticking out of the back of its head. The
crest was hollow and may have been used to make deep, resonating calls.
Corythosaurus - another hadrosaur with a crest,
but this one was a rounded plate shape on top of its head. It was probably
used to make calls.
Triceratops - a very large plant-eater, 7m long
and heavier (up to 12 tonnes) than the T rex which preyed on it. It had a
remarkable skull - some were over 2m long, with two horns up to a metre long
over the eyes, and a smaller one over the beak-like snout. As it grew older,
holes developed in the huge frill behind the head. Frills show signs of
injuries - from fights with other Triceratops, and from attacks by T rex -
one even had a horn bitten off by a T rex.
Protoceratops - a ceratopsian (or horned
dinosaur) like Triceratops, Protoceratops had a frill and
a small nose horn but no large horns. It was also much smaller, 2m.
Styracosaurus - another ceratopsian, 5m long,
with a remarkable array of six long spikes sticking up from its frill, as
well as large holes in the frill to reduce its weight.
Pachycephalosaurus - a 5m North American
plant-eater, it had a domed, very thick skull (its name means 'thick-headed
lizard') with bumps on the snout and back of the skull.
Other animals from this period include:
Deinosuchus - a gigantic crocodile, up to 9
tonnes and 12m in length. Lived in North America at the same time as
Daspletosaurus, but was more powerful. Probably hunted in the same way
as modern crocodiles, lurking at the water's edge.
Pteranodon - North American pterosaur, 1.8m
long with a wingspan up to 6m. It flew in flocks over water, hunting for
fish. Fish bones have been found in the stomach of some fossils, and the
long streamlined skull was ideal for diving into the water.
Quetzalcoatlus - the largest flying animal of
all time, a pterosaur with a 12m wingspan. Weighed only 250kg because
of air sacs inside its bones. Probably flew over land, hunting dinosaurs.
Named after an Aztec god.
Mosasaurus - a huge, 15m long sea reptile with
flippers and crocodile-like jaws. Its bite marks have been found on
ammonites and large turtles.
Elasmosaurus - one of the last plesiosaurs (sea
reptiles with flippers), 9m long. Over half its length was its neck, which
had 71 vertebrae - more than any other animal that has ever lived.
Kronosaurus - another giant sea reptile, one of
the last pliosaurs, 9m long with flippers and long jaws like a crocodile.
Hesperornis - a large, flightless sea bird from
North America. It had tiny wings, big feet and a long, toothed bill. It
could swim under water to catch fish.
Ichthyornis - a small (30cm) bird resembling a
seagull that used its sharp, toothed beak to catch fish.
Nemegtbataar - a small (10cm) mammal similar to
but not closely related to mice and rats.
112 - Sarcosuchus
81 - Pteranodon longiceps
75 - Oviraptor
65 - T rex,Triceratops
After the extinction of the dinosaurs there was room for
mammals to grow larger and diversify into many species. In the next 10
million years, a time known as the Paleocene, a huge number
of mammals and birds evolved. This continued in the following periods.
60 - first primates (our own ancestors), first
anteaters; first carnivorous mammals; first hedgehogs, shrews and moles
60 - many new flightless birds; first owls
55 - first grasses; many new species of flowering plants
55 - modern bird groups divesify - first song birds,
parrots, divers, swifts, woodpeckers
55 - first whale (Himalayocetus); first
rodents; first horses; first rabbits; first elephants
Some animals which lived in the Paleocene:
Titanoboa - an enormous, 13m long snake, the
largest land predator of its time
Presbyornis - a 1m tall bird looking like a
flamingo but with a wide bill - a distant relative of ducks and geese which
lasted for 20 million years
Plesiadapis - a small (18cm) creature similar
to a squirrel, but more related to primates
52 - first bats
50 - first brontotheres (large mammals); first rhinos;
first camels; primates diversify
40 - modern moths and butterflies
35 - grassland ecosystems develop
35 - major extinction of reptiles and amphibians
35 - whales diversify; new mammal groups appear -
glyptodons, ground sloths, dogs
35 - first hawks and eagles
Some animals which lived in the Eocene:
Anguilla - the first eel
Primapus - similar to a swift
Diatryma - a huge flightless bird, 2m
tall, which stalked prey through forests. It was the largest predator of its
time, larger than any mammal. It had a huge skull with a strong beak.
Uintatherium - a huge (3.8m) mammal like a
rhino with six rounded horns on its head.
Andrewsarchus - at 3.7m, the largest predatory
land mammal that has ever lived. It had a huge skull (over 1m) and looked
like a hyena.
Hyaenodon - not a hyena but a
large predatory mammal that looked like one
Hesperocyon - 80cm long North
American mammal that looked like a raccoon, with a long tail and short legs, but was in fact
the first member of the dog family, the Canidae. All dogs, wolves and foxes
evolved from this creature.
Icaronycteris - one of the first bats, 14cm
Palaeolagus - one of the first rabbits, but
very small - 10cm - and with shorter back legs.
Protorohippus - one of the first horses,
although it was only 38cm high and had toes rather than hooves.
Mesohippus - a 60cm tall horse with three toes.
Darwinius - a small primate from the middle
Eocene, a distant ancestor of humans
Eosimias - a tiny (5cm) primate from China
which looked like a marmoset
Ambulocetus - a 3m long ancestor of whales,
which had legs and could walk as well as swim. Its skull and teeth tell us
it was related to whales.
Moeritherium - an early member of the
Proboscidae family, from which elephants and mammoths evolved. It looked
like a hippo with a long snout.
55-45 - Lamna otodus, shark
50 - Archaephippus asper, a
50 - Propelodytes wagneri -
50 - midge in amber
30 - first pigs, first cats (that is, the felidae family; modern
pet cats are descended from the African wildcat from about 10,000 years
ago); brontotheres die out
25 - first deer
Paraceratherium - a gigantic
hornless rhinoceros, 8m long, 5.5m high, weighing 15 tonnes - the largest
land mammal that ever lived. Fed on the tops of trees like giraffes.
Miohippus - a type of horse
Stenomylus - a 1.5m tall
humpless camel from North America.
Eomys - a small, gliding rodent like a flying
20 - first giraffes; birds diversify
15 - first mastodon (an elephant-like animal); first
bovids (cow family); many types of very large animals in Australia
10 - savannahs and grasslands established, allowing many
species of grazing mammals to flourish, as well as carnivores which feed on
them; horses grow larger; small mammals and rodents diversify
10 - insects diversify, especially ants and termites
Species from the Miocene include:
Carcharodon megalodon - a
gigantic, 18m long shark, weighing about 50 tonnes. The largest predatory
shark that ever lived, its jaws were as tall as a man.
Argentavis - by far the
largest flying bird ever, with a wingspan of 8m. Looked like a condor, and
lived in Argentina. Probably a scavenger, it had a huge beak and claws to
rip open carcasses.
Thylacosmilus - a large (1.5m)
predatory marsupial with two enormous front fangs. Lived in South America.
Enaliarctos - 1.5m long North
American ancestor of seals, it had flippers and swam in the sea but was
active on land too.
Teleoceras - a large, 4m long
rhinoceros from North America. It had one small horn on the tip of its nose.
Hundreds of fossils have been found.
Merychippus - a 1.1m tall
horse that lived on the new grasslands of the Miocene. A fast runner, it was
the first equine to have just one hoofed middle toe on each foot. Modern
horses are descended from Merychippus.
Pliohippus - a descendant of
Merychippus, but not an ancestor of modern horses.
Slightly smaller than a modern horse.
Deinotherium - a huge (4.5m
tall) relative of mastodonts (similar to elephants). Its tusks curved down
and back from the front of the lower jaw, and may have been used to hook
branches to drag them down and reach the leaves. The trunk was much shorter
than an elephant's. Weighed about 14 tonnes, more than a modern elephant.
Gomphotherium - like a small
elephant (3m tall), with a long flat skull and four tusks - two long
straight tusks on the upper jaw and two shovel-like tusks on the lower jaw.
Mammoths evolved from these creatures in the Pliocene.
Proconsul - a possible
ancestor of both monkeys and apes, 65cm long, lived in Africa. Like a monkey
it was a lightly-built tree-dweller, and fed on fruits. Like an ape it had a
large brain and no tail.
Sivapithecus - an ape related
Dryopithecus - an ape the size
of a monkey (60cm) but built like a chimp. Could walk on all fours like a
chimp, but also swing in the trees.
7 - Encope californicus -
7-6 - first hominin - Sahelanthropus -
brain size 360ccm - an ape which may have
walked on two legs, and may be an ancestor of humans. Found in Chad, Africa
(all hominins up to 2 million years ago lived in Africa)
6 - Australopithecines diversify:
6.1-5.8 - Orrorin - may be
the oldest known biped (walking in two legs), closely related to chimps as
well as humans
5.8-5.2 - Ardipithecus kadabba
- as with the previous two, it is not certain if this was a human or chimp
Many hominin species evolved in the Pliocene
(see right). About 2
million years ago the Australopithecines died out and the genus Homo
evolved, beginning with Homo habilis. Many other
fascinating and sometimes enormous animals also appeared in this period:
Castoroides - a giant ice-age
beaver, 2.5m long. It had 15cm long front teeth, weighed up to 100kg and lived in
Glyptodon - a 2.5m long
relative of armadillos, with a rounded and well-protected body covered in
tiles up to 2.5cm thick. Lived in South America.
Megatherium - a giant ground
sloth, 6m long and weighing 4 tonnes. It was as big as an elephant and
covered in long hair. It had long forelegs with enormous claws for gripping
trees and fending off predators.
Equus - the genus which
includes modern horses, zebras and donkeys.
Mammuthus - a successful genus
of elephant-like creatures that survived throughout the Pliocene and
Pleistocene; the last mammoths lived on Wrangel Island in the Arctic Ocean until
1700BC. The Steppe mammoth (600,000-370,000 years ago) was the largest,
growing 5m tall with tusks up to 5m in length. The famous woolly mammoth
weighed 8 tonnes and was covered in a thick layer of hair to keep it warm.
The hair was similar in colour to that of humans - it could be brown, ginger
or blond. Several frozen mammoths have been found in excellent condition.
Scientists in Japan are trying to clone one to bring the mammoth back to life,
like the dinosaurs in Jurassic Park. Mammoths may have been hunted
to extinction by humans, who ate their meat and used the bones and tusks to make
tools and works of art.
Coelodonta - an ice-age woolly
rhinoceros, 3.7m long with a thick coat of shaggy hair. Had two long horns,
probably used to shift snow when foraging. Died out at the end of the ice
age, about 10,000 years ago.
Megaloceros - a large deer
(2.7m long) with huge antlers even larger than those of a moose. Died out at
the end of the last ice age.
Gigantopithecus - a huge ape,
3m tall, built like a gorilla but much bigger - weighed 540kg. Lived from 1
million to 300,000 years ago in Asia. Related to orang-utans.
4.4-4 - Ardipithecus ramidus
- a bipedal chimp-like ape, its skull was balanced over its spine (as in
humans) and its toes were adapted for walking rather than grasping
4.2-3.9 - Australopithecus anamensis
- another ape-like bipedal hominin from Eastern Africa
Australopithecus afarensis - brain size 380-485ccm,
height up to 1.5m. Thought to be an ancestor of humans; a very famous almost
complete skeleton nicknamed 'Lucy' was found in 1974. Brain similar was size to
3.6-3 - Australopithecus bahrelghazali
- found in Chad, known only from fragments of a jaw and teeth.
Australopithecus africanus - brain size 428-625ccm,
height 1.4m. Another ape-like bipedal human ancestor, with a small brain and
human-like teeth. The first early hominin ever found (in 1924).
Kenyanthropus platyops - lived alongside other
3-2 - Australopithecus garhi - brain
size 450ccm - may or may not be one of our ancestors. Possibly the
first hominin to use stone tools.
2.5 - Paranthropus
aethiopicus - lived alongside early Homo species, so we are
not descended from them. Had strong jaws for chewing tough seeds and
2.5-1.2 - Paranthropus boisei -
another ape-like hominin with even stronger teeth than
2-1 - Paranthropus
robustus - another species of Paranthropus, lived in southern
2.2-1.6 - Homo habilis - brain size
500-650ccm, height up to 1.3m; the first member of the genus
Homo, to which we belong. The name means 'handyman', as stone
tools have been found with fossils. Its brain was larger than the
australopithecines whch came before, and its use of tools allowed it to
access new foods, such as nuts, meat and bone marrow. Its teeth grew smaller
as it needed them less for grinding tough vegetables.
Homo rudolfensis - brain size 600-800ccm, height 1.6m. Closely
related to Homo habilis but little is know about it.
10,000 years ago
Aepyornis - a giant (3m tall)
flightless bird like an ostrich. Nicknamed the 'elephant bird', it was the
largest bird that ever lived, weighing 400kg. Its eggs were 34cm wide.
Probably hunted to extinction by humans quite recently, when Europeans
arrived in Madagascar.
Megalania - a giant monitor
lizard, 8m long, like a huge Komodo dragon. Big enough to eat any of the
large ice-age mammals of Australia. Had long, sharp teeth and weighed
Dinornis - a type of moa, a
group of very large (3.6m tall) flightless birds from New Zealand. They were
wiped out by the Maoris in the 16th century, as a result of hunting and
Teratornis - a huge bird like
a condor but larger, with a 4m wingspan, whch lived in North America. Died
out about 10,000 years ago when many of its prey also died out.
Arctodus - a giant bear, 3.4m
long, weighing 900kg. A fast runner, with very powerful jaws. Lived in North
America, and died out at the end of the last ice age, like many other large
- the dire wolf, similar to a modern grey wolf, but heavier - 80kg. Lived in
North America, died out at the end of the last ice age, perhaps because of
the spread of humans, wiping out the wolves' food sources.
Smilodon - a famous cat, known
as a sabre-toothed tiger due to its two very long canine teeth, used for
stabbing prey in the throat or belly then ripping it open. 2m long and about
400kg in weight, very strong and heavily built compared to modern big cats.
Died out, perhaps because of competition from humans, at the end of the last
1 - Coral from Australia
30,000 years ago - Bison femur, rib and vertebra found
on the Isle of Wight
1.8-0.6 - Homo ergaster -
brain size 600-910ccm, height up to 1.85m. A very important species, from
which we are descended. Its name means 'workman', as its stone tool use was
more complex than any hominin before. It was tall and slender, with a
downward pointing nose - all adaptations for living on dry, hot savannahs.
Probably the first species to migrate out of Africa, 1.8 million years ago,
into Europe and Asia.
1.8-50,000 years ago - Homo erectus
- brain size 750-1300, height up to 1.8m. Probably descended from
Homo habilis, a very successful species that eventually
lived alongside modern humans and may have hunted them. Looked similar to
humans, although with a thick, heavy brow, large teeth and a less distinct
chin. Much bigger brains than previous hominins. Either spread into Asia
from Africa, or evolved in Asia and returned to Africa.
Homo antecessor - brain size 1000ccm, height up to
1.8m. Lived in Europe (fossils have been found in Spain), but probably not
an ancestor of modern humans.
0.6-0.2 - Homo
heidelbergensis - brain size 1100-1400ccm, height up to 1.8m.
The last common ancestor of both Homo sapiens (us) and Neanderthals. Tall,
well-muscled, with heavy limb bones, suggesting tough physical activity like
hunting. May have been able to speak. Found in Africa and Europe.
350,000-30,000 years ago - Homo neanderthalensis -
brain size 1400ccm, height up to 1.7m. Neanderthals are a famous hominin,
descended like us from Homo heidelbergensis. They
lived at the same time as us but it is not known if the two species
interacted. They were intelligent and buried their
dead in graves. Unlike us they had low, sloping foreheads, very large noses
and forward-projecting faces. They were physically strong and stocky, and
well adapted to the cold environment of Europe. Hunted large and dangerous
animals, like mammoths.
400,000-125,000 - archaic Homo
sapiens - were similar to earlier hominins, having large
faces, heavy brow ridges, thick bones and not much of a chin. Evolved
into modern humans about 150,000 years ago.
150,000 years ago to present
- Homo sapiens - brain size 1000-2000ccm, height
up to 1.85m. More modern features of humans gradually evolved from about
250,000 to 125,000 years ago - a chin, smaller brow ridges, smaller faces,
and higher, rounded braincases. Developed sophisticated tools, art, and
jewellery: e.g. items discovered in a cave in south Africa from 73,000 years
ago: pieces of red ochre engraved with geometric patterns, beads made of
pierced shells, and finely made bone tools. Evolved in Africa and moved out
about 60,000-40,000 years ago, ending up in Europe, Asia, in Australia
about 45,000 years ago and in North America about 16,000 years ago.
Beautiful cave paintings found in Europe date to as much as 30,000 years ago
(the Chauvet caves in France).
10,000 years ago-present
The Holocene is the period in which human beings
developed agriculture (farming) in the near east, which led to settled
communities and stone buildings (the earliest we know is Gobleki Tepe, in
Turkey, a stone-carved temple from 12,000 years ago). The first cities and
civilisations were in Sumer (Iraq) and Egypt.
Note - there are two main periods after the extinction of the
dinosaur: the Paleogene and the Neogene. Usually however we use the periods
which are shorter. The Paleogene (65-23 million years ago) is made up
of the Paleocene, the Eocene and the Oligocene. The Neogene (23 million
years ago to the present) is made up
of the Miocene, the Pliocene, the Pleistocene, and the Holocene.