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Time periods

When were the periods you refer to?

It is a matter of different periods during the last couple of hundred million years. I will explain each of them. Please note that the continents have moved through the ages. However, this process is so slow it takes millions of years to make any considerable difference.

1. The Triassic was 252 – 201 million years ago. During most of the period there was only landmass large enough to be called a continent. It has been named “Pangaea” which means “all land”. It was essentially a fusion of most of larger landmasses which exist today. During this period climate was so warm that no polar ice caps existed. Because Pangaea was so very large it was also a dry world.
1.0.1. The first episode of Walking with Dinosaurs takes place toward the end of the Triassic. It takes place in present-day south-western United States. The area was then a tropical savannah with the wet season during the northern hemisphere winter. There PostosuchusPlacerias and the cynodonts lived.

2. The Jurassic was 201 – 145 million years ago. During this period Pangaea started to split. The southern part of the North Atlantic formed dividing Africa from North America. This way Pangaea split in a northern and a southern part. The maximum distance to the sea decreased which made the climate wetter. At the end of this period a small icecap formed in present-day Antarctica. In contrast there was no northern icecap.
2.0.1. The second episode of Walking with Dinosaurs takes place toward the end of the Jurassic. It takes place in present-day western United States. The area was then covered by tropical and subtropical woodlands and plains. (Different areas may have got most of their rain during different parts of the year.) There Brachiosaurus and Diplodocus lived.
2.0.2. The third episode of Walking with Dinosaurs takes place just at the end of the Jurassic. It takes place in Central Europe. The area was then largely covered by shallow and warm seas. No-one of the animals on the list lived there then.

3. The Cretaceous was 145 – 66 million years ago. During this period Pangaea’s two halves split into different continents roughly corresponding to today’s. The exception was Australia and Antarctica which still stuck together as before. At the beginning there was a south polar ice-cap but it seems to have melted away altogether. During the middle and late Cretaceous there was probably no ice-cape at all.
3.0.1. The forth episode of Walking with Dinosaurs takes place in the beginning of the Cretaceous. It takes place around the coasts of the North Atlantic which had recently started to form. Coasts and islands where more or less covered with subtropical monsoon forest. Here Utahraptor and Iguanodon lived.
3.0.2. The fifth episode of Walking with Dinosaurs takes place at the middle of the Cretaceous. It takes place in southern Australia. The area then laid south of the Antarctic Circle. But since the climate was so warm I was covered with temperate open woodland. There Leallynasaura and Koolasuchus lived.
3.0.3. A special episode made later takes place towards the end of the Cretaceous. It takes place in present-day eastern Central Asia. The area was subtropical and covered with woodlands. There Mononykus and Therizinosaurus lived.
3.0.4. The sixth and last episode of Walking with Dinosaurs takes place at the very end of the Cretaceous. It takes place in an area corresponding to present-day Montana in the USA and surrounding areas. The area was then covered with subtropical monsoon forest. There Ankylosaurus and Tyrannosaurus lived.

4. The Tertiary (66 – 2.6 million years ago), with the frequently used subdivisions:
4.1. The Palaeocene was 66 – 56 million years ago. No episode of Walking with Beasts takes place during this period.
4.2. The Eocene was 56 – 34 million years ago. This period had the warmest climate during the last 65 million years.  It was so hot it is hard to comprehend how it could become so hot. Finally, at the end of the period the Antarctic ice sheet started to form. By then Australia had parted from Antarctica. The northernmost part of the Atlantic had also started to form. This way the continents we have today had arisen.
4.2.1. The first episode of Walking with Beasts takes place in early Eocene. It takes place in I present-day Germany. The area was then covered with subtropical rainforest. There Propalaeotherium and Leptictidium tobieni lived.
4.2.2. The second episode of Walking with Beasts takes place towards the end of the Eocene. It takes place in present-day Pakistan which was then partly covered by seas. The coasts had mangroves and plains where Embolotherium andrewsi lived.
4.3. The Oligocene was 34 – 23 million year ago. During this period the climate continued to cool down. This also meant a drier climate since drier air can hold less moisture.
4.3.1. The third episode of Walking with Beasts takes place towards the end of the Oligocene. It takes place in present-day Mongolia. The area was then covered with subtropical savannah with the rainy season during the northern summer. There ParaceratheriumCynodictisEntelodon and Hyaenodon gigas lived.
4.4. The Miocene was 23 – 5 million years ago. No episode of Walking with Beasts takes place during this period.
4.5. The Pliocene was 5 – 2.6 million year ago. By then it was so cold the Greenland ice sheet had begun to form. However, it was usually considerably warmer than it is today.
4.5.1. The forth episode of Walking with Beasts takes place towards the end of the Pliocene. It takes place in present-day Ethiopia. The area then had tropical open woodlands and savannahs. Besides a few animals existing today there lived Dinofelis barlowi and Ancylotherium hennigi.

5.0. The Quaternary consists of the last 2.6 million years. The continents have barely have time to move at all during this relatively short period. In contrast the climate has varied much between long and cold ice ages and warmer periods between them. Furthermore, the world seems to have become colder for each ice age period.
5.0.1. The fifth episode of Walking with Beasts takes place one million year ago. It takes place in present-day Paraguay. The area was then a tropical savannah. Besides some animals still in existence there lived DoedicurusMacrauchenia patachonicaMegatherium americanum and Smilodon populator (sabre-toothed cat).
5.0.2. The sixth and last episode of Walking with Beasts takes place 30,000 years ago. It takes place in Western Europe. Due to the then much colder climate large parts of Northern Europe was covered with ice. South of the ice was a band of tundra. This was followed by plains with a mix of plants now growing on tundra’s and steppes. This was in turn followed by open woodlands of conifers. Together with animals existing today there lived Coelodonta antiquitatis (wolly rhino) and Megaloceros giganteus (giant deer).

Please note that the present-day humanity has just existed for 300,000 years. Human as biological genus has existed only during the Quaternary. As such humans have not been present during any larger geological changes.

Last changed the 24th of May 2019.
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