Triassic and Jurassic periods
245 to 144 million years ago

247 MILLION YEARS AGO

 
The interior of the great supercontinent appeared more desert-like because conditions on land were initially very hot and dry. Only the coastal regions were humid enough to support ground-covering ferns, tree-like ferns such as Dicroidium, conifers and cycads, and an increasingly more diversified and flourishing insect population.

Then the conditions began to cool down a little and rainfall increased. Soon the plants edged its way towards the interior of the supercontinent until much of the land became a huge tropical forest.

 

245 MILLION YEARS AGO

 
Again, there was another tremendous burst in animal numbers over the next few million years. But what differed in this sudden burst (in geological terms) in life compared to the Cambrian period was the greater numbers of animals of a particular theme rather than an all out innovate stage of evolution.

As Roger Lewin, author of Complexity: Life at the Edge of Chaos, wrote:

'...there have been tremendous bursts of innovation...in the history of life, mostly in the wake of mass extinctions. For instance, following the Permian extinction some 250 million years ago, in which an estimated 96 percent of existing species perished, the rate of innovation almost matched that of the Cambrian. But the innovation was principally variations upon existing themes; no major new themes were added. In the Cambrian, by contrast, innovation was largely at the level of producing new themes, with variations upon them being relatively minor.' (1)

 

235 MILLION YEARS AGO

 
With many new predators now competing for the abundant supply of food on land (KFC's has nothing compared to these times), a number of reptiles and a few mammal-like animals decided to return to the sea. However, those who were able to survive on land evolved into many different species to help increase their survival rate. (2)

Among the land-based creatures that successfully evolved at this time included the first true, hairy-like mammals and the first dinosaurs. But it would be the dinosaurs who would dominate life on the great supercontinent (known as Pangaea) for the next 170 million years.

Evidence to support the existence of this great supercontinent can be seen from the fossil evidence. The fossils show animals of the Triassic Period were widespread and remarkably alike throughout all the continents of the world. But later, after the supercontinent broke up during the Jurassic Period at around 210 million years ago, the animals diversified into more unique forms based on locality.

Earth in the Early Triassic era around 237 million years ago. Image © 1997 C.R. Scotese is available from http://www.geologie.uni-stuttgart.de/down/maps2/pl7.jpg.

 

230 to 180 MILLION YEARS AGO

 
The Sun is known to take approximately 225 million years to travel one revolution around the Milky Way. Thus nearly one revolution around the galaxy ago, the Earth was just starting to be dominated by the great reptiles known as dinosaurs.

The early dinosaurs (the name comes from the two Greek words deinos, "terrible", and saurous, "lizard") were small creatures by our standards, but they later evolved and diversified into some of the largest land animals that ever lived. For more than 50 million years, huge plant-eating dinosaurs like the Brontosaurus, Briachiosaurus and Sauropods, and large terrifying meat-eaters such as the Tyrannosaurus Rex roamed the Earth.

For nearly 100 million years, early mammals lived in the shadow of the great dinosaurs. Shown here is an artist impression of a Tyrannosaurus Rex chasing an ostrich-like creature called a Struthiomimus (centre). Hiding in the fern trees is a Megazostrodon (foreground). Source: Reader 1986, p.125.

This was a time when size did matter. Not only was there a plentiful supply of food on the great supercontinent to support very large dinosaurs on land - a kind of giant "smosgasbord" of fresh meat and vegetation just sitting out there ready for the taking, although competition for the food was still considered extremely fierce at this time - but also there was a survival bonus: the larger the animal can become, the more easier it is for the animal to survive the attack of most predators.

A meat-eating Allosaur tries to take one of the young dinosaurs from a herd of Sauropods, risking life and limb in doing so. Source: Norman 1991, p.93.

Despite size being an important factor in the survival of many dinosaurs, they had one major weakness: the reptiles did not develop a quick and effective internal body temperature-regulator. But this did not seem to worry the dinosaurs for there would be an extremely persistent period of very warm, moist tropical-like climate existent throughout much of the world for the next 50 million years.

A Baryonyx searches the forest floor for fish and other animal prey. Source: Norman 1991, p.108.

Mammals, on the other hand, did develop a primitive internal body temperature-regulator and so were much better adapted to the lower temperatures existent at the extreme northern and southern latitudes on Earth, on mountain-tops, deep inside certain caves, or during the night where the great dinosaurs were probably more sluggish or the mammals could not be easily seen by the reptiles.

In fact, it would not have been too unusual for the mammals to come out at night to hunt and scavenge for food near the polar regions (or to take up residence high up in the tropical forests), while the dinosaurs kept themselves mainly to the warmer areas on the ground near the tropics and/or around lakes and shallow inland seas (which would have absorbed a lot of heat during the day).

Land-based mammals of this era were small creatures living secretly and did not evolve into larger more complex creatures until the great dinosaurs disappeared.

NOTE: Any large mammal of this era would have probably been wiped out due to the highly developed and powerful muscle structure of the two-legged carnivorous dinosaurs which gave these terrible lizards excellent speed (in a roughly straight line for the larger predators) to capture practically all large, cumbersome prey. (3)

 

210 MILLION YEARS AGO

 
The great supercontinent began to split apart.

Huge prehistoric forests comprising of cycads and conifers together with a thick undergrowth of ferns covering the ground were on the increase and dominated much of the great supercontinent. The evidence to support the size and abundance of these forests can be seen today from the presence of great coalfields in Europe, Australia and other parts of the world. (4)

 

190 to 195 MILLION YEARS AGO

 
A seaway separated the northern continent (North America, Europe and Asia) known as Laurasia, with the southern continent (South America, Africa, Australia, Antarctica, and India) known as Gondwana land. (5)

Earth in the Early Jurassic era around 195 million years ago. Image © 1997 C.R. Scotese is available from http://www.geologie.uni-stuttgart.de/down/maps2/pl8.jpg.

A team of Chinese and American scientists have discovered in the rich fossil beds of Yunnan province in China a 12mm long 195 million-year-old skull from a tiny animal no larger than a paper clip. What makes this prehistoric skull so remarkable is its bone structure. According to the scientists, this is the oldest known creature having the distinctive and crucial mammalian feature of having a one-boned jaw for better control of chewing and three middle-ear bones for improved hearing. Furthermore, the name given to this creature - Hadrocodium wui - means "full head" because of the skull's relatively large brain-holding capacity. Scientists believe a large brain did develop inside this skull because the animal utilised these distinctive anatomical features for its survival.

Zhe-Xi Luo, a member of the American team from the Carnegie Museum of Natural History in Pittsburgh, Pennsylvannia, said:

'Hadrocodium could be our distant cousin, an early mammal that existed alongside the ancestor of living mammals.' (6)

 

190 to 136 MILLION YEARS AGO

 
In the midst of the great dinosaur age at around 190 million years ago, the extraordinary abundance of plant life covering the great northern and southern supercontinents, as indicated by fossils dated to this period, gives evidence of a more moist and warmer climate than today. It was so warm that even polar ice caps may not have existed!

The leaf of a ginko (top) compared to a fossilised version (below). By counting the number of microscopic pores on the fossilised leaf where carbon dioxide is taken in, scientists have been able to calculate the amount of carbon dioxide in the atmosphere of 190 to 160 million years ago and thus accurately reconstruct the primeval Jurassic climate and forests. Basically the fewer the pores, the less carbon dioxide the plants require to grow which in turn shows a much higher concentration of carbon dioxide in the air. On examining the fossilised leaf, scientists noticed a much lower pore count than the ginko leaves grown naturally in today's climate. Through controlled experiments, scientists have been able to calculate the amount of carbon dioxide needed in the air to create a ginko plant of the equivalent number of pores as in the fossilised version. The concentrations of carbon dioxide was 4 to 5 times higher than at the start of the industrial revolution in the 1800s. Source: Smith, Dr Richard. Crude — The incredible journey of oil: Catalyst. 18 May 2007 (televised 24 May 2007).

Scientists believe the origin of this supergreenhouse effect came from the great volcanoes dotted along major cracks in the Earth's crust caused by the breakup of the great supercontinents. Scientists say the great supercontinent of the south began to break-up and drift apart some 210 million years ago. This was the time when the mid-Atlantic ridge was born between 180 and 210 million years ago. By 160 million years ago, the air was laden with four to five times the carbon dioxide levels than existed just prior to the industrial revolution of the 1800s (or 2.5 times the quantity we see today due to humans burning fossil fuels).

The reason why the supercontinent had to break up around 210 million years ago is not precisely known. It is possible that another asteroid may have collided with the Earth (probably over water this time as there is no evidence to show there was a sudden reduction in worldwide temperatures for a brief moment which would have ended the great dinosaur age). Certainly it is known that another major and widespread extinction had occurred nearly 214 million years ago (8) coinciding at about the time of the great supercontinent breaking up. Or maybe it has to do with the way the strong internal heat currents in the magma of the Earth can break the crust into individual, free-moving tectonic plates. We can only speculate at the reason for the break-up of the great supercontinent.

Artist impression of Earth nearly 160 million years ago. Clouds would have covered more of the planet at this time than shown here because of the supergreenhouse effect and the great plant life dominating the supercontinents. Source: Smith, Dr Richard. Crude — The incredible journey of oil: Catalyst. 18 May 2007 (televised 24 May 2007).

At any rate, scientists are certain the weather of 160 million years ago was generally uniform and differences between summer and winter were not apparent. The temperatures at the poles rarely dipped below 10 to 15°C (7); whereas the levels of rainfall were very high, giving rise to more lush and denser tropical plant life across the great supercontinents. In fact, these wet conditions on land were made possible because of extensive plant life covering the supercontinents which in turn retained more moisture on the ground and provided sufficient humidity in the air to fall as rain along certain mountain ranges.

However, after the end of the Jurassic Period, nearly 136 million years ago, conditions began to get cooler. With fewer volcanoes and enough plant life absorbing carbon dioxide from the atmosphere together with some mountain-building and changes in the position of continents on the Earth's surface, we see for the first time in more than 50 million years how the Earth began to form polar ice caps.

Earth in the Late Jurassic era around 152 million years ago. Image © 1997 C.R. Scotese is available from http://www.geologie.uni-stuttgart.de/down/maps2/pl9.jpg.

Contradicting the traditional view that mammals at this time were small rodents scampering through the undergrowth searching for food and hiding from the dinosaur predators and weren't adventurous enough to diversify into other forms, a team of researchers from the Chinese Academy of Geological Sciences in Beijing and Carnegie Museum of Natural History in Pittsburgh headed by Dr Qiang Ji of Nanjing University reported in the 24 February 2006 journal Science the fossilized remains of a 60cm long platypus and Beaver-like mammal living 164 million years ago.

The well-preserved fossilized remains was found in 2004 in the inner Mongolian region of China known as Liaoning province.

Aptly named Castorocauda lutrasimilis meaning "beaver tail" (castoro is latin for "beaver" and cauda for "tail") and "like a river otter" (lutra stands for "river otter" and similis meaning "similar") by the discoverers, this interesting cat-sized creature is believed to be the largest known mammal living in the Jurassic period. It possesses limbs claimed to be well-developed for aquatic life including soft-tissue webbing in the hind feet as purportedly seen in the fossil. In fact, preservation of some soft tissue and fur imprints must be seen as a testament to the quality of the find compared to other fossils dated to this period. Scientists suspect the animal swarm in rivers and lakes like a platypus, and built nests in burrows along the shore. However its head looked more like a rodent with a broad scaly tail like a beaver, and its sharp teeth looked like an otter designed to eat fish and insects.

Artist impression of Castorocauda lutrasimilis (Courtesy Mark A. Klinger/CMNH).

As Dr Zhe-Xi Luo, one of the discoverers of the fascinating creature and curator of vertebrate paleontology at Carnegie Museum of Natural History, said:

'Its lifestyle was probably very similar to the modern day platypus. It probably lived along river or lake banks. It doggy-paddled around, ate aquatic animals and insects, and burrowed tunnels for its nest.' (The Canberra Times: Platypus-like mammal fossil surfaces. 25 February 2006, p.18.)

The existence of this animal living in the watery environment has pushed back "the mammalian conquest of the waters by more than 100 million years" according to Dr Thomas Martin, an authority on early mammals at the Senckenberg Research Institute in Frankfurt, Germany.

 

125 MILLION YEARS AGO

 
In May 2005, palaeontologists in Utah, USA, claim they have found the missing link in a new species of dinosaur with feathers showing that around 125 million years ago some meat-eating reptiles slowly evolved into plant-eating types. The new feathered dinosaur species supporting this claim is called Falcarius utahensis. It literally means "sickle maker from Utah".

Standing not much taller than 1 metre and roughly 5 metres in length from head to tail, the near complete remains of Falcarius showed it had 10 cm long claws like sickles as commonly found in meat eaters. However the crucial link to herbivores was in the numerous small teeth lining its jaw. Instead of large, sharp pointy teeth to cut meat, the creatures entire teeth structure were more delicate and smaller to handle softer plant materials.

The possibility exists that this species, despite its sinister-looking carnivorous appearance, may have exclusively feasted on plants and nothing else. But no one knows for sure.

As Matthew Carrano, the curator of dinosaurs at the National Museum of Natural History (part of the Smithsonian Institution in Washington), said:

'It's the strangest looking dinosaur you can imagine.

'It's as if you sewed the dinosaur together from pieces of other dinosaurs.' (The Canberra Times: 'Patchwork' dino solves evolution puzzle. 7 May 2005, p.21.)

Could the evolutionary progression to plant-eaters (and of the feathers) be an indication that some animals were living in cooler areas frequented by fewer predators away from the oversized daily reptilian bloodbaths taking place daily in the hotter areas of the planet?

## SPECIAL UPDATE ##
23 November 2006
Like a giant genetic experiment going wild, another feathered dinosaur had four wings and another creature could do more than glide from one tree to another — it could flap its wings. A wealth of interesting fossils are now starting to emerge from China.



NOTES

  1. Lewin 1993, p.65.

  2. In religious terms, we call this searching for love and balance, or ultimately the experience and knowledge of the one true God of the universe. As one religious leader said, "Is it not written in your scriptures that you are gods?"

    In making the distinction between "gods" and "God" it shows that we are imperfect creatures seeking a more perfect existence to escape the suffering and pain we go through throughout evolution and in life.

    While creatures have suffered in the past and have found a way to survive better and genetically adapt more efficiently as their best solution, every living creature is actually searching for the love that would see them have what they need to live for as long as possible in the universe. To transcend beyond our survival needs to one of being happy and able to apply our minds to broader issues is truly the definition of freedom. It is the ultimate form of balance and love.

    As human beings, we must be more creative to try different ways to survive so that all living creatures can experience this universe in peace and love.

  3. To survive these dangerous dinosaurs would have required sufficient intelligence in the mammals to overcome their initial and instinctive fear to run away. Part of that development in intelligence would have involved learning how to camouflage and/or hide themselves in the plant world or (heaven forbid!) in some of the huge waste piles left behind by the great dinosaurs for a long enough period of time so that hopefully the short-term memory of the predators would get them to forget about the prey. Otherwise, they had to adapt to the cooler conditions where dinosaurs were smaller in size and less prolific in numbers.

  4. Most of the crude oil we extract underneath the ground and process to make the petrol and oils for running our 20th and early 21st century motor vehicles originally came from the great plant life (and some dead prehistoric animals) that existed during this era.

    At first the supergreenhouse effect over the great supercontinents created a prehistoric environment of high humidity and heat needed to produce heavy rainfall over the land masses. As the rains fell from the heavens, many great Amazonian-like rivers swelled in volume, carrying with it a flood of nutrients consisting of nitrates and phosphates from animal waste and decaying plant life until the waters reached the seas and oceans of Tethys. But this wasn't a local phenomena. Evidence gathered by Professor Hugh Jenkyns of Oxford University showed the events of nutrient-rich waters reaching the seas occurred in what is now the Pacific ocean. In fact the entire oceans of the world was awashed in this nutrient-rich waters.

    Here, the nutrients combined with carbon dioxide dissolved in the water from the hot tropical air and the sunlight penetrating the waters, fed the trillions upon trillions of tiny plant organisms known as photoplanktons and microscopic animals called bacteria.

    Examples of photoplankton today as it would have appeared in the shallow seas of 160 million years ago. Source: Smith, Dr Richard. Crude — The incredible journey of oil: Catalyst. 18 May 2007 (televised 24 May 2007).

    Millions of years would pass as these tiny creatures lived out their lives near the surface of the seas and oceans feeding on the great fertiliser that is Jurassic park of the great supercontinents and they were multiplying in vast numbers. At the mouths of great rivers one can see the massive areas of green plant life in the shallow seas and much of the oceans as it absorbed the nutrients.

    Together with other sea-faring creatures such as fish and prehistoric reptiles, the death of these creatures would see the organic matter drift to the bottom of the ocean. Layers upon layers of this organic matter built up over time. When combined with an almost zero flow of water over the shallow seas, we see one other factor favouring the formation of oil. Water deep down become oxygen deprived.

    Also the organic matter on the floor fed a entirely different type of bacteria not requiring oxygen to survive. This bacteria emitted as a waste product hydrogen sulphide — a toxic substance to animals and plants. Any life that existed in these shallow seas had to remain near the surface to get its food and oxygen.

    Some of the ancient fish and other animals swimming and eating the photoplankton and each other in the prehistoric oceans of 160 million years ago. Source: Smith, Dr Richard. Crude — The incredible journey of oil: Catalyst. 18 May 2007 (televised 24 May 2007).

    The toxic nature of hydrogen sulphide and lack of oxygen in the deeper waters because of the stagnancy of the shallow seas is what prevented the organic matter from being disturbed by animals. The hydrocarbon-rich material layed on the bottom, accumulating in vast quantities. As Dr Jeremy Leggett, a former exploration geologist, said:

    'The oceans then were just replete with organic matter. These microscopic plants proliferated in quantities that the world hasn't seen for millions of years. And they were also able to be preserved because these oceans were very prone to stagnation. So there was much less oxygen in the waters, much less overturning of the water, the organic would sink to the bottom and be preserved and then it would be buried by rapidly accumulating sediments.' (Source: Smith, Dr Richard. Crude — The incredible journey of oil: Catalyst. 18 May 2007 (televised 24 May 2007).

    Dr Jeremy Leggett

    Over the next 100 million years, the carbon-rich layers of sticky black mud became compressed. As the seas receded, the layers dried up into a black rock-like shale and later pushed deeper into the Earth where it can be cooked by the Earth's magma at the right temperatures and pressures to eventually form a thick black crude liquid known as oil, or black gold in today's commercial world.

    As Dr Jeremy Leggett, a former exploration geologist, explained it:

    'When it gets to a certain depth of burial some thousands of feet below the surface, it physical cooks by the pressures and the temperatures you get there and the organic carbon cracks and it goes from this original material to light wheat crude as oil people tend to call it.' (Source: Smith, Dr Richard. Crude — The incredible journey of oil: Catalyst. 18 May 2007 (televised 24 May 2007).

    Around 160 million years ago, Saudi Arabia was part of the great shallow seas of the Tethys-Ocean. Today, Saudi Arabia has become a desert. And below this country lies the world's biggest deposit of crude oil measuring approximately 35 kilometres wide and 175 kilometres long. Nearly two-thirds of the world's oil supplies can be found in Saudi Arabia. As of 2007, humans are fast using up this oil reserve.

    While other countries have gone past the oil peak and are facing the end of oil production (the US own oil supplies will run out by 2050 after reaching peak oil in the 1970s), it is only now (ie. 2006) that Saudi Arabia has past its own oil peak. The end of the oil age has truly begun.

    Should humans continue the trend in burning the oil in such great quantities, soon the carbon dioxide in the oil will be released in sufficient numbers to create a new supergreenhouse effect, far warmer than the greenhouse conditions we are experiencing today. However, this time, humans will not benefit from the plant life on land to provide shade, retain moisture on the ground, and grow adequate food supplies. The new supergreenhouse effect of the future will bring extremely hot and dry conditions to most parts of the world. Where there is rainfall and vegetation left is likely to be turned into the final fringes for growing food.

    Dr Leggett agrees with the return of the supergreenhouse effect. He said:

    'We would go back to a world that is weirdly going to be quite similar to the world in which the oil formed [in the Jurassic period] in terms of temperature, state of the oceans, and so forth. So that there's a certain irony in this whole story.' (Source: Smith, Dr Richard. Crude — The incredible journey of oil: Catalyst. 18 May 2007 (televised 24 May 2007)

    Should we destroy even those moist and green areas due to poor environmental practices, humans will face economic collapse and the extinction of the human race.

  5. Norman 1991, p.27.

  6. Connor 2001, p.13.

  7. Norman 1991, p.32.

  8. The Canberra Times 22 April 2000, p.9.

 
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