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14.3
The battle for survival and the environment
 
 

It is generally assumed by the conditions in which we live, that the conditions on planet Earth have remained similar. We make this daily assumption in the way we dress, even though we know through research and experience that the conditions for life on Earth change and have been dramatically different in the past.

  
  Even so, our understanding of the extremities of conditions, is hard to fathom, unless brought back to life thanks to digital animations such as more recent digital dinosaur movies.  
14.3.1 The dramatic periods of temperature and density  
  To the human being, it is inconceivable that we could possibly live in an environment of 35 degrees Celsius 90 percent humidity and incredible pressures of 4G and 6G's. We simple would not be able to breath, we would not have enough strength to survive.  
  Even on a hot day of 35 degrees Celsius and above, humans find the conditions difficult. The same applies for conditions of extreme col, such as constantly under 10 degrees Celsius  
  Yet there have been many times on planet Earth, when conditions for life we at these extremes. And if life had not found ways to adapt and survive, then no life would presently exist on this planet.  
14.3.2 Understanding the environment, to understand the adaptions  
  One of the intriguing complexities of viewing life is the sheer diversity of life itself. Different animals, different plants, different features, different foods, different natural habitats and ideal climactic conditions.  
  Because of this complexity it is often hard to imagine how such a complex array of life could have evolved from such simple and similar life as mono cellular and mono neural organisms such as bacteria, algae and fungi.  
  So in recognizing key periods of extreme conditions (in our opinion), we might better understand why life adapted and therefore certain types of cellular life evolved.  
  We will discuss this relationship between conditions on Earth and life on Earth in more detail in chapter 17 (LIFE ON EARTH). For the moment, let us look at some of the challenges that life has had to overcome.  
14.3.3 Heavy, hot and wet life on Earth  
  Life has at times had to cope and adapt with conditions in the past when the rotation of the Earth was faster, gravity was significantly higher, temperatures were hotter and humid.  
  Under these pressure cooker conditions, hard shelled- soft bodied creatures could survive up to a point. But without superior methods of structuring, could not advance any further.  
  In these hot, heavy and wet conditions, ideal life thrives whereby an organism, expands in size, using an internally protected neural system, surrounded by soft tissue and then protected by thick, elastic water proof type skin. Such life would have the internal muscle strength to move in spite of the incredible pressures, sufficient body mass area to radiate excess heat and protective skin to avoid osmosis (internal drowning because of too many water molecules).  
  To survive and thrive in these conditions, a new kind of strategy needed to emerge, beyond the hard external body, soft body concept. The internal cytoskeleton had to fuse into self contained, strong blocks capable of withstanding incredible pressures. A new kind of structural cell- or bone cell had to emerge.  
  As we will see, this is exactly what emerged on planet Earth during extended periods of high density, het and humidity with the first vertebrates (back boned animals), the prototype reptiles.  
14.3.4 Cold, windy dry life on Earth  
  Just as there has been periods of tremendous pressure, het and humidity, the Earth has gone through periods of extreme col, dry and lower gravity.  
  In these conditions, large lifeforms as per those ideally suited for het, wet and heavy conditions, would have perished. A completely reverse set of conditions would have existed. Instead, lifeforms with small to medium body masses, thick aerated skin, with hair and internal heating would have thrived.  
  As we will see, this is exactly what happened with the development of proto-marsupials and birds.  
     
 
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