Ospot Water Animals

   
When Dalman plant cells first appeared in Letjenje's oceans 2 billion years ago, there were few animal life forms.  As plant cells produced oxygen, and this element's amounts built in the atmosphere, biotic (oxygen using) animal cells could finally form.  No one is yet sure how the first animal cells first formed in the ocean - perhaps it was from a plant cell with no chloroplasts- but the fossil record shows Ospotum existing 1.5 billion years ago in Letjenje's oceans.  This organism, shown below, lived about  
10 feet under the water as UV radiation was still too strong.  Ospotum consisted of a nucleus with DNA (located on the chromosomes), vacuoles for storing food and waste products,  a cell membrane which regulated the food entering the cell and the waste exiting it, and mitochondria which converted food into energy. 

Ospotum  cell


Ospotum
existed in the open sea, "eating" other unicellular plants and animals.  It "ate" by surrounding and enveloping its prey, then the cell membrane would open to let the food enter, immediately closing again.  The food was stored in a vacuole until the enzymes in the mitochondria would convert it into energy to fuel the cell's processes.  Ospotum reproduced by simple cell division.

Ubella (note the mouth-like opening at right)


Ospotum's method of encircling food was very slow, and in the constantly moving waters of the ocean, was not terribly effective.  Quite often, the organism would be moved away from Ospotum by an ocean swell.  Ospotum evolved a mouth- like structure about 950 million years ago.  The new organism, Ubella, was able to hold food in this "mouth" while the rest of the cell would surround it and then take it into the cytoplasm through a brief  and small opening in the cell membrane.
Ubella was a much better predator than its predecessor, Ospotum, but was still very slow. While it continued to consume small plants and some animals, Ubella was also not able to keep up with other animals which were evolving fins, spikes, and other adaptations of defense and locomotion.  Further, as Letjenje's atmosphere evolved, storms began to occur, washing Ubella up onto rocky shores, newly forming coral reefs, and into kelp forests, becoming thick with vegetation. 
Around 600 million years ago, through mitosis and changing environmental conditions, Ubella mutated into 3 different species: Pin Cushion, found in coral reefs, Dempsey, living in kelp forests, and Finky, residing along the shallow, rocky ocean shore.
The first adaptation of Ubella was when it evolved into Dempsey, a small fish living among the emerging kelp- like forests.  Dempsey had a real mouth and digestive system, rather than Ubella's mouth like structure that served to hold food, rather than ingest it.  Further, it developed eyes

Dempsey

so that it could see both its prey and predators.  It had a dorsal fin to help it glide through the water faster, as well as pectoral (front) fins which allowed it greater maneuverability.  Its tail moved back and forth to propel it, allowing it great success when chased or being chased.  It breathed through gills and was about 2 inches long.  It ate the plants of the kelp forest and hid in its leaves.

Horned Dempsey
As the fish around Dempsey evolved into larger and more aggressive forms, Dempsey further adapted around 300 million years ago into Horned Dempsey. The horn, a spike actually, that grows from the tip of the nose and along the spine, helps to deter predators.  Scientists believe that the "horn" was the result of a mutation that proved to be a beneficial adaptive structure.
Horned Dempsey quickly replaced the unarmed Dempsey by about 250 million years ago and can still be found in Letjenje's kelp- like forests.    
Many Ubella organisms found themselves washed into warm, shallow equatorial waters.  Here, some species of coral had began to form, and Ubella latched itself onto one of these structures.  Rather than pursuing its food, the new organism, Pin Cushion, waited for its food to float by. Like Horned Dempsey,
Pin Cushion developed spikes to protect it from predators.  It also has a small mouth opening in the fleshy part of its body where water can be taken in and small microscopic animals  filtered out and used for food.  Being attached to the coral - like reef is advantageous as Pin Cushion cannot be swept away by the tide or storm

 

 

 

 

Pin Cushion

driven waves.  The hard, sharp exoskeleton gives the animal, ranging in size up to 6 inches in diameter, excellent protection that has ensured the species' survival until present times.
Not all Ubella organisms found themselves washed into shallow, equatorial waters.  Many were washed into cooler, rocky shallows around Letjenje's continents.  There, they had to adapt to fluctuating water depths, tidal surges, sharp rocks, and a huge variety of life forms evolving.  Scientists believe that Ubella drifted into the sand and mud at the bottom of these waters, and was able to adapt to feeding off of decomposing organic matter.  Like Pin Cushion, this new species called Finky, was able to filter its food out of the water it took in through its mouth.  However, Finky was very vulnerable to other life

Finky

forms and evolved a hard exoskeleton.  Since these waters were filled with a diversity of life, Finky flourished.  In stormy years when the plants that clung to rocks were drowned or washed out to sea, intense competition resulted over the limited food source.  Since Finky had to battle against members of its own species as well as other bottom feeders, two arms with claws attached evolved.  These arms
are able to regenerate themselves if lost in battle which makes Finky one of the ocean's most enduing warriors.  It also has three pairs of legs that enable it to walk along the ocean bottom as well as two antennae to help detect food or enemies.  Finky's grayish color helps it to blend into the rocks and sand, and its large eyes (which don't see very well) scare off potential predators as they think that they have been seen by Finky and won't attack.
 
Below is a family tree of the Ospot progeny.  All but Ospot reproduce(d) by mitosis to allow greater variability and adaptation to Letjenje's changing conditions:

 

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page by Jennifer Lewis