ORIGIN OF LIFE

 

Solar-U4-NGC-1333-IRAS-4B

BIRTH OF A SOLAR SYSTEM

I’m sure you’ve all heard of the biblical stories of how God created the heavens and Earth, and I do believe the need for faith myself in the scheme of things.  We’ve heard the ancient alien explanation, which leads me to ask the question,”If they created us, who created them?”  The truth, as we have seen through science and religion, is probably somewhere in the middle.  We have no proof God created the universe, but we also have no proof that he did not either.  But we have a pretty good idea of how we all got here, and whether it is spiritual or not, it is nothing less than miraculous.

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About 4.5 billion years ago, there was a gravitational collapse of part of a giant molecular cloud of hot gasses.   The mass collapsed to the center, forming a hot ball of gas, which we now know as the sun.  As the mass began to spin, it exploded into a supernova.   The leftover debris became the planets, moons, and asteroids.  It’s believed that the solar system was much more crowded in those days,  with the kuiper belt much closer, as well as planetary bodies.  We used to believe the process took at least a billion years, but recently the Hubble Space Telescope has found a system less than a million years old that has begun this process.

planetImpactBarringer_Crater_aerial_photo_by_USGS

As the planets collided, they formed larger planets.  Those closer to the sun became rocky planets, and those beyond the frost barrier became gas giants.  Our planet is believed to have collided with another to form the Earth.  Part of ours broke free to form the moon, which is now locked in orbit, but will eventually begin to drift farther from us through time.  As the earth began to spin very fast, it heated, and became a hellish world, the kind of world where life couldn’t exist-yet.  It was bombarded by objects such as asteroids, comets and meteorites, there was no oxygen due to a toxic atmosphere, and extreme radiation.  As the earth began to cool and slow down, the liquid metallic elements began to solidify.  The heavier materials sank to the middle, forming a solid iron core, which gave it its magnetic field.  This magnetic field began to deflect radiation, and an atmosphere slowly began to form.  the lighter materials became the outer core, mantle and crust.  This became the stepping stone for the creation of life.

earth_formed

How could a totally poisonous world become one that could create life?  We will find out that tomorrow.  Until then, here are today’s links:

http://en.wikipedia.org/wiki/Formation_and_evolution_of_the_Solar_System

http://www.extremetech.com/extreme/193710-birth-of-a-solar-system-the-first-ever-high-resolution-image-of-planet-formation

http://www.extremetech.com/extreme/193710-birth-of-a-solar-system-the-first-ever-high-resolution-image-of-planet-formation

https://www.bighistoryproject.com/chapters/2

 

Earth_formation

A NEW PLANET IS BORN

After the planetary collision and heavy bombardment period, known as Hadean Eon, the earth began to cool down.  Several comets and asteroids brought massive amounts of frozen water to our planet, and as sulfuric and volcanic gases spewed into the atmosphere, it created a greenhouse effect. There were far more comets in the inner solar system than there is now.  Hot rains poured upon the land and created shallow oceans, and the atmosphere still lacked oxygen and an ozone layer.  This period was known as the Archean Eon.

Positions_of_ancient_continents,_550_million_years_ago

Scientists believe that the planet had three separate atmospheres in its history.  The first atmosphere was mostly light elements such as hydrogen and helium, the second atmosphere was rich in greenhouse gases, such as carbon monoxide, methane, and sulfur, and the third atmosphere was rich in oxygen.

three

Although they have replicated amino acids and simple organic compounds, scientists have yet to create the actual building blocks to create life.  It is still not known how life emerged from non-living organisms.  It is believed RNA is possible for the earliest microbial life, through the process of self replication, development of membranes to enter and exit food, and the metabolism to feed and repair itself.  RNA didn’t allow cells to create species due to mutations of the cellular organisms.  DNA proved to be more stable and detrimental to the origin of life.

 

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During the Proterozoic Eon, about 2.5 billion to 542 million years ago, land masses formed into continents, and the atmosphere became rich in oxygen.  This period saw two ice ages, which led to the Avalon explosion, which paved the way for primitive plants  that produced photosynthesis.  Life on Earth probably wouldn’t have existed at that point if it weren’t for greenhouse gases from volcanic activity that reheated the earth from its frozen state.  Tomorrow, we will look at what type of primitive life evolved from the newly formed oceans.  Until then, here are the links of the day:

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http://en.wikipedia.org/wiki/History_of_the_Earth

http://www.udayton.edu/~INSS/ThemeEvol/evoltimelineMED/secondchunk.htm

http://rainbow.ldeo.columbia.edu/courses/v1001/7.html

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LIFE FINDS A WAY

After the two major ice ages, which made a giant ice ball out of our planet, the Earth became warmer, partly due to the increasing power of the sun, and partly to volcanic activity.  Oxygen flowed throughout the atmosphere, as small algae-like organisms increased the process of photosynthesis.  As we have seen, single celled organisms became complex cells with organelles(Eukaryotes) about 1.85 billion years ago.  About 1.7 billion years ago, multicellular organisms began to appear, and about 555 million years ago, bilateria animals began to appear as well.

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During the Denovian period, or the age of fish, sea creatures thrived in the oceans, and were primitive fish-like creatures, as well as segmented worms, fronds, discs, trilobites, brachiopods, lung fish, and ceolocanths.  This sea creatures seem strange and alien to us because there are only a few of these alive today, such as lung fish, ceolocanths, and sturgeon.  During this period, the earliest land plants began to emerge, about 450 million years ago, and trees with roots began to emerge as well.  The first land insects evolved about 358.9 million years ago, and are still the most resilient and abundant species on earth, outnumbering us a million to one.

Dunkleosteus_BWdevonian-dunkleosis

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It is still not known what led to Denovian extinction, when 99% of life on Earth vanished.  Amphibians were taking hold of the land then, the survivors of the shark-like ancestors.  It is believed that there was a possible mass extinction of the oceans, due to a depletion of oxygen, which can still happen with invading forms of algae today.  It may be that the plant life in the ocean was just too abundant for the variety of species.  There were two continents at the time;Gondwanda, which included South America, Africa, Asia,  South America, and Antartica, and Euramerica, which included North America, Europe, and the Arctic.

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But you may ask, if 99% of life was eliminated, how did we get here?  The answer is simple, life found a way.  Fish that found themselves on land adapted lungs and limbs, like the lung fish.  They later became amphibians, which led to the next evolution of Earth-life on land, and tomorrow’s topic.  Until then, here are today’s links:

http://en.wikipedia.org/wiki/Ediacaran

http://museumvictoria.com.au/melbournemuseum/discoverycentre/600-million-years/timeline/ediacaran/

http://en.wikipedia.org/wiki/Devonian

http://www.fossils-facts-and-finds.com/devonian_period.html

IchthyostegaliaClack05

THE  AGE OF AMPHIBIANS

About 350 millions years ago, at the end of the Denovian period, fish crawled onto to land, and evolved into the first amphibians.  They weren’t like the amphibians we know today; they were much larger, and possessed gills at first, had huge heads, and sometimes had eight digits on each foot.  There were several common species, including Eryops, Ichthyostegas, and Acanthastegas.  Most died out by the Mesozoic Era, after reptiles started to become the dominant species, but some survived into the group of amphibians we know today called Lissamphibia.

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Amphibians differ from reptiles and other vertebrates in three distinct ways:  1. Newborns possess gills, and grow lungs as they reach adulthood.  2.  They lay eggs in the water as opposed to land.  3.  Their skin is slimy to allow additional oxygen for respiration.  Early amphibians broke off into two branches- Lepospondyls, which are amphibian-like, and temnospondyls, which are more reptilian-like, and learned to adapt to the land.

 

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Amphibians are mostly carnivores, eating small insects and fish.  In my book,  Dimension Lapse, the lingworts are amphibian-like creatures that eat fish, but are also herbivores as well.  This is because this is the way they evolved on Ventros, and as they became animals capable of speech and thought, their belief system would not allow them to eat meat, so they became similar to the early dinosaurs, and even became bipedal.  This may sound crazy and outlandish, but somewhere in the universe, this could be a possible route of evolution.  Like I have said earlier in the series, matter on other planets does not have evolve the same way as here, and probably doesn’t.  We do know that it is entirely possible for something to be totally alien in nature; we have already seen it in the depth of our oceans.

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Monday, we will be starting a special series, and the next step of evolution and the most dominant species on the planet to date-the dinosaurs.  Until then, here are today’s links:

http://www.edgeofexistence.org/amphibian_conservation/ancient_amphibians.php

http://dinosaurs.about.com/od/otherprehistoriclife/a/prehistoric-amphibians.htm

https://www.boundless.com/biology/textbooks/boundless-biology-textbook/vertebrates-29/amphibians-173/characteristics-and-evolution-of-amphibians-668-11889/

 

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SCIENCE FICTION AND SCIENCE REALITY

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