Sunday, February 12, 2017

Fullerton in Cosmic and Geologic Time

The following is from a work-in progress called The Town I Live In: a History of Fullerton.
"The lesson in all of this, if there is one, would seem to be that the many changes which have occurred in the 200-plus years since written history of this area began—which we are about to review—are minuscule when considered in the greater perspective of the last one million years on life’s landscape.” 
—Bob Ziebell, Fullerton: a Pictorial History
Any history of human life or habitation should acknowledge that, geologically speaking, we are very recent newcomers to this place.  Thus, before getting into written (human) history, I’d like to tell the story of what happened before us.  This is a story written not in books, but in rocks and stars.

Scientists today believe that the universe is about 13.8 billion years old.  For creatures with lifespans between 70 and 80 years, it’s really hard to wrap our heads around this concept of “deep time.”  It’s a humbling experience to even try.  My friend Steve Elkins, who is a filmmaker, is currently working on a documentary that took him to Switzerland where he filmed at CERN, specifically the Large Hadron Collider, aka the biggest science project in the history of humanity.  I don’t pretend to understand the various science projects they’re doing at CERN, but one of the most significant (according to Steve) involved the discovery of the Higgs boson (aka “the God Particle”), which gives insight into the conditions of the first moments after the Big Bang.  As Steve explained it to me, the “Higgs Field” was what allowed energy to slow down and form matter--what would become the stuff of stars, planets, rocks, us.

Large Hadron Collider

What caused the Big Bang?  We’re not sure, but we (well, scientists) are beginning to understand what happened afterward.  In the first episode of the recent series Cosmos (entitled “Standing Up in the Milky Way”), astrophysicist Neil deGrasse Tyson attempts to explain the immensity of cosmic time.  It goes something like this.

About 13.8 billion years ago, our entire universe emerged from a point smaller than a single atom, with the Big Bang.   


As it expanded, the universe cooled, and there was darkness for about 200 million years. Gravity was pulling together clumps of gas and heating them until the first stars burst into light. These stars coalesced into the first small galaxies.  These galaxies merged to form still larger ones, including our own Milky Way, which formed about 11 billion years ago.  


About 4.5 billion years ago, our sun was born.  Earth formed from gas and dust orbiting the newborn sun, plus collisions with cosmic asteroids.  The earth itself has quite an amazing geologic history.  A National Geographic documentary called “The Story of Earth” tells this tumultuous story in a way non-scientists (like me!) can sort of understand.  

In its early years, our planet was over 12,000 degrees celsius on the surface.  It was a toxic, inhospitable place--a boiling ball of liquid rock, an endless ocean of lava.  Then, another young planet about the size of Mars impacted earth, creating a ring of red hot dust and rock circling the earth, which eventually formed our moon.  The impact of this planet caused Earth to spin faster--for a while, a day lasted just six hours, and the moon was much closer to the Earth.  


The early Earth was pummeled by asteroids for millions of years.  Eventually, it cooled, forming a crust.  Also, pools of water began to form, which would eventually cover the Earth’s surface.  About 3.8 billion years ago, molten rock burst through the crust, forming volcanic islands, which eventually merged together to form the first continents.  

About 3.6 billion years ago, life emerged in the ocean--single-celled microscopic organisms. Some of these early microorganisms called stromatolites emitted oxygen, which slowly formed into an atmosphere.  About 1.5 billion years ago, the Earth’s crust broke into tectonic plates, which merged together to form Rodinia, the first super-continent.



750 million years ago, Rodinia began to split apart.  Volcanoes pumped carbon dioxide into the atmosphere, creating acid rain.  650 million years ago, the surface of the planet froze into something called Snowball Earth.  What released the earth from this frozen prison?  How did life survive?  Volcanoes broke the ice, filling atmosphere with carbon dioxide, trapping the sun’s heat, and the ice began to melt.  Life continued to evolve in the oceans, from multicellular life to ever more complex creatures.



About 540 million years ago, as the Earth began to warm and become more hospitable, there was the Cambrian Explosion. Increased oxgen levels allowed creatures to grow larger and develop bony skeletons, like trilobites.  Life in the oceans was blossoming from microscopic bacteria to lots of different amazing creatures, some of whom developed the first spines, an important evolutionary feature.


460 million years ago, another new supercontinent formed called Gondwana.  For much of the Earth's history, the sun's deadly radiation prevented life from forming on land.  Around this time, the ozone layer began to form, absorbing this lethal radiation, allowing the first plant life to form on land.  375 million years ago, a creature called Tiktaalik was probably the fish that emerged onto land.  After this, land-dwelling tetrapods evolved. 360 million years ago, due to increased oxygen in the atmosphere, there were giant insects: dragonflies the size of eagles called meganeura, milipedes two meters long, and scorpions the size of wolves. Eventually a creature evolved called the hylonomus, a lizard-like creature which laid its eggs on land. This was a revolution for evolution, freeing animals from living in water. As great forests rose and died, layers of dead plants slowly formed what would become coal.  250 million years ago, in the late Permian Period, there lived creatures called scutasaurs (ancestors of turtles).


Tiktaalik.

Then a great tragedy struck the Earth. Massive Siberian volcanic eruptions began what paleontologists call the Permian Extinction (or the Great Dying), the biggest mass extinction in the history of the Earth. 95 percent of all life was wiped out, due to global sulfuric ash, which suffocated life.  The atmosphere got hotter, and even vegetation died.  Methane (a powerful greenhouse gas) was released into the atmosphere--pushing up temperatures, creating mass extinction.

About 200 million years ago, the last great supercontinent called Pangea began to break apart.  Now began the Age of the Dinosaurs, who repopulated the earth--all evolved from a handful of reptiles that survived the Permean extinction. Meanwhile, tectonic plates continued to move apart, forming new oceans and continents.  During this time dead fish and plankton carpeted the ocean floor. As they were buried and heated, they formed what would become oil reserves.  The plates moved slowly, forming the Atlantic ocean. New York moved away from West Africa, Montreal from Marrakesh-- underwater volcanic activity pushed the plates apart, once again re-arranging our world into what would eventually become its current configuration.

Dinosaurs

About 65 million years ago, another tragedy struck, this time in the form of a giant asteroid from space, bigger than Mt. Everest, which scientists believe struck the earth with the force of millions of nuclear bombs. Nowhere on Earth was safe. Tsunamis and plumes of molten rock and dust engulfed the planet. The sky acted as a giant sunlamp, heating the Earth’s surface to around 275 degrees, causing many plants and animals to starve and die.  It was a split second that changed the world forever.  This was the end of the Age of Dinosaurs.



As one story ended, another began. The dinosaurs' demise gave an opportunity for another form of life to dominate the planet--mammals.  During the Age of Dinosaurs, mammals were tiny creatures, living mainly in trees, which tended to venture at night so as to avoid being eaten by dinosaurs. During the new Age of mammals, these tiny creatures evolved into a stunning array of lifeforms, eventually including us (homo sapiens).  

For most of Earth's history, the land that would become Fullerton was under the ocean. Sea creatures were were probably swimming where your house is right now.  Inside Ralph Clark Regional Park in Fullerton, there is a local Paleontology Museum, which has fossils of some of these creatures, like huge sharks, whales, and dolphins.

As the North American and Pacific plates converged about 5 million years ago, the land began to emerge from the sea, eventually creating a grassy flood plain with lakes and ponds. Over time, many interesting animals roamed the area, like giant mammoths, saber-toothed cats, a rare breed of llama, camels, bison, wolves, coyotes, ancient horses and antelope, giant sloths and tapirs.  


Me at the Paleontology Museum in Ralph Clark Park.

Rivers and streams carried sediment from erosion of the surrounding hills and mountains to fill the flood plain of this region.  During the Pleistocene Epoch, the climate of the area was cooler and the landscape was grassland, as shown by the La Habra and Los Coyotes Formations.  

The human migration into North America began about 20,000 years ago, during the last Ice Age, when there was a land bridge between Asia and North America. Eventually humans settled in this area, where they found a region rich with life. The first peoples of this area were known as the Kizh tribe, who still live in this area, mainly in and around Los Angeles.


Here I am with Ernie Salas, chief of the Kizh Tribe, and his daughter Nadine.

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