Could Something as Pedestrian as the Mitochondria Unlock the Mystery of the Great Silence?

Erasmo Acosta
Apr 8 · 7 min read
Image Credit: Erasmo Acosta ©2009 All rights reserved

I dozed my way through twelfth-grade biology dreaming about my next-door neighbor. What little I crammed about DNA, RNA, and ATP for my finals was promptly discarded in the junkyard of my adolescent mind.

Decades later, a burning obsession with the Fermi paradox — a hint that we might be the only civilization in the galaxy — forced me to dust off my otherwise forgotten biology lessons. Where are the aliens? Hundreds of explanations have been proposed for their apparent absence in our cosmic neighborhood, many grounded on science, others on pure mysticism, but Fermi’s question remains unanswered after 70 years of debate.

Rewinding into the history of life on Earth, we find some pretty astounding accidents. No, not the dinosaur-killer asteroid, although it was the perfect size and stroke at the right time. In 4.5 billion years, life had many miraculous close-calls before reaching consciousness and, even after then, we survived self-annihilation a few times.

“In 1974, astronomer Michael Hart published the first paper building on Fermi’s argument. Hart proposed that if an alien civilization had evolved in our galaxy, it would have developed interstellar travel and colonized its neighboring stars. These colonies would, in turn, launch colonizing expeditions to their neighboring stars, and so on, occupying the entire Milky Way within two million years.” -Excerpt from my novel K3+

Clownfish and sea anemone, a well-known symbiotic relationship. Image Credit: wallpaperuse.com

The ultimate symbiosis

Our technologically advanced civilization was built by tool-manipulating self-aware multicellular beings also capable of interpreting the physical laws of the universe. Multicellular life on Earth is based on eukaryotic cells.

It’s the scientific consensus that a primordial eukaryote emerged 1.5 billion years ago when a less complex cell tried to ingest an bacterium but was unable to digest it. The stalemate turned into a symbiotic relationship in which the bacterium became the power supply to the host cell, which provided a safe environment for it to thrive in return. Today we refer to the powerhouse of the cell as the Mitochondria.

This perfect relationship allowed both organisms to reproduce together and successfully spread throughout the planet, eventually becoming the prevalent type of cell of multicellular life on our planet. Scientists also believe that this event occurred only once in Earth’s history, based on mitochondrial genes common to all species.

Image by Erasmo Acosta. Credit for Earth’s icon and City Skyline: freesvg.org

We are capable of building a Dyson swarm around the sun within a 1,000 years and do the same with all viable stars in our galaxy in a pinch of cosmic time.

A miracle like no other

The University of Potsdam recently estimated the total number of single-celled organisms in our oceans to be 2.9 x 10²⁹, or about 0.3 nonillions if we round up. We cannot determine the actual number on early Earth but can use this number as a baseline.

Now imagine that many single-celled organisms eating each other for over 2.5 billion years until the right pair, which could form a symbiotic relationship, came into contact. It’s possible that many almost-right pairs got halfway there, but only one lucky couple was finally successful.

Unlike other evolutionary adaptations, there is no selective pressure that would place these two compatible cells — among 0.3 nonillion others on the planet — close enough to each other for such a miracle to occur. It was a pure chance event after eons of evolution that changed the course of life on Earth. What we are today, all of our accomplishments, wouldn’t have been possible without it.

After another 900 million years of continuous evolution, eukaryotes developed the right mechanisms to organize into the first multicellular life on the planet — sponges or perhaps something simpler yet to be discovered.

We also know that multicellular life evolved independently over 20 times during this period. From it, we can infer that this type of cell must have been well endowed to cooperate and bond with each other and that the jump to multicellular life was far easier to achieve than the evolution of the mitochondria.

Image Credit: NASA ESA, Z. Levy (STScI)

If a person is walking home from a park half a mile away and doesn’t arrive within the hour, something out of the ordinary happened. That is the essence of the Fermi paradox.

Winners of the cosmic lottery

Most stars in our galaxy are red dwarfs invisible to the naked eye. It’s been suggested that worlds orbiting their habitable zones might not have strong enough magnetic fields to protect against the fierce radiation emanating from these flaring stars — which produce hundreds of times the amount of radiation of the sun.

Only 2.5 percent of stars in the Milky Way are yellow dwarfs like our sun, and recent studies indicate it appears exceptionally tame compared to others of its kind. Furthermore, yellow dwarfs are short-lived. Within 5 billion years, the sun will turn into a red giant engulfing the inner solar system. Even worse, a 10 percent increase in luminosity within the next 500 million years will be catastrophic for life on Earth.

If multicellular life can only thrive on planets around stars like our own after 4 billion years of evolution and we needed cosmic help to get evolutionary dead-ends (like the dinosaurs) out of the way, it dramatically reduces the chances of life growing into a technologically advanced civilization — before the host star cooks their planet to embers.

Depiction of an alien civilization building Dyson swarms in their home galaxy. Image Credit: Hubble Heritage Team, modified by Adriana Ayala

We know that the inner solar system contains virtually unlimited resources which we could use to build space-bound colonies.

Fermi’s clever argument

If a person is walking home from a park half a mile away and doesn’t arrive within the hour, something out of the ordinary happened. That is the essence of the Fermi paradox. Given the age of the Milky Way, it’s been thousands of times long enough for a civilization at our current technological level to colonize it. Even without faster-than-light travel, we can accomplish this task within two million years — a blink of an eye in the scale of the universe.

We are capable of building a Dyson swarm around the sun within 1,000 years and do the same with all viable stars in our galaxy in a pinch of cosmic time. Therefore, an alien civilization predating us by just a few million years would have done it already. The night sky would look very different because a Dyson swarm captures all visible light emanating from a star.

The detection threshold for such a civilization with our current telescopes is up to a billion light-years radius. The alien expansion wave will appear like a dark cloud expanding away from their home star. Nevertheless, all we see in our cosmic neighborhood is raw wilderness.

Each tiny bar represents a single rotating habitat capable of housing millions. Image Credit: Katie Lane (Full distribution rights reserved by Erasmo Acosta)

“If we are bound by the laws of thermodynamics, Dyson swarms are inevitable! A growing civilization that has depleted its planetary resources and has a desperate need of room to grow will have no other option than to build rotating habitats around their home star to avoid choking to death! And once they’ve harnessed their home star, spreading across the galaxy will only require persistence and a pinch of cosmic time!”-Excerpt from my novel K3+

Opening the door to the stars

While we continue fighting and competing against each other for the sake of power, often at the brink of self-annihilation, the cosmos awaits with answers to all our terrestrial predicaments.

Most of the technologies we need to colonize space are ready, but we lack the wisdom to get past our human biases and preconceptions. We know that the inner solar system contains virtually unlimited resources which we could use to build space-bound colonies. We can house more people in a Dyson swarm of rotating habitats around the sun than on all habitable planets in our galaxy.

The miracle of the mitochondria, a random encounter of two microorganisms lost to the eons of time, is nothing less than humbling. Adding other evolutionary close calls from our past, it hints at how lucky we’ve been and how carefully we must safeguard the legacy of our species to avoid destroying ourselves, treat our planet with respect, and ensure the human species spread throughout the cosmos. The coming decades will determine how we invest our cosmic lottery winnings.

What does the future of humanity hold?

Based on the Fermi paradox, my dystopian novel K3+ is a roadmap to the future based on today’s technology. How do we survive our current dystopia to save Earth and build a post-scarcity spacefaring civilization?

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Erasmo Acosta

Written by

Casualty of Corporate America | Sci-fi writer | Science Junkie | Learn about my dystopian novel K3+ (now on sale) at https://erasmixbooks.blogspot.com

Predict

Predict

where the future is written

Erasmo Acosta

Written by

Casualty of Corporate America | Sci-fi writer | Science Junkie | Learn about my dystopian novel K3+ (now on sale) at https://erasmixbooks.blogspot.com

Predict

Predict

where the future is written

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