Mars and the Fragility of Life

For much of human history, Mars has occupied a unique place in our imagination. It is close enough to feel familiar, yet alien enough to provoke speculation. For a long time, the question was framed simply: was there ever life on Mars?

Today, a more interesting question presents itself:

If Mars could support life, why did it not persist, and what does that tell us about how rare intelligence might be in the universe?

Listen as a Podcast Discussion or watch as a Storyboard Video

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Mars was not always the world we see today

Billions of years ago, Mars was very different from the cold, dry planet we observe now.

Multiple lines of evidence show that early Mars likely had:

• liquid water on its surface
• rivers, lakes, and possibly shallow seas
• a thicker atmosphere
• internal heat and geological activity

These are not speculative claims. They are supported by orbital imaging, mineral analysis, and rover data showing ancient river valleys and water-altered rocks.

In other words, Mars once met many of the basic requirements for life.

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Life does not need perfection, it needs opportunity

On Earth, life appeared remarkably early. As soon as conditions allowed liquid water and chemical stability, biology emerged.

This suggests an important principle:

Life may not be rare. Stability is.

If life can arise quickly when conditions permit, then early Mars had a genuine opportunity. Even a few hundred million years, a short window in cosmic terms, may have been enough for microbial life to appear.

Mars, then, may not represent a failure of life, but a failure of longevity.

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The importance of planetary “margin”

What ultimately separates Earth and Mars is not a single factor, but margin, how much room a planet has to absorb shocks and recover.

Mars faced several disadvantages:

Low gravity

Mars is much smaller than Earth. Its weaker gravity made it harder to retain a thick atmosphere over long timescales.

Loss of magnetic field

Early Mars likely had a molten iron core and a magnetic field. As the planet cooled, that dynamo shut down. Without magnetic shielding, the solar wind was free to erode the atmosphere.

Rapid cooling

Smaller planets lose internal heat faster. As Mars cooled, volcanic activity diminished, removing a key mechanism for recycling gases and stabilising climate.

None of these alone doom a planet. Together, they create fragility.

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A narrow window can still host life

This is the critical point that often gets missed.

Mars did not need billions of stable years to host life, only enough time for chemistry to cross the threshold into biology.

If life did arise on Mars, it likely remained:

• microbial
• simple
• localised

When conditions worsened, that life would not have had time to adapt, diversify, or reshape the planet as life did on Earth.

Mars may have been alive, briefly.

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Why intelligence never followed

Here is where discussions about “intelligent life on Mars” often go wrong.

Intelligence is not a natural endpoint of evolution. It is an accident of surplus.

To evolve technological intelligence, a planet needs:

• long-term environmental stability
• abundant energy over geological time
• ecological complexity
• time to experiment without frequent resets

Earth had all of these, and even then it took billions of years.

Mars almost certainly did not.

If a technological civilisation had ever arisen there, it would have left unmistakable evidence: orbital debris, artificial materials, long-lived structures. We see none.

That absence is not mysterious. It is expected.

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Mars as a warning, not a disappointment

Mars teaches us something uncomfortable but important:

Life may be easy to start, but hard to keep going.

The universe may produce many worlds where life flickers briefly, only to vanish before complexity can take hold. Intelligence, technology, and long-lived civilisations may be the rare exceptions that require extraordinary planetary luck.

Mars is not a failed Earth.
It is a reminder of how thin the margin really is.

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Earth did not just get lucky, it had redundancy

Earth’s success is not due to a single perfect parameter. It is due to overlapping safeguards:

• strong gravity
• long-lived magnetic field
• plate tectonics
• active carbon cycling
• vast oceans

When one system falters, another compensates.

Mars had fewer backups.

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The broader implication

If Mars represents a common outcome, brief habitability followed by decline, then the universe may be full of worlds that almost made it.

Life may be widespread.
Intelligence may be fleeting.
Technology may be rarer still.

This reframes the search for life beyond Earth. The question is not “Does life exist elsewhere?” but:

How often does a planet stay kind long enough for life to become aware of itself?

Mars suggests: not often.

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Closing reflection

Mars is not silent because nothing ever happened there. It is silent because whatever may have begun did not last.

In that sense, Mars is not a story about absence, it is a story about timing.

And it reminds us that Earth’s greatest gift may not be its position, its chemistry, or even its biology, but the simple fact that it stayed stable long enough for life to wonder where it came from.

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