Abiogenesis
Abiogenesis
Djambe?
Why is there life on Earth?
Extreme heat
billions of years ago
has shaped our world.
Earth was plagued by massive
volcanic eruptions.
Meteorites constantly pounded the surface,
causing cataclysmic geological
and chemical transformations.
This ungrateful environment was crucial
to the formation of life.
Evidence of this can be found all around the world
like here.
The Tswaing crater.
Some 220,000 years ago,
this crater was formed by a gigantic impact
the meteorite was traveling
at 25 kilometers per second
when it smashed into the ground.
It’s a real hike.
There are very distinctive
marks here in the stone.
How the granite was deformed
by the impact of the meteorite.
It was just 50 meters wide,
but created this 1.6 kilometer big crater
In the words of your own grandfather.
“The more you see, the more you understand.”
Djambe?
Tell me more about the origins of life.
Life results from chemistry,
it emerged out of non-living molecules,
we are made of the same atoms
born in the stars
billions of years ago.
The right ingredients in the right amounts
combined under the right conditions.
Science says life started
in a primordial soup,
a kind of a chemical melting pot
where for yet unknown reasons,
organic molecules formed.
Every creature is made of cells.
Inside these cells is
a nucleus containing
chromosomes that hold the DNA,
which in turn is made of genes.
Genes are life’s information carriers.
They provide your biological system
with the proper information to follow
as you grow and evolve.
Your DNA tells a story.
It’s like a logbook of your ancestry.
It is how nature carries information
through space and time.
In my case, it is the only way to figure out
where I really come from.
See my mother, my father
they come from the islands of Cabo Verde,
a tiny paradise nation
of off the coast of Senegal.
But I was born in Europe,
and I always say the only difference
between me
and all other Africans
is that I immigrated before being born.
Before the Portuguese
stumbled upon this place,
these ten islands
were practically uninhabited.
Then they brought in slaves
from all across the continent.
People started flocking in.
Jews exiled from Europe.
Explorers, exploiters,
curious people, merchants.
My uncle used to say
Cape Verdeans are the
children of the Atlantic Ocean.
Descendants of slave candidates
that did not quite make it
to the other side of the pond.
As a consequence in my family,
there’s all this hearsay and stories.
Examples of good and less good encounters.
It is quite difficult
to draw a mildly accurate family tree
when all you have
is the surname of a slave master.
Right?
I have this DNA test kit.
I carry it with me everywhere I go.
If I take a sample of my saliva
and send it to the lab, they will tell me
everything I need to know.
It’s like a portal to my ancestors.
Now all I need is the courage to take it.
Another six kilometers to go.
I have to make it back before sunset.
Talking about survival of the fittest.
For life,
threat is lurking everywhere.
We are surrounded by constant danger.
Predators,
parasites,
toxins,
changes in climate
and even animals of the same species.
Eat or get eaten.
Each individual be it plants, animals
or fungi is subjected
to natural selection.
Diversity is crucial
and evolution is life’s
constant adaptation to the environment.
Our ancestors saw life as a
self-balancing act in the interest of all,
guaranteeing the survival of life itself
One species, though,
is threatening
the sophisticated equilibrium.
This species is us.
We are so powerful we became a threat to
every other species on Earth.
Nature has a
surprising way to protect itself
from unexpected
and sometimes unnatural changes
to the cycle
of life.
Gorongosa National Park,
Mozambique
During the 15 year war,
90% of all elephants
fell victim to poachers.
They were ruthlessly killed for their Ivory,
a significant source of revenue
to finance arms.
Under normal circumstances,
a small number of 2 to 4%
of all female
elephants are born without tusks.
They have lost their defense
and natural means to gather foot,
but humans have no interest
in killing them.
By the end of the war,
half of the surviving
elephant cows were tusks-less.
A generation later,
most newborns are the offspring
of these same tusk-less
mothers.
Their daughters, the new generation,
represent a third of all elephant cows.
And just like their mothers,
they have no tusks.
The rare genetic trait
that causes elephants to be born
without tusks
gave them a biological advantage.
Evolution increased
the number of elephants without tusks
and with it, the chances of survival
for an entire species.
Unfortunately,
the process is not enough to protect this
colossal and marvelous
mammal from human caused extinction.
In an environment where
tusks can mean death by poaching,
having such a simple gene
disabled in their DNA
can decide about the survival
of an entire species.
The theories of evolution
did not start with Darwin, among others,
Ibn Khaldun
had already made the same observation
and eternalized
his ideas in his writings.
Here in Africa.
Humans are a result of this
same process of evolution,
and it all started here in Africa.
Every human being that ever lived
can be traced back
to this continent.
Africa is where the human journey begins,
and if we want to understand humanity,
we have to know its cradle.
An African proverb says:
To know where you are going,
look first at where you come from.
On her numerous voyages
Johari learned that archeology
plays an essential role
in the quest to understand Africa.