June 9 2023
https://www.visualcapitalist.com/path-of-human-evolution/

Graphic:
https://www.visualcapitalist.com/wp-content/uploads/2023/04/Human-Evolution_VF.png

The 4 Billion Year Path of Human Evolution

The story of human evolution is a fascinating
one, stretching back in an unbroken chain over
millions of years.

From the tiniest protocells to modern humans,
our species has undergone a remarkable journey
of adaptation, innovation, & survival.

In this article, we take a look at the key develop-
mental stages in the evolution of life on Earth
that led to the emergence of Homo sapiens—us!

From Protocells to People

Evolution is the result of millions of minute muta-
tions over millions of years, but the evolutionary
process that created us can bucketed into a few
key categories.

Graphic: Key Evolutionary Stages
https://www.visualcapitalist.com/wp-content/uploads/2023/04/keyevolutionarystages.png

~~~

1. Protocells & Early Microorganisms

The first life forms on Earth were simple, single-
celled microorganisms known as protocells. These
precursor cells lacked a nucleus or other membrane-
bound organelles, & they had simple genetic proteins
called RNA.

Over time, RNA complexified into the more stable
DNA. Protocells slowly developed specialized organ-
elles, becoming more complex microbes that would
eventually form eukaryotes – the complex, unicellu-
lar organisms that would birth a diverse array of life
forms, from simple sponges to complex animals.

~~~

2. The First Animals

Dickinsonia is the earliest example of an animal we
know of. Though it was a simple, flat creature that
lacked a mouth or digestive system, it symbolizes
the first multicellular organism of substantial com-
plexity.

Over time, the first sophisticated organ systems be-
gan to arise. Bilateral symmetry emerged, as well as
early versions of the nervous & circulatory systems.
Simple eyes, called eyespots, also appeared around
the time that spinal cords & vertebrate creatures be-
gan to emerge.

~~~

3. Fish & Tetrapods

One of the most significant developments in the evo-
lution of life was the transition from marine to terres-
trial environments.

Up until 500 million years ago, all life was sequestered
in the sea. Fish were the first vertebrates & introduced
additional organs like stomachs, spleens, & body com-
ponents like scales, teeth, blood, & more. Bony fish ...

.... arose, & over time their development brought about
sophisticated changes to the skeletal system, even-
tually producing “proto-limbs” that would enable organ-
isms to walk on land.

Researchers are still unsure which specific organism
might have first crawled on land, but candidates share
these pre-limb characteristics. Tiktaalik is one popular
candidate because it had specialized bones that sug-
gest it could support its own weight while moving out
of shallow waters.

These creatures eventually became the tetrapods
(“four-footed”), & they had features like four-legs, a
backbone, & lungs which could absorb oxygen from
air. All the amphibians, reptiles, birds, & mammals
that followed are descendants of the original tetra-
pods.

~~~

4. The First Mammals

Around 200 million years ago, the first mammals
emerged. These early mammals were small, shrew-
like creatures that lived alongside the dinosaurs.
Over time, however, mammals evolved hair, special-
ized teeth, sweat glands to regulate body tempera-
ture, & a more efficient circulatory system.

Mammals also brought about features like nocturn-
ality, mammary glands, external genitalia, & a variety
of other features that distinguished them from other
living species at the time, like birds or reptiles.

~~~

5. The Great Apes & First Homo Species

Around 7 million years ago, the first great apes emerged
in Africa. These apes, such as orangutans, gorillas, &
chimpanzees, were highly intelligent & social creatures
that lived in complex communities. Over time, one line-
age of apes would give rise to the first members of the
genus Homo, which includes our own species.

The main developmental changes during this time were
the full-time bipedalism of apes, increasing brain size, &
advanced bone development that enabled dexterity for
tool construction & hunting. Inventions like fire & clothing
arose early in the Homo genus, & eventually complex lan-
guage, hair loss, & dramatic facial changes would evolve.

Researchers struggle with resolving the exact progres-
sion of the Homo species. Many Homo species existed
at the same time, & since many fossil records overlap,
resolving which ones came first is an area of intense
focus.

~~~

The Future of Human Evolution

As humans continue to evolve, we can expect to see sig-
nificant changes in our physical & cognitive abilities over
the next 10,000 years.

With the rise of technology & the increasing interconnect-
edness of the world, we may see a shift towards a more
globalized & homogeneous human population, with less
genetic diversity.

This has been described as “The Great Averaging”, where
genetic diversity minimizes & we start to become more
alike.

Other theories suggest that we might develop features
like a taller, lighter build, with smaller brains [smaller
brains? I hadn't heard that hypothesized before & not
aware of why/what their basing that prognostication
on] & a less aggressive personality.

However, as with all evolution, these changes will be
shaped by a complex interplay of genetic, environmen-
tal, & cultural factors.

It is impossible to predict exactly how humans will
evolve over the next 10,000 years, but one thing is cer-
tain: the future of human evolution will be shaped by
the choices we make today.

[The most dramatic alteration of human evolution,
that brought about by mass extinction events (refer
to the following for details on 5 mass extinction
events in the last 445 million years), difficult to pre-
dict how the next mass extinction event would im-
pact future human evolution:
https://en.wikipedia.org/wiki/Extinction_event ]

Note: This is a complex topic with new research being
published all the time. We’ll continue to dynamically
update this graphic to reflect the most recent under-
standing of evolution.

[One aspect of our evolution omitted (neglectfully so
by the writers of this article), the manner in which arti-
ficial intelligence & artificially induced DNA alterations
may dramatically alter what will become a hybridized
form of human/artificial intelligence that one can only
guess about right now, the future not yet written & dif-
ficult if not impossible to foresee]

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