Did The Human Genus Occur By Chance?

It’s long been assumed that the human genus originated during a significant climate change event in Africa. According to this hypothesis an ice age occurred between 2.8 and 2.5 million years ago which coincided with a pulse or cluster of diverse new species, including Homo. These pulses may be seen in the African fossil records.

It’s a theory partly made popular because of its grand theater. It highlights a dramatic story of humans having evolved into a sophisticated species with huge brains under extreme pressure. It sounds heroic to become a clever enough survival in a few hundred thousand years after the onset of a catastrophic ice age. A great origin story worthy of our intellect.

Now Andrew Barr from the George Washington University (Signal or noise: significance of turnover pulses) has published a study which refutes the ice age theory. Instead it claims that simple random factors other than environmental shifts are likely to have caused these pulses.

W. Andrew Barr’s paper declares that the underlying cause of these pulses may be down to just chance. To prove it, he ran a series of computer simulations to model how the African fossil record might look without factoring in climate change. The results showed species clusters of a similar size to the real African fossil record. While it is true scientists can’t agree on what defines a cluster, Barr’s paper implies that species origination is more random than once believed. In other words, Homo, the most intelligent of species, may have come about from pure luck. A simple roll of the cosmic dice.

At first glance, it looks like our collective human ego has been dealt a massive blow. Barr believes his findings must prompt us to look for causes other than climate change for human evolution. He adds that our larger brains and technological prowess could have evolved for any number of prosaic reasons.

For those searching for meaning in life, Barr’s randomness of evolution may strike a deep disappointment in our hearts. It seems like our heroic backstory has been stripped away, leaving nothing but a primordial soup of arbitrary numbers.

This randomness of life’s origins suggests that we as high functioning individuals have no control over our own fate. However noble the vision of our destinies, we might as well wander aimlessly through our lives, subject to the vagaries of chance.

How does that alter our perception of life’s meaning? Moreover if all organisms are created by chance, what does this mean to be human? How does this shape our ego? If all species originate from random fluctuations over the course of time, then that makes us no better than amoebae. Our first thoughts might be that this is rather depressing for humankind. It’s far easier to have purpose to our lives when we believe we were shaped by an extreme external forces providing us a favourable (we, the clever-enoughs to survive) framework for our existence.

Science relentlessly seems to strip away the purpose in our lives, declaring we’re not as important in the scheme of things as we believe. Galileo risked inquisition from the Church by suggesting the Earth revolved around the Sun, implying Man was not the center of the Universe. Darwin theorized that all species evolve by natural selection and are not designed from scratch by some celestial being. From parallel multiverses to quantum mechanics, our sense of order and how we shape our destiny has been knocked time after time. Science has shown us to be tiny and inconsequential against the vast backdrop of space and time. With this latest paper, has Andrew Barr just thrown another pebble at the hubris of mankind?

However, before we get too disconsolate, we shall step back to have an overall picture.

First of all, we shall realize that randomness is integral to the fabric of life and universe. It’s been with us since the Big Bang and will exist to the universe’s last dying whisper. The molecules of a gas move around randomly, a process called Brownian motion. Volcanoes erupt through sudden shifts in the Earth’s tectonic plates, spewing destruction. An abrupt shift in temperature can trigger avalanches. Sunspot activity occurs at random resulting in magnetic storms affecting the Earth’s weather. Stars form and collapse into black holes, sucking other stars into oblivion. These are events are beyond our control, caused by forces of nature arbitrary and spontaneous from our point of view. They existed long before humans walked the earth and will continue long after.

Consequently Barr’s study didn’t uncover a new layer of randomness in life’s origins; it only shines a brighter light on the existing ones.

The real question we must ask is whether past randomness of our formation is a decisive factor of our meaning of lives. Is our past or our future is more important for us?

The answer depends on your personal views and preferences. One may think that the past, such as our ancestors and where we are coming from is more important than what we will do in the future. I don’t share this view. You cannot change the past, but you can define yourself and make your own decisions in the future.

Randomness might pervade all mechanisms of Nature, but it may not prevent us from forging a path toward our selected destiny. This chance is obviously depends on the existence of our free will, so further research is more than justified. But if we can meet this “minor” precondition, we can look for meaning outside the past whims of Nature.

Such future realization of the meaning of life is uncertain in almost all respect at best. We are all mortals, so our personal “futures” are limited. Even humanity’s existence in threatened by internal and external dangers. Individuals, whole groups and even entire societies have grossly different views on what is a worthy meaning of life. Nevertheless, we all, individually or together must look inside ourselves for a meaning of life. Raising a family, having a successful career, or travelling the world? Why not? Accomplishing our dreams during a finite lifespan of an individual or a hopefully very long existence of humanity may be the best we can hope for in a random world.

The Meaning Of Life Team

Citation

(Barr, W. (2017). Signal or noise? A null model method for evaluating the significance of turnover pulses. Paleobiology, 1-11. doi:10.1017/pab.2017.21 10.1017/pab.2017.21)