The most fundamental question that, surprisingly, does not have a definitive answer.

Biologists and philosophers, from Aristotle to Oparin, have made numerous attempts to provide insightful answers, yet the pure essence of what we consider life remains elusive.

While this is a deep mystery, why should we care? For a simple reason: it would completely change the way we think about ourselves and our place in the universe. Instead of being the triumphant pinnacle of evolution that we make ourselves to be, by exploring the broader range of the attributes of what we consider living, we could fall into the realization that we are nothing but one of the possible results of the process called life.

Furthermore, when you consider the broadness of it, life as we know it might be but a tiny subset of all the possibilities of life as it can be. We always hear about the search for signs of life in other planets, but what kind of life are we looking for? Could we even recognize it if we are only looking for our own familiar, carbon-based forms?

Is life as we know it the only possible life? (Source.)

As a biologist –somehow surprisingly– I did not really think about the nature of life in depth, at least at the beginning: it was a concept that I took for granted. I mean, if you look around you, it is clear: all the animals, people, and vegetation around you –we can all agree they are alive.

However, something strange happens when you start looking at things in a microscopic scale: all these unfamiliar tiny machines, with their abstract shapes and configurations that seem to operate like little automatons.

https://youtu.be/mfQjIgbT-4g

In this beautiful video we can see several ciliate microorganisms swimming freely. There are calcium phosphate crystals embedded in the numerous vacoules (the bubble-like structures that look like beads in the video) contained in each individual, which makes them shine brightly under polarized light, making them look like they are filled with gemstones!

What is it then, that elusive quality that distinguish in animated objects from living beings? To begin with, is life a discrete quality, or is it a continuum? Is it a binary state, where things are either dead or alive with nothing in between (in a similar way that one cannot be “a little pregnant”), or can we say that something is “more alive” compared to another entity?

As scientific breakthroughs have advanced, Biologists have come up with some sort of check list of basic characteristics that a living being must possess:

Interactive with the environment, exchange nutrients and energy to function.
Reproduction, being able to make copies of itself.
Self-contained, transmissible information in the fashion of a executable genetic program.
Evolutionary potential: possessing genetic information that can be copied and/or modified in response to environmental pressure.
Self-organizing system, a mechanism that actively fights against entropy in order to prosper (this characteristic, termed Autopoiesis, is a whole fascinating topic in itself, which might merit its own article).

Based on this list we can get some insight regarding the nature of what we understand as life. For once, life does not seem to be a single property, but more of a meta property. Under this light of properties that life encompasses, we start to realize that life looks more like a continuum rather than a "yes or no" answer. In a way, we could say that some things are more alive than others.

Indeed, as we add to this laundry list of characteristics of life, we can see that things become problematic. Funnily enough, a great deal of the knowledge that has been obtained about living beings comes from investigating them from the point of view of them being a type of machine. However, when confronted with other entities that share characteristics that we use to describe life as a process, we suddenly feel a very strong reticence to consider them alive.

The study of a life outside of the carbon-based one that we are so familiar with, though, might be out of our conceptual reach. However, it is undeniable that such complex and continuously evolving systems of information exist. Some could argue that complex systems like cities are alive; also certain kinds of computer software... even the Blockchain!

There is one tool that can allow us to look at the process of life as an outsider of sorts (since it is obvious that being immerse in it creates some conceptual and philosophical problems), and that is the creation and exploration of life produced in silico, or as some have termed it, Artificial Life. This is a fascinating field that has helped to bring light to many fundamental issues in Biology, which merits a further discussion, so stay tuned!

An example of artificial life forms, in which the progeny produced in later generations grows in complexity after "mutations" being selected and combined, based in the initial characteristics of their ancestors. (Source)

We are constantly expanding our limits into the unknown, if we constrain ourselves into the limited fragment that we experience regularly, instead of trying to look at a bigger whole we are limiting ourselves to gazing to a fraction of the possibilities.

Keep an open mind, and let's explore together!

Cheers,

Irime

***

NOTE: An Ecosystem of Excess

The first picture in this post was taken during one of the most interesting art exhibitions I have visited here in Berlin: An Ecosystem of Excess, by Turkish artist Pinar Yoldas.

Here, the artist "created" her own life forms as imagined in a far distant future were organisms had evolved to feed on the plastic waste created by humans.

Description of the exhibition by Cornucopia Magazine:

With An Ecosystem of Excess, the Turkish artist Pinar Yoldaş creates a post-human ecosystem of speculative organisms and their imagined environment. The Great Pacific Garbage Patch, a garbage vortex made up of several million tons of plastic waste in the North Pacific about the size of Central Europe is Yoldaş’ site of interest and the birthplace for species of excess.

According to the “primordial soup” theory, life on earth began four billion years ago in the oceans, when inorganic matter turned into organic molecules. Today, the oceans have become a plastic soup. Seeing this as a site of exchange between organic and synthetic matter, of fusion between nature and culture, Pinar Yoldaş asks what life forms would emerge from the primeval sludge of today’s oceans. Her answer: An Ecosystem of Excess– a new biological taxonomy of the species of excess.

She came up with all sorts of clever ideas for especial organs designed for the breaking and assimilating of their feeding substrate, as well as intricate designs for each organism, and even a little bit about the ecology and interaction between population of these fantastic species. Amazing, isn't it?