Extinction Isn’t an End: Mining Ancient Innovation for Future Solutions

The study of biology has yielded incalculable human riches: We selectively breed animals and plants, we avert apocalyptic pandemics and ecosystem collapses, we forecast debilitating illnesses, we prolong our lifespans, and in some cases, we understand and control our own bodies down to the level of individual bits of our DNA. All of this is made possible by understanding our links to the organisms that surround, and inhabit, us.

In the context of this bounty of biological knowledge, where does the past — the study of our earliest ancestors — fit in? I’m not talking about our hominid cousins or even our cute distant kin, the social media-friendly warm-blooded mammals. I’m referring to the microorganisms that lived billions of years ago on the early Earth. These organisms are difficult to distinguish by the human eye, they barely resemble us, and, as Douglas Adams (The Hitchhiker’s Guide to the Galaxy) once wrote, “Humans are not proud of their ancestors, and rarely invite them round to dinner.” So why concern ourselves with the anatomy, physiology, and molecular biology of organisms that lived billions of years ago — presumably including many lineages that have long since perished — pruned away by the ferocity of fate and circumstance?

Evolution’s deepest illusion is the teleological impression it creates upon our minds. The classic “March of Progress” chart depicting a gradual change from ancestral primate to Homo sapiens is indelibly baked into the human psyche. But the truth of evolution is far more complicated, surprising, and beautiful: Most species that have ever lived have gone extinct, and many of these extinctions occurred through no fault of their own. They were quite fit to reproduce, but natural fluctuations or catastrophes occurred and ran them off the board. Among all populations of organisms that live at any given moment, almost none of them are part of a lineage that actually becomes measurably more complex within an observable number of generations. Why? Because there are many costs, and few benefits, to complexification in the short term — any additional feature is also something that can go wrong, and there are always far more ways to go wrong than to improve.

And yet, our attention seems to be drawn to the flukes of the bunch — the animals, the trees, the fungi; those organisms that defy the most probable outcome and seem to grow more complicated over time. There are abundant species around (both historically and currently) that are enormously successful at shifting, persisting, and adapting, while remaining more or less the way they are, and yet we give them short shrift in our attention. Even the simplest definition of evolution (succession with modification over time; descent of change from a common ancestor over generations) seems to bias modification as an additive process. The sense we are left with when we disregard all of this beautiful nuance in the arc of paleobiology is that the fittest were (naturally) going to make it, and the weakest were not.

This view is too simple, and misses a greater truth. Not everything is inherited, and elegant modifications can be simplifying as well as complexifying. When we choose to embrace all of the beautiful nuances of evolution, we can begin to appreciate paleobiology for what it is: a study of organisms that were fit … for their unique time and circumstances.

Paleobiology is therefore not a study of what has failed, but a study of what worked best under a specific set of conditions. A wider variety of conditions than are found on our planet today, in fact. What is innovation except something being built under conditions of high uncertainty, and as deemed fit for its time and place? Durability and utility can be artifacts of timing.

Applying this mindset to biology today

Bioengineering and biology-based solutions can therefore be much more powerful if they include all the solutions biology has generated to solve problems, and not just the thin slice that exists today. Evolution may indeed exhibit certain signs of temporal directionality — because biological histories can be, and often are, contingent — but environmental conditions are what they are, and nothing more. There is no fruitful, absolute basis of comparative fitness or inherent value to be extracted from variations in, say, high or low sulfur content, increased or decreased solar insolation, or freezing or boiling temperatures. 

The origin of life may be viewed as part of a continuum that links complex biology to complex geochemistry. Though the emergence of the first self-reproducing cell marked a singularity — a milestone of biological possibility that fixed the architecture of all cells to follow — there is little reason to surmise that the phase of chemical evolution that preceded biological evolution was significantly different or less complex. Recapitulating the origins of life may lead us to discover self-organizing, chemical solutions to problems that are no longer recorded in (or possible to be discovered through) living descendants.

Four billion years of struggle to survive means four billion years of living experience, of biomolecular tinkering, of exploring novelty and possibility that defy current conventional logic. It would be impossible to accumulate this magnitude of information through laboratory experimentation, and should therefore be viewed as a bioinformatic repository without comparison — a Library of Alexandria, not fully lost in the sands of time.

Treating this rich repository as such — combined with modern bioinformatics and molecular biology — not only affords us the opportunity to explore the successful “solutions” employed by both ancient and modern forms, but to leverage those solutions for modern-day problems. This goes far beyond notions of biomimicry, where engineering materials and solutions are modeled on biological ones and something visible today is copied in another form. It is about realizing that ancient biological solutions that have long since been forgotten can be entirely new, and useful, to us in the present.  

The CRISPR gene editing system, for instance — arguably the future of genetic engineering (and which went from discovery to practice to Nobel Prize recognition in a relatively short timespan) — is based on a bacteriophage that isn’t even really alive at all. It is hard to imagine a more distant biological entity from us, and yet this tool (and others like it) may shape the contours of human societal evolution for the next century. In this way, reaching into the past can become a means of connecting to an unfathomable range of functional molecular possibilities. It doesn’t particularly matter if the solutions involve our direct ancestors or our far-flung distant kin.

And the array of solutions can range from the mundane to the extraordinary. We may sample more efficient carbon-harvesting techniques for mitigating climate change, create artificial life forms that readily synthesize more ecologically compatible fertilizers, or uncover how molecular language processing in translation can be modified to synthesize entirely new classes of reactive artificial enzymes. Careful observers can begin to see that the next evolutionary phase of scientific exploration of ancient life on Earth may be far more interactive and beneficial than has been imagined: an exploration of new techniques that can bring past states to life to solve our current, and future, most pressing problems.

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  Betül Kaçar is a professor at the University of Arizona. She directs a NASA research consortium exploring the origins, evolution, and distribution of life in the Universe.

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