Life as We Made It How 50,000 Years of Human Innovation Refined – and Redefined – Nature

Books can be like buses: nothing is written on a topic for ages and then two appear in quick succession. The subtitle of Life as We Made It resembles that of the recently-reviewed Life Changing. Both books indeed cover the same topic: how humans have shaped the genetics and evolution of plants and animals around them. Despite some inevitable overlap, Beth Shapiro draws on two decades of her career as a geneticist to make Life as We Made It a beast all of its own. I found myself both thoroughly enjoying her fantastic science communication while disagreeing with her outlook.

Shapiro's particular speciality is ancient DNA: the DNA recovered from extinct organisms and archaeological remains, which are genetic time capsules that have given us astounding insights. Her book is divided into two parts, one looking at our past through the lens of ancient DNA, the other looking to our future through the lens of biotechnology.

The first half of the book is an absolute joy to read, showing what ancient DNA reveals about the influence of humans on life around them. This includes the evolution of the bison, charting their decline, temporary recovery, and then near-demise at our hands. She shows human evolution is a complex history of mixing and migration. She examines megafaunal mass extinction and the ongoing debate over how much to attribute to climate change vs. human hunting. She covers the process of animal domestication and how it affected both the genetics of animals and ourselves. And, finally, she looks at very recent extinctions (e.g. the passenger pigeon), the problem of invasive species, and the rise of the conservation movement.

The second half of the book looks ahead, tackling the genetic modification of crops and livestock and the broad resistance it encounters in society. Shapiro looks at length at some of the initiatives that use biotechnological tools to save species from extinction. She carefully and cautiously considers the topic of de-extinction and comes away not entirely convinced it is a good idea. Simultaneously, the recent development of gene editing tools has raised the possibility of ridding the world of certain pests and disease vectors, such as the mosquito species that carry malaria. There is an extended discussion about gene drives, CRISPR, and the science and ethics of editing the human genome.

What stands out is just how accessible all this material is, despite the range of subjects covered. Shapiro has a knack for communicating clearly, throwing in amusing anecdotes and self-deprecating humour as she recounts some of her academic bloopers. The annotated bibliography is a welcome bonus. More importantly, she retains the finesse and detail of these complex topics, repeatedly demonstrating how careful research refines simplistic narratives. Take one of archaeology's most enduring discussions: how we peopled the Americas. Analysis of bison bones suggests that humans coming over the Bering land bridge had already moved southwards, using a coastal route to bypass the glaciers covering North America before an ice-free corridor opened up. Similarly, popular science articles often exclaim how other animals, e.g. ants, also farm. Although such mutualisms look like domestication, "neither species intentionally modified the other" (p. 113), which is a key difference from what humans do. And the ability of humans to digest lactose does not correlate strictly with the practice of dairy farming, either now or in the past.

Despite thoroughly enjoying Shapiro's presentation of complex scientific topics, I also found myself disagreeing with her optimistic techno-driven outlook. This is perhaps nowhere more apparent than when she writes that "we are too embedded, our technologies too advanced, our population too large to disentangle ourselves from the habitats that we have invaded over the last 200,000 or so years [...]. We must use our increasingly advanced technologies to shape the future into one in which people can thrive alongside other species" (p. 102).

I beg to differ.

Before I climb on that soapbox, let me clarify that I am not anti-science. I share Shapiro's frustration about people's irrational resistance to GMOs and have previously written about the appeal to nature fallacy. For me, horizontal gene transfer is proof positive that nature beat us at the game of transgenics ages ago. Maybe it was not her intention, but it is a bit of a straw man to paint all opponents of biotechnology as either hostile to, or not knowledgeable about science. There are other reasons to have concerns.

Shapiro recognizes that overpopulation and overconsumption are at the root of many environmental problems. I ask you: since when have technofixes ever caused us to want less of something? Since when, as she mentions throughout this book, have new technologies not caused new problems or had unintended consequences? To propose that we embrace our role as Earth's stewards takes human dominance of the planet as a given.

Let me be clear: I do not think this is an either-or proposition. However, having reviewed both Abundant Earth and Limits I question the anthropocentric notion that we are entitled to keep shaping the world around us for our benefit. Its long history is no justification. Shapiro concludes that "the world is changing, and people and animals and ecosystems are suffering. Biotechnologies give us the power to help" (p. 290). I agree that we will need the best science can give us and she gives good examples where these solutions are desirable, such as introducing disease resistance genes into the nearly-extinct American chestnut. However, these tools are not the only option available to us, nor always the best. In many cases, biotechnology will only encourage the status quo of more economic growth and more consumption, not less. She observes that "we are aware in ways that our ancestors were not of the consequences of getting what we want" (p. 132). How about us not always getting what we want? If behavioural change and cultivating an ethos of self-limitation, both on an individual and societal level, can address problems, should we not consider this first? It strikes me that currently this notion rarely enters the conversation. That is my challenge to her and the research community at large, to consider that prevention is better than a cure and, with that in mind, to re-evaluate proposed technofixes.

This difference in outlook did not stop me from tremendously enjoying Life as We Made It. Shapiro is a fantastic science communicator who addresses the many nuances of each topic she touches, and she can be disarmingly funny. I heartily recommend you read this book, but I also invite you to afterwards critically reflect on her ideas in light of what I have written above.