A vivid account of the evolution of minds will fill readers with wonder — and challenge how they think about their moral responsibility to protect the planet

Great power and great responsibility: how consciousness changes the world

A vivid account of the evolution of minds will fill readers with wonder — and challenge how they think about their moral responsibility to protect the planet

Living on Earth: Life, Consciousness and the Making of the Natural World Peter Godfrey-Smith William Collins (2024)

Philosopher Peter Godfrey-Smith has devoted his career to examining how animal minds evolved. He blends formidable analytical skills with a deep curiosity about the natural world, mostly experienced at first hand in his native Australia. While writing his latest book, Living on Earth, he spent many hours scrutinizing noisy parrots and cockatoos in his back garden, weeks observing gobies building underwater towers made of shells and seaweed and years closely watching how octopuses behave (P. Godfrey-Smith et al. PLoS ONE 17, e0276482; 2022). The result is an inclusive perspective on Earth’s many distinct minds and agents that urges readers to consider humans’ collective choices and their diverse consequences.

Living on Earth offers an extended philosophical meditation on life, mind, the world and our place in it, completing a trilogy of works on the nexus of agency, sensation and felt experience. His 2016 book Other Minds explored octopus cognition and evolution. And Metazoa (2020) appraised the subjective experiences of animals, concluding that there exists an “animal way of being” that arises from the integration of sensory information in nervous systems. This implies that sentience and subjectivity — life-shaping combinations of perception, goals and values — are widespread across the tree of life.

In his latest book, the author casts his net wider still, asking how the minds and agency of living things have affected Earth. “The history of life is not just a series of new creatures appearing on the stage,” he notes. “The new arrivals change the stage itself.”

The arrival of animals

Godfrey-Smith starts by explaining how the earliest lifeforms altered our planet’s chemistry and geology. Photosynthetic bacteria released oxygen, which gradually blanketed Earth and left their mark on the composition of rocks and minerals in the form of new minerals, such as malachite. Eventually, enough oxygen accumulated to power the evolution of aerobic life — a stark example of the transformative impact of some lineages constructing environments in which others can thrive.

The arrival of animals that could undertake purposeful actions, such as feeding, interacting with others and gathering information, meant that Earth was transformed further. As their capacities for controlled movement evolved, animals became able to actively engineer their environments. Defecating migrating whales, for instance, redistribute nutrients and support other species in the food web, which in turn benefits the whales.

Focusing on communication, Godfrey-Smith describes its powerful effects with a riot of avian sound and colour. On a rainforest walk, he encounters a lyrebird (Menura sp.), known for its expert mimicry, which it uses in part to attract mates. “In quick succession, he was a whipbird, a black cockatoo, a Laughing Kookaburra, a magpie, and many I didn’t know”. Fork-tailed drongos (Dicrurus adsimilis) use alarm calls copied from other species, to cheat other species out of well-earned meals (T. P. Flower et al. Science 344, 513–516; 2014). This capacity to deceive, as well as to communicate honestly, further transforms what an organism can experience and what effect it has on its surroundings, by creating ever-changing visual and audio environments.

Turning to hominids, the author considers culture, which he characterizes as the ability to learn sets of norms that are passed between peers and down generations. Humans are primed for such learning, exhibiting an awareness of rules early in childhood. He argues that the ways in which people help others to learn those norms — through informal apprenticeships, for example, in which older individuals teach skills to younger ones — sets us apart from many other species. They have also enabled humans to develop distinctive aspects of communication, such as an ability to understand from a person’s words what they are thinking. This skill makes it possible to coordinate behaviour more effectively, helping people to live together in large, stationary communities and thereby increase humanity’s ability to control and modify nature, for good or ill.

Human influences

The fact that humans can exert agency in many ways — through physical actions, culture and communication — goes hand in hand with increased abilities to change the world. Thus, Godfrey-Smith argues, all these aspects of human agency come with a responsibility to think hard about what forms of control or modification of other living beings are ethical. Our intuitions of harm, fairness and loyalty, along with basic norms derived from habits of nurture and protection, such as caring for one’s offspring, must all be considered to define moral imperatives for societal behaviour towards all forms of life.

Take modern industrial farming — which should cease, the author contends. People can understand how it arose from the need to feed growing communities. But individuals can also engage in imaginative and sympathetic ethical reflection that considers the lives of factory-farmed animals. If the animals that humanity controls in this manner do not seem to have “a life worth living”, Godfrey-Smith asserts, people should acknowledge that these practices are unethical.

However, that doesn’t mean it’s obvious what should be done instead. Godfrey-Smith emphasizes that the most ethical choice is not necessarily to relinquish control over other living beings and stop farming. After all, human actions of control and modification are part of the natural world, too. Some people might advocate justly that humane farming — such as raising animals in environments with the freedom to roam and a healthy diet, or using effective stunning methods before they’re killed — is an appropriate solution. Others might think this is a contradiction in terms.

The author is well aware that human actions have produced huge, planet-wide problems, including climate change. However, he encourages people to use their agency and address such problems on a local level, at scales that individuals can most readily influence. For example, I am more likely to be effective at improving habitats by coordinating with members of my local township to reduce the waste that enters a nearby ecosystem than at reducing fossil-fuel use by industry worldwide.

Controversially, Godfrey-Smith wants us to see our moral responses to these two types of problem — habitat degradation and climate change — as separable. This is in part because they prompt different types of ethical reflection and in part because they demand distinct kinds of coordinated control and modification. In terms of ethical reflection, people are more likely to take actions that support and protect the lives and experiences of other species when they value them explicitly. The lives of local bird or butterfly populations are more tangible, and so easier to value, than is life on a global scale. And in terms of coordinated control, collaborative efforts with one’s neighbours can have great staying power and effectiveness at a scale that differs from governmental policies that provide incentives for individual consumers across society.

In places, Godfrey-Smith’s considered tone and judicious presentation of subtleties might seem frustrating, considering the stark situations we face because of humanity’s misused agency. If ‘we’ are in this together with other life on Earth, then don’t we need to act accordingly (and urgently)? Yet solutions are not black and white. For example, reducing pain by experimenting on fewer animals does not necessarily mean that researchers should aim to cease experimentation for medical benefit. Such trade-offs are central to Godfrey-Smith’s narrative and what make it so insightful.

Overall, Living on Earth successfully fills readers with wonder at the natural world, while maintaining a clear, analytical style. Godfrey-Smith argues compellingly that, although we live in a world shared with other species, humans have distinctive responsibilities because of the “unusual efficacy in our actions”. I tip my hat to his uncanny ability to make his case in a temperate voice with both intellectual acuity and passionate conviction.

Nature 636, 32-34 (2024)

doi: https://doi.org/10.1038/d41586-024-03916-y

This story originally appeared on: Nature - Author:Alan C. Love