by Brian Tomasik
First written: April 2014; last update: 12 Nov. 2016


Scientists and futurists often encourage humanity to spread out into the galaxy, in order to reduce risks to human survival, build new civilizations, and bring life to desolate planets. One fairly realistic proposal is the terraforming of Mars, in which the Red Planet would be made increasingly hospitable to life, until plants and animals could be sent to live there. More speculatively, some have advocated "directed panspermia" -- disbursing genetic and microbial seeds of life into space in the hopes that a few will land on and populate other planets. Finally, some futurists imagine virtual worlds in which computational agents would interact; these would sometimes include animals in the wild.

In these scenarios, animals are proposed to be used as a means to help humans, as a vehicle for spreading life to the stars, or as part of realistic virtual environments. What is almost always ignored is that these animals would have feelings, and many would suffer enormously as a result of being created into Darwinian ecosystems in which predation, disease, and premature death are endemic. Theologians ask why a good God would create so much cruelty in nature. Future humans should likewise ponder whether it's morally acceptable to create new ecosystems containing vast amounts of suffering, or whether they should pause and seek more compassionate alternatives if they embark upon space colonization.

Keywords: wild animals, environmental ethics, terraforming, directed panspermia, virtual worlds

Note: The material in this piece was salvaged from a draft conference paper that I never finished. As a result, the flow of explanation is somewhat choppy.

Panbiotic ethics

Mautner (2009) proposes "biotic ethics," which intrinsically values the unique and complex properties of cellular DNA-based life, including its use of "self-reproducing gene/protein cycles." Life of any kind is valuable in this view, although Mautner (2009) says that we may favor happy conscious life if only because that can motivate creating more total life "from a human point of view."

Mautner (2009) goes further and proposes "panbiotic ethics," which has the goal of spreading life into the galaxy, with the objective of maximizing the amount of life that exists. In particular, he proposes to optimize the time-integral of life's mass over the future, measured in kg-years. He adds that "the quality of future life also matters, and in particular, we may wish to maximize conscious life."

Mautner (2009) suggests that when we ask "What is the purpose of life?" we see that organisms appear to answer this question by striving to survive and reproduce. Even creatures that lack conscious aims collectively optimize this goal in an implicit fashion. Mautner (2009) argues that this can motivate panbiotic ethics. I think his point is really equivocation, because "the purpose of life" can refer either to what we see life collectively trying to accomplish, or to what goals we as individuals may want to see fulfilled by our deliberative actions. The two may be very different, and it's the latter question that most people care about.


Terraforming is the process of changing a planet's atmosphere, chemical composition, and environmental conditions in order to make it habitable by life -- first extremophile micro-organisms, then potentially plants, and eventually maybe animals.

Curiosity Approaching Mars, Artist's ConceptFogg (2011) explains that terraforming was once "a speculative thought experiment" but "has been slowly gaining in respectability." He suggests that completely terraforming Mars to the point of containing animal life "is likely to remain a distant, although not impossible" feat. However, the basic stages of terraforming would also provide advantages. For instance, introducing a denser atmosphere to Mars would help with cosmic-ray shielding, flight, and reducing need for pressure suits (Fogg 2011).

Developing a self-sustaining colony on a planet would avoid the extremely expensive burden of transporting materials from a home planet (Fogg 2011).

Directed panspermia

Crick and Orgel (1973) proposed directed panspermia as a hypothesis for the origin of Earth-based life, though the authors note that showing panspermia to be possible does "not enable us to estimate the probability" that it actually occurred. The authors recognize the objection that panspermia just pushes the problem of life's origin one step back without solving it, but they suggest that alien origins might still have explanatory value, such as if conditions on another planet would have been more conducive to the advent of life than were conditions on primordial Earth.

Crick and Orgel (1973) note that stars like our sun would have begun forming around 11 billion years ago, but because Earth didn't form until about 4.5 billion years ago, this leaves 6.5 billion years during which life might have arisen elsewhere and then been dispersed to other planets, including Earth. The authors propose that directed panspermia might have been carried out by compiling samples of different microorganisms, such as cyanobacteria, with different survival requirements, to help ensure that at least some would have been able to thrive on habitable destination planets. And because the Milky Way is only 100,000 light-years in radius, a rocket ship could have traveled at just 0.1% the speed of light and still reached its destination within 100 million years, assuming the sending civilization was elsewhere in our galaxy. While it would have been possible to send not just bacterial-level life but also "mice or men" as well, doing so would have required more elaborate sustenance mechanisms, and it's not clear more complex life could have been sustained by freezing it to a temperature near absolute zero, while for bacteria doing so seems plausible.

Crick and Orgel (1973) suggest that while it's unclear what would motivate an alien civilization to spread life, we can imagine several possibilities. For instance, if the aliens were like our own civilization, they might have been motivated by "missionary zeal" with the goal that "the great majority of inhabitable planets could be given life by Directed Panspermia." The authors do note that panspermia could be ethically problematic, but they feel this way mainly if the target planet already had life of its own. They enjoin society against "infecting other planets at the present time" because we should learn more about how likely it is that life already exists elsewhere. However, the authors appear supportive of the project "if we became convinced that we were alone in the galaxy."

Crick and Orgel (1973):

We are thus free to postulate that there have been (and still are) many places in the galaxy where life could exist but that, in at least a fraction of them, after several billion years the chemical systems had not evolved to the point of self-replication and natural selection. Such planets, if they do exist, would form an excellent breeding ground for external micro-organisms. Note that because many, if not all, such planets would have a reducing atmosphere they would not be very hospitable to the higher forms of life as we know them on Earth.

I personally don't find it likely that a civilization would be so advanced as to spread biological material without also sending self-replicating spacecraft. In other words, I think the most numerous type of spacefaring life would be digital.

Defending a panspermia proposal called the "Genesis Project", Claudius Gros said: "Personally, I think life is beautiful. We should give it chance to flourish, even if we never see the result. [...] The Genesis Project gives humans a chance to leave a legacy."

Virtual wildlife

The prospect of spreading biological life is relatively tangible and clear. However, in the long run, it seems likely that most Earth-originating agents will be digital: Robots and other artificial intelligences (AIs).

Many experts expect that AI will surpass human intelligence within a few centuries. Even if it takes longer, it seems that AI should be possible in principle and is probably feasible for humans to figure out. So we should expect that digital, not biological, minds will dominate in the future, barring unforeseen technical difficulties or extreme bio-nostalgic preferences on the part of the colonizers.

Long-run computational power may be used for many purposes. Some would be necessary for the calculation and data-processing purposes to which computers are typically applied today. An advanced civilization would require immense amounts of planning, organization, robot development and deployment, and so on. Beyond maintenance, though, civilization would presumably also devote significant computation to some intrinsically desired purpose.

If human-like minds are in control, one leisure pursuit might be exploration of virtual worlds of various types. Perhaps descendants of nature-loving humans would want to explore what Earth's environment was like in the past. They might build a virtual world containing rocks, trees, grass -- and wild animals. To enhance the realism, these animals might contain life-like digital brains of their own, and hence they would consciously suffer upon being eaten or enduring harsh environmental conditions. Even virtual environments not explicitly intended to portray nature might contain wild animals in the background, or even just insects in a living room -- perhaps getting caught in a spider's web or buzzing into a hot lamp.

The virtual wild animals needn't just be similar to those found on Earth. Future people might create a vast array of alien-like or fantasy creatures. We can see adumbrations of such a future in present-day video games. Advanced non-player characters might endure painful events as they act in the background. Or they might even suffer more directly at the hands of virtual protagonists who battle monsters on their quests. While this situation is common in present-day video games, the monsters in future world simulations may be as computationally sophisticated, and hence as sentient, as real biological wild animals are today.

Entertainment is not the only plausible motivation for simulating digital wild animals. Future biologists and ethologists might want to learn more about the physiology and emergent behavior of their created creatures. Large-scale simulations might yield insights into the dynamics of evolution. Perhaps some environmentalists would even value nature for its own sake and seek to simulate it on a large scale, even (or perhaps especially) without intrusion by human observers.

Further commentary in video format


Thanks to Jesper Östman for suggesting the "problem of evil" angle on this issue.


Crick FHC, Orgel LE (1973) "Directed panspermia". Icarus 19(3):341-346.

Fogg MJ (2011) "Terraforming mars: A review of concepts". pp. 2217-2225

Mautner MN (2009) "Life-centered ethics, and the human future in space". Bioethics 23(8):433-440.