Understanding Evolution made me Vegan

Pleistocene hominins at Happisburgh
Ahh, the good old days- Illustration by John Sibbick

This is a reblog of a 2013 blog from Sentientist.org. 

I’m very often sent news stories that come out showing that meat (or other calorie dense foods seldom mentioned), helped expand human brain growth and reduce the interbirth interval in our species (enabling us to outcompete other nonhuman primates) or that the skeleton of a boy was found who died of apparent b-12 deficiency (because his mama was feeding him vegan, obviously). If eating meat is something humans evolved to do how can I argue against it from an evolutionary perspective? Here’s are my abbreviated arguments for being vegan.

1- Suffering is bad, mmkay*

If you don’t think that avoiding inflicting suffering whenever possible is a basic good then all the other arguments don’t fall into place (and I’d hate to meet you in a dark alley or legal vacuum). However, I have yet to meet anyone who really doesn’t think suffering is bad when they’re not arguing with me including using far-fetched thought experiments or talking about BDSM. If I asked you, for instance, whether it would be more moral to step on someone’s foot or to shoot someone in the foot you might have some intuitive grasp that one of these choices would be less painful for the unfortunate victim and thus less immoral.  To me, morality is about maximizing the well-being of others with my choices whenever possible, and I’m certainly not the only one. Indeed, it can be argued that this, or some relative form of utilitarianism is the basis for all secular morality. Certainly, those with religious beliefs who are also progressive tend to ignore “moral” teachings from religious texts that would cause suffering such as stoning people for a variety of offenses. †

2 – Vertebrates have the same capacity to suffer that humans do

My heuristic when it comes to suffering is that if an organism has the ability to escape pain it can feel pain (perhaps this is hyperadaptationist of me). However, pain is not the same thing as suffering. Suffering has been defined as the subjective awareness of one’s own pain. If you amputated my finger and somehow preserved the nerve endings you could subject my finger to all kinds of torture without any suffering (as long as I wasn’t terribly emotionally attached to what happened to it!). But what is suffering and pain, how do they differ and how can we know that any organism experiences either? Some may take it for granted that other humans have the same capacity to suffer (but it’s amazing how many engage in solipsistic arguments on the subject of nonhuman animals) that we experience personally, extrapolating that a conspecific, or member of the same species, has a similar subjective experience. However, this is a rational view (likely not mirrored in empathy for those who look different) and history, including the history of science, includes claims about some groups of humans not having the sentience to suffer. Pain and suffering are notoriously difficult to define as evinced by the fact that scientists don’t have complete consensus on when humans can feel pain (either developmentally or after brain damage) or even if specific organisms can feel pain. The total experience of pain is commonly divided into two parts: nociception, or the ability to experience noxious stimuli and pain, the subjective awareness of being in pain.

Nociception is the unconscious recognition by the nervous system that damage is occurring somewhere, but pain is the emotional sensation that whatever is damaged is hurting. (Braithwaite, 2010 pg 40)

Fish are the vertebrates we have the least intuitive empathy for but do they experience pain? Braithwaite (who wrote “Do Fish Feel Pain?“) collaborated on studies showing that fish have the hardware, that is the nerve endings and fibres, to experience nociceptionA followup study showed that fish in pain were distracted from normal novel stimuli avoidance, evidence that their attention was distracted by the nociception. I would call this latter phenomenon not just pain but suffering. I’ve never been someone who felt intuitive empathy for fish but just as I might not feel empathy for some humans or other organisms because of their dissimilarity to me I must rationally accept and give the benefit of the doubt to any organism that has a physiological system capable of nociception. If suffering is bad and I accept that vertebrates suffer then I must avoid harming them, especially when their suffering is going to be much greater than the pleasure that I can derive from it. Two loose ends on the vertebrates suffering question. Can’t humans suffer in an additional way?

The application of the principle of equality to the infliction of suffering is, in theory at least, fairly straightforward. Pain and suffering are bad and should be prevented or minimized, irrespective of the race, sex, or species of the being that suffers. How bad a pain is depends on how intense it is and how long it lasts, but pains of the same intensity and duration are equally bad, whether felt by humans or animals. When we come to consider the value of life, we cannot say quite so confidently that a life is a life, and equally valuable, whether it is a human life or an animal life. It would not be speciesist to hold that the life of a self-aware being, capable of abstract thought, of planning for the future, of complex acts of communication, and so on, is more valuable than the life of a being without these capacities. -Peter Singer

Humans can suffer insofar as their future preferences are thwarted and they can suffer emotionally and psychologically in a way that most nonhuman animals cannot. Say a man and a dog are both in a plane crash. The man as opposed to the dog might be considering how much he was looking forward to the birth of his first child and be gripped by horrible anxiety about the moment of impact. However, when a dog has the same experience he may not be gripped by longing for the future but he also has no idea how long the anxiety or suffering is going to last, has no idea that there is nothing he can do about it and cannot be reassured by considering his loved ones or an afterlife. Thus, the emotional and psychological suffering of humans over nonhuman animals, in my view, comes out in a draw. The other question is that of invertebrate suffering. I think, as a rule that invertebrates don’t suffer as acutely as vertebrates (with some exceptions) but I must admit that I haven’t thought as deeply about this issue as others have. I don’t think sea sponges and other sessile animals like oysters and mussels are worth moral consideration however I give motile animals the benefit of the doubt. I’ve followed up on this in a later blog about the ethics of being ostrovegan.

3- Humans have evolved moral blind spots for others’ suffering

That’s all well and good you might say but why not support humane animal agriculture? Aren’t there a lot of animals being raised for food whose lives are more pleasurable than painful and aren’t there a lot of farmers who love their animals and take excellent care of them? Our money should be going to these people! I didn’t want to go vegan. I spent about a year researching animal products to try to find those that met some specific standards so I could be a “humaneivore” (someone who only eats humane animal products) but I never found those minimum standards realized. These were: 1- The animals would be able to actualize all of their basic desires (e.g. dust bathing, rooting, forming bonds with conspecifics) 2- The animals would have no idea they were about to be slaughtered and not transported to slaughter 3- Animals would be killed painlessly 4- Animals would not be altered in any way without anesthetic (e.g. tail docking, debeaking, castration are all done, for the most part, without anesthetic) 5- Animals would receive adequate veterinary care so they did not suffer physically for very long (e.g. hens who have uterine prolapse most often die of it without any respite from what must be horrible suffering) Why are animal products where animals’ lives meet the above standards almost impossible to find? In brief, here are some of the conclusions I came to about human evolved psychology towards nonhuman animals. A farmer caring for an animal above and beyond the extent to which it’s profitable for him (and certainly people make good profits on animals that suffer terribly) would be behaving altruistically. Does altruism exist? From the perspective of evolutionary biology, altruism is defined as the phenomenon of an organism behaving in a way that helps other organisms at a cost to itself. This ‘‘cost’’ is what often trips us up because when you scratch the surface of altruism there is, more often than not, a genetic or other downstream benefit which makes acts not truly altruistic. There are two main types of altruism. Kin selection is helping others because they carry copies of your genes and is well represented well by the answer that J. B. S Haldane gave when asked if he would give his life to save his drowning brother. He said ‘‘No, but I would to save two brothers or eight cousins’’**. The inaptly named reciprocal altruism is helping others because there is some likelihood they will help you in the future, often summarized as “you scratch my back and I’ll scratch yours”. Singer rightly says that reciprocal altruism is:

 “not really altruism at all; itcould more accurately be described as enlightened self interest. One might bea fully reciprocating partner…without having the slightest concern for thewelfare of the person one helps’’

People also behave altruistically in order to signal their empathy or trustworthiness both as mates and in order to gain beneficial reputation and status. There’s a commonly  anecdote for this, although I’m not sure where it comes from. A professor and students are having a discussion about whether or not altruism exists. A student says “Just this morning I helped an old woman cross the road, surely that is altruistic!”. The professor says “well, yes it was, until you mentioned it.” The crux of my argument is that humans are poor custodians for nonhuman animals because our evolved psychology. 3a- Nonhuman animals give off few, if any, kinship cues. Animals, like dogs, who are bred to be neotenous fare better than many other species in human care but consider even how members of our own species are treated when they are unrelated to their caretaker. 3b- Nonhuman animals cannot (with few exceptions) reciprocate in social interactions in a way that is very advantageous to the actor. This inability to reciprocate is the basis for some arguments that nonhuman animals should be wholly outside the moral community. Thus, if we consider the cost benefit calculations that go into governing our beneficial actions towards others-this facet that arguably makes peaceful coexistence with other humans and economics possible- is almost totally absent with regard to our evolved cognition towards nonhuman animals. 3c- Most of our interactions with nonhuman animals are without reputational consequences. Nonhuman animals cannot tell anyone if they are being neglected or abused. One notable exception is companion animals like dogs and cats. Consider someone who thinks animals are not important morally and yet wears her elderly dog in a baby carrier. When animals are farmed by the billions for human consumption and companies have incentives to keep true information about animal treatment from the public we have a recipe for no possibility of reputation and deceptive labeling that allows the consumer to signal their good intentions towards animals while actually making very little difference to animals. Consider that these same aspects of evolved psychology are also going to be involved in anyone overseeing animal agriculture. I’m vegan because I think that human and nonhuman animal suffering is important morally, evolutionarily there is good evidence that all vertebrates suffer and human evolved psychology makes humans virtually unable to engage in consistent moral behavior towards animals in their care especially when these  animals are being raised for food. Is meat essential for human health from an evolutionary perspective? Why does abuse exist (when it seems much more costly than benign neglect)? Why are some people bending over backwards to take good care of animals? These are questions for later blogs.


*Avoiding inflicting suffering isn’t specifically derived from evolutionary principles. † It would be very interesting if someone would do a study of religious teachings that are ignored to see if these do not conform to any principle or set of principles. I have no doubt one major reason that edicts are closely adhered to rather than ignored are because they conform to utilitarian principles.

**i.e. both of these cases involve rescuing 100% of your genetic material if brothers on average contain 50% genetic material in common with you and cousins 1/8.  

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