The Evolutionary Roots of Religious Adaptation
Chelsea Strayer, a PhD candidate in Biological and Cultural Anthropology at Boston University, examines the evolutionary psychology behind religious belief and adaptation. She explains how religion functions as a byproduct of earlier evolutionary adaptations—including social susceptibility, hyperactive agency detection, and the need for stable social hierarchies—that helped humans survive as highly dependent social creatures. Strayer argues that understanding these biological and cultural mechanisms is essential for appreciating religion's powerful role in shaping human health, social bonds, and coping strategies, while acknowledging both its benefits and trade-offs.

Chelsea Shields is a biocultural anthropologist, TED Fellow, and researcher whose work explores the evolutionary foundations of religious belief and the physiological power of social connection. Raised in a Latter-day Saint family in Utah, she went on to earn dual PhDs in biological and cultural anthropology from Boston University in 2017. ¶ Shields’ academic research focuses on the concept of social susceptibility—how human bodies have evolved to be deeply responsive to social interaction and meaning-making. Over the course of a decade, she conducted extensive fieldwork with Asante indigenous healers in central Ghana, studying the evolution and elicitation of placebo and nocebo effects in ritual healing ceremonies. Her dissertation, “The Social Life of Placebos,” argues that grounding human behavior in social adaptations reveals important discoveries across placebo studies, religion, pain, stress, and empathy. She presented at the 2014 Conference of the Mormon Transhumanist Association on the evolutionary psychology of religion, examining how religious belief functions as a powerful biocultural force—shaping neural development, social bonding, and coping mechanisms—and how understanding these processes is essential for anyone thinking seriously about the future of the human brain and body. ¶ Shields is a three-time TED speaker, an advocate for gender equality within religious communities, and founder of Brandthropologie Agency, where she applies her research in social susceptibility and nonverbal communication to brand strategy and consumer research. She lives in Salt Lake City with her family.
Transcript
Speaker 1
Our next speaker is Chelsea Strayer, a PhD candidate at Boston University in Biological and Cultural Anthropology. Studying the evolution and elicitation of placebo and nocebo effects in indigenous ritual healing ceremonies. She particularly focuses on the healing rituals of the Asanti in central Ghana, whom she has conducted research with for over 12 years. Chelsea is also a well known religious gender equality activist in the Mormon community, president of Mormons for ERA, co founder of LDS Wave, and active participant in many LDS magazines, blogs, podcasts and conferences. She’s a TED Fellow and has presented her research at two TED events. Please welcome Chelsea Strayer.
Chelsea Strayer
Thank you. I’m glad to be here. I’m going to. take it in just a little bit of a different direction. My objective being, we can’t contribute to the future, especially of our brains and bodies, if we don’t understand how they developed. Or as I’ve learned today, From Adam, if you don’t know how and why the frog developed, right, the proximate in the evolutionary mechanism You can’t put it back together, right? So, only everyone who’s coming that isn’t the transhumanist are like, what does that mean? It’s a fascinating thing to be able to sit here and listen to the. the story so far and all everyone’s perspectives.
Chelsea Strayer
I’m going to start real quick with a story, like Micah was saying earlier. It’s kind of a crazy story. It’s kind of weird, but I promise it will tie in. I’m an anthropologist and I’ve been doing research in West Africa back and forth for the last decade. And I have a story about this word, okay? Not that way, in a different way. When I first started doing research, I was only twenty years old. Started making friends. We became such good friends, I used colloquial language often. And I used this word, I guess, at the time, a decade ago, I used the word crap. Oh, that That tastes like crap. It was just a word we used. Well, some of my Ghanaian informants started using this word. Oh, this thing is crap. Because they picked it up from us, just as we pick up culture and we transmit it.
Chelsea Strayer
Well, what happened one day was that this informant named Paul he went to go see his accountant, and his accountant had stolen money from him. He was very upset, and in the process of walking into his office and yelling at him, You stole all this money from me, he says You are a crab man And he’s trying to say this word crap that I had unconsciously taught him. But with the accent and with the idea that no one else in that room had ever heard this word used Everyone thought he was saying, You are a clubman, okay? Which wouldn’t have been a problem, except for his accountant had been paralyzed from polio And walked on the ground with just his arms. So the minute that Paul said that, no one listened to his complaints about getting screwed over financially. People were offended that he was making fun of this person’s physical body.
Chelsea Strayer
The reason I bring up this story, which sounds kind of strange, I admit, okay? The reason I bring up this story is because the people listening weren’t capable of subsuming the information that Paul was giving them because they were offended by the form in which it was coming. They were offended by what they thought he was saying. At the same time, Paul had real information to give, and he wasn’t able to communicate that information. Because people were offended, right? And we see this all the time. Information being disregarded by people with whom it could be used. utilized and made better because of the form it’s given and or because of the words used that are not that are not the same in different contexts. Right? Or on the other hand, people who think they’re right saying it in such an offensive way that it can’t be listened to.
Chelsea Strayer
I see this all the time in the scientific study of religion with religious scholars and with religious believers. So we have religious scholars trying to explain the scientific, you know, religious brain project, which Michael will talk about next, or trying to explain the evolutionary psychology of religion. And what we’re getting is there’s a big divide, a big lacuna between the people doing the science and the people doing the believing, because one’s offended. and what the information’s not getting passed and or the people giving it aren’t doing it in a good way. So this is kind of where I see myself a little bit bridging the gap as both a religious person and as a religious scholar. studying the scientific study of religion. So I hope we can kind of bridge that gap and explain some of these things.
Chelsea Strayer
Well, one of the problems is, is Often we’re discussing the process, not the purpose. So every time I teach an evolution class, and I have one of my students here, I start the class saying, Look, I’m explaining the process of phylogenetic and ontogenetic development, how your body changes over time. Whether you want to debate how it came to be, how the universe was first Came to be, or your body first came to be, that’s a different process. Whether we want to talk about the purposefulness of Of the evolutionary process, again, a different process. We’re talking process, not purpose, which relates to anyone, the scholar and the religious student. So the process is fascinating in and of itself.
Chelsea Strayer
and I teach my classes and I have one student walk away from my class just as the same as my lectures, and one will say, Hey, you just told me that God doesn’t exist. You just proved that. And I’ll have the same student be like, You just proved that God is the smartest person ever. Right? And I’ll have my two students. Same lecture, walk away with both of those. So, I don’t care which way you go, but the process is still important.
Chelsea Strayer
So, for example, there are very real biological consequences to religious belief. There’s epigenetic changes, there’s symactic connections, there’s neural development, there’s ontogenetic, developmental. absolutely measurable changes in the body to religious belief. And until we take that seriously, religion as a causative factor in our biology, we can’t take it seriously. as a future causative factor and or as a solution to problems, K.
Chelsea Strayer
At the same time, we tend not to take culture seriously We tend not to take it the real cultural impact of religions. Look at our history. The impact of religions on our socio-cultural institutions are remarkable. It is not an abstract oh, well, just stop believing, just change religions. It’s not easy, it’s not simple like that. And so to take both of these Things seriously is important.
Chelsea Strayer
But it’s important for me as in what I do, the evolutionary psychology of religion, for a particular reason. The reason it’s important for me is that we have a biocultural evolutionary past where these two things are mutually interpenetrating and influencing each other. So much so that who we are now, the way our brains developed, the way our bodies developed, are based on this back and forth between biology and culture. Okay, so much so that as we conquered our ecological pressures, i. e. , I’m not worried about the saber-toothed tiger 150,000 years ago, I figured that out. I created tools, right? Our religions become the selective pressures through which our bodies adjust.
Chelsea Strayer
So we’re no longer, look in your room, look at the room right now. In what capacity are we evolving or adapting or having a physical constraint to evolutionary or ecological pressures? Almost nothing. From the temperature in this room to access to air, we’ve constructed that. We created air ducts, we created air conditioners. We are now, our bodies are now adjusting to the things we created. So, why that’s important is we create our own cultural constraints, the pressures through which we evolve, which is important as we begin to explore the future.
Chelsea Strayer
So let me walk through just a couple slides on religion as a byproduct of other adaptations or religion. As an adaptation. The reason why we often don’t say religion as an adaptation in and of itself is because it’s so multifaceted, but also because religion itself Many aspects which make it memorable, long lasting, poignant, influential, ubiquitous have to do with previous adaptations. That had nothing to do with religion. And that’s why we think of religion as a spandrel or a byproduct that basically co-opted and very brilliantly. uses these neural mechanisms that evolved for other reasons. And I’ll explain a couple of those real quick, okay?
Chelsea Strayer
One is called social susceptibility. What this is, is that we were born in our evolutionary past So, at this unique time period, where with bipedality, the human pelvis constraints, and our huge encephalitis brains, there’s a period we had to be born before we were ready, and we are. Humans have one of the highest degrees of encephalitis. Well, we do have the highest degree of encephalitization of any species. And we’re born, and our brains grow 100% within the first year. So we’re basically born almost like a marsupial with our brains just completely growing at an exponential rate. During that time period, there’s an enormous amount, enormous amount of plasticity. to where culture can become embedded into our neurology, where culture can get under the skin, because our brain is now developing in a culture environment. Not necessarily only an ecological one.
Chelsea Strayer
At the same time, because we’re so dependent, human species are the most dependent animal on the planet, we have an enormous Press social pressure. We have enormous hyperattachment more than any other animal on the planet. We are dependent one hundred percent on caregivers for our survival. If you don’t care for me, I die. So we have this hyperattachment, which creates these other adaptations. We have these social warning systems. If mother leaves the room, we have a distressing cry, right? Please take care of me. Babies have hundreds of adaptations to get you to take care of them. And these don’t go away when we grow up. As we grow up, we still have, every one of us in the room, even though we hide it because it’s not cool, we still have the, please take care of me, don’t hurt me, don’t be mean to me, please. Don’t hurt me, take care of me, please. Don’t be mean to me. We want to belong. We want to be attached. We still find a lot of our mental health problems today, a lot of our physical health problems today, are a lack of a strong social support network. Okay.
Chelsea Strayer
We have, I can go on for a long time. The main point of this is that the fitness consequences of belonging and ostracism exponentially outweigh those of logical consistency even at the biological level. So much so that in the Pleistocene, if I did not believe my religion I’d probably probably still survive. There’s no evolutionary pressure to select me out. However, if I did not believe my religion and was cast out of my society, the chances of death are imminent. So the social pressure, the social foundation of religious belief is something that can’t be neglected. And often in religious studies, we cognitively assess religion, we forget, and we need to more talk more about the social appraisers of religious belief.
Chelsea Strayer
One of those things is costly signals of group commitment because we’re constantly socially vigilant, and I’ll tell you some of the consequences of that in just a second. It’s quite damaging on your body. Think about it. In the Pleistocene, in the EEA, we had, what, five cousins in lineage-based society. We maybe faced rejection once a week, maybe. Think of your teenage child today. How many cohorts did they talk to, speak to, or are influenced by on a daily basis? Hundreds. Not just physically, socially, social media, virtually. They can read fiction, they can watch a show. They are constantly. Being bombarded by these social cues, which means that they’re constantly on vigilance. Do they like me? Am I attached? Do I have high status? It’s very damaging to your brain and body.
Chelsea Strayer
One of the ways that our bodies or our social systems have evolved to take care of that constant social vigilance, which isn’t healthy, is to start trusting each other. If I know you’re looking out for the Saberdooth tiger, which, you know, it We’ll talk about time periods later. It’s just a joke. Then I don’t have to constantly be looking for that. And I can trust you, but I have to trust you. You have to show me a costly signal that you’re going to watch my back, or else I can never relax enough. to go and actually have, you know, sleep, to feel safe. If I’m constantly on the lookout, same with social interactions. If I’m constantly on the lookout, I can never be healthy. We’re on a constant state of stress. So we have to trust each other.
Chelsea Strayer
We also have to have what’s called a stable status hierarchies. When the hierarchies are always up and down and you don’t know who’s your alley or your foe, This is time periods where we see individual and social stress at a high, high, high rate. Physical mental health problems, societal health problems, when we see these status hierarchies. Disrupted, and religions provide some of the most stable hierarchies of any system that we’ve ever found. And they stay stable because at the very top is not just a man, it’s typically a God. That’s a pretty stable guy, who we say is perfect Unchanging, right? Unswayed, omniscient. That’s pretty stable. That makes us feel good. It gets us, okay, I can trust all of that, and then I can focus on something else in our life. It’s very healthy.
Chelsea Strayer
Other thing is, and I’m going to go through this pretty quick here, is religions provide mutually reinforcing Cognitive appraisals. So that something as non-reflective as please take care of me, don’t hurt me, as basic and biological as that is, religious beliefs. are tacked or put right on top of non-reflective beliefs. So that a reflective belief would be something I had to think about. There’s someone in the sky Who has power, who we can’t see, who influences the world. This is something I’m going to have to think about. I’m going to have to rationalize about. That’s hard to become ingrained. That’s hard to be default. Reflective beliefs are hard to be universal, but when they’re put on top of non-reflective beliefs like, please take care of me, please love me, please don’t hurt me, boom. It becomes plausible, it becomes understandable, it becomes emotionally persuasive. So all religious organizations are founded on this principle of a reflective belief being rooted in a non-reflective.
Chelsea Strayer
The next thing, sorry about that, that we have is what we call hyperagency detection devices. Most people who see this picture, the first thing they think of is otter. Some kind of animal. Our brains are made that way. If I’m walking through the savanna and the bushes move and I react and I move and I get ready to flee or fight, my chances of survival, even if it’s the wind. I hire than the person who says, eh, it’s probably the wind, and they get eaten by a lion, right? So every person in this room has radically hyperactive agency detection devices. Think about when you were a kid and the blinds moved in your room, you thought, There’s a monster. You didn’t think, oh, it’s probably an inanimate unagent. Okay?
Chelsea Strayer
So our brains are made by default to think agency, and we see this in the history of religious development. early spiritualist churches, animistic churches, where trees, winds, and every animal, every sky, every cloud, every being, every supernatural type of God had an agent. Okay, there was an agency there, a will. Everything was attributed with this kind of will. And because of this, your brain seeks this out. And this is when I say religion is a byproduct. This didn’t happen for religion. Either God’s a genius, or I just explained religion away. No, I’m just kidding. But, however, religious belief becomes. Quite understandable if your brain is made to think of anything as an agent, right?
Chelsea Strayer
The next part that’s one of the next byproduct that’s important is this concept of minimally counterintuitive concepts. Not every idea you will ever have lasts. Most of them you’ll never hear about again. We waste so much of our time and energy. Most things from the past do not you know, are not inculcated in our children. Only certain advertising campaigns, only certain we can call them memes, although I hate that phrase, only certain ideas are long lasting, memorable, and transmitted. We can actually go back and record what ideas have been passed on through time. What ideas have been transmitted at higher rates than any ideas, and guess what it comes down to? Religious ideas last longer. Okay.
Chelsea Strayer
And one of the reasons for this is that they’re minimally counterintuitive. If I told you a story today about walking my dog, everyone in the room would forget it by tomorrow. And in 10 years, if you said, what did you talk about? You would never say walking my dog. But if I told you a story about walking my purple dog, who has its feet on backwards. You would never forget that story. And in ten years, you would tell your kids she talked about this dog that was purple and their feet were on backwards. You would always remember that, because it’s just minimally counterintuitive enough.
Chelsea Strayer
For example, in class the other day, one of my students said. My parents told me that when the tooth fairy comes, they take the teeth and they put it in the spray can. That’s why when you shake a spray can, it goes To this day, she’s 30 years old. Every time a spray can go, she thinks there’s teeth in there. Right? This is how religious ideas get spread. The virgin mother. Is a minimally counterintuitive concept. So understanding how the brain works is critical in understanding why certain ideas persist and certain ideas don’t. And I’ll just end real quick with this slide.
Chelsea Strayer
Because religion is a byproduct, it’s not necessarily a purposeful thing. It adapted to do these good things. It helped us ease the social pain, reduce stress, modulate emotion. It radically makes us more socially supportive of each other. If we share the same religion, I’m ten times more likely to do something for you, to create a reciprocal relationship. It gives us control and order. It gives us meaning. It helps us cope with the world, especially with the first two things happening. We have a mismatch. Our brains and bodies were not meant to be experiencing the type of complexity which we just saw on the last slide, right? That we’re currently experiencing. It wasn’t made for that. Much of our health problems are due to this fact. We are not made to handle this much social rejection, ostracism. Oh, they didn’t like my status. We’re not made for that. And it’s affecting us at a high rate. Guess what? Religion is perfect to combat that. It’s perfect to help us cope with that. However,
Chelsea Strayer
There’s also trade-offs. Because our brains and bodies are susceptible to human interaction, are susceptible to leadership and stable hierarchies, means some people are at the top and some people at the bottom. Some people have power, some don’t. There’s violence, there’s discrimination. You can become, you know, shamed, rejection, ostracism. You leaving a religion is not just an ideological shift. It’s a social, it’s detrimental to your social world, your worldview, your physical health, your mental stability. Okay, so there’s good, bad, and the ugly. It doesn’t mean there’s purposeful. It just means this is what it is, this is where it came from. Where are we going to go from here? And you guys are going to answer all that. Okay. Thanks.