Tuesday, November 15, 2016

Did Our Ancestors Adapt to Detect Cheaters?

Cody Dillon-Owens, Nicholas Dillon, Mary Grove, Abbe Guarino, & Jasmine Agee



Have you ever wondered whether your friend will actually pay back that loan? Whether everyone on your backyard football team will play by the rules? Have you ever noticed that one shady looking guy across the poker table, you know, the one who looks like he's up to something but you don't know what? It turns out that wehumansmight actually have a specialized module dedicated toward detecting cheaters. 

It turns out that cooperation is indeed something necessary for survival, and cheaters have posed problems over our genetic history because they take advantage of this cooperation (to explore this idea furtherlook here). If you do someone a favor and they never repay you, you've just taken on all the cost for the benefit of someone else, with no benefit to yourself! Now that's not fair is it? 

As such, it would be evolutionarily beneficial if we could tell who might be one of these 'freeloaders'. This blog's goal is to see if this "cheater detection" exists and if it is an adaptation that led to increased survival for our wayward ancestorsIn order for something to be an "adaptation," it must have solved a specific problem for our ancestors. The two main questions this blog will try to answer are: 

1. What are the inputs that activate this detection mechanism? 
2. How does the mechanism actually help to detect cheaters? 

What activates it: In order to understand an adaptation we must first see hoa mechanism like cheater detection is triggered. For the cheater detection adaptation, the trigger is the desire for a reciprocal and fair exchange between two or more people 

How it helps: So how would detecting cheaters help in getting a fair exchange? If we can tell who cheaters are, we can avoid reciprocal altruistic exchanges with them and reduce losses, which would have aided in our ancestors' individual survivals. 

                                Inserting Picture...

The Evidence 

There is some controversy among psychologists about whether or not this cheater detection is just a part of our general abilities, or if it is a specific adaptation (but most of it says it is an adaptation). Let's first break down the evidence suggesting that it is an adaptation

Firstly, people tend to do better at correctly answering logic rule problems when these problems are put into cheater-detection contexts. 

Logic rule problems are problems in which you are given relevant information, an "If... Then" logic rule, and 4 different scenarios. The idea is that you must determine whether all the scenarios line up with logic rule. So... from the  relevant  information and this logic rule, you must pick the correct 2 out of 4 scenario options that will definitively reveal that they all follow (or do not follow) the logic rule. Heavy stuff right?  

This might be easier to visualize using the picture below. 

Say you had a rule that states: "If you have a vowel, there must be an even number on the other side". Which two cards would you pick? 

A lot of people choose 'A' and '2', even though this is incorrect. 'A' and '7' are the correct choices because the rule only says a vowel must have an even number. It would not matter if a consonant has an even or an odd number. However, if 'A' doesn't have an even number, or if '7' has a vowel on the other side, the rule is being broken.

Don't feel bad though, because this logic rule is in an abstract context, and we just suck at abstract logic. 

Now if we adapt this problem into a realistic social  problem  I think you might do a little better. 

Say you're a bartender, and you have to prevent anyone under 21 from drinking alcohol. Which of the cards below would you need to flip over to see if someone is committing underage drinking? 

This is a lot easier than the first problem, isn't it? You would check the person drinking 'Beer' and see what the '16' year old is drinking, because if someone under 21 has a beer or if the 16 year old has alcohol they are breaking the rule. 

Importantly, notice that the structure of the problem hasn't changed. You're still solving the same "If P, then Q" rule in both problems. But according to cheater detection theory, the reason that the second problem is so much easier is that it's presented in the context of a social contract where cheating is possible, and we have evolved mechanisms that are sensitive to possible cheating. The first problem just doesn't activate that relevant context. 

Now let's change this up a little bit. Say you live in a village. In this village there is a rule: "If a man eats cassava root, he must have a tattoo on his face". So, the only men that are allowed to eat cassava root have face tattoos. Which cards would you choose to make sure the rule is upheld


You probably picked 'eats cassava root' and 'no tattoo' right? Good job! This is the sort of cheater-detection evidence we're talking about. This also shows that familiarity doesn't count for this effect. Most people do just as well with this scenario as the underage drinking rule even though this scenario is totally unfamiliar.     

So the main focus here is that people get the most correct answers when these convoluted problems are put in a cheater-detection context, i.e., realistic social exchanges 

Varying Contexts 

The interesting part about this idea of the logic rule is that people are capable of identifying cheaters even when there is no perceived loss in a social exchange. People participating in these selection tasks seemed to focus mainly on not being cheated rather than focusing on the possible gains they would receive in a reciprocal social exchange. This demonstrates that our desire to avoid being cheated is a bigger focal point in an individual’s reasoning when it comes to obligations, social contract scenarios and especially rules of safety.  

The researchers’ findings suggest that detecting cheaters is a specific design feature in cooperation adaptations rather than a by chance product of the need to evade losses.  The idea of switching from logical to illogical choices based on relevance is known as a perspective change, which will be discussed next 

Switching Perspectives 

What if we presented one of these logic problems but specifically gave you a perspective and there was a possibility for each group to cheat the other? Consider this rule: “If an employee works on the weekend, then that person gets a day off during the week”. If you were an employee and had to decide whether a fellow employee had broken this rule, which cards would you turn over? If you were the employer and had to make the same decision, what cards would you flip over to check for cheating? 


If you were an employee you should check cards that would assure that your boss wasn’t screwing you over and not giving you days off that you deserve. The reverse is true if you were cued as an employer…you should check the cards that check that your employees aren’t taking advantage of this rule and lying about working the weekends to get a free day.  

What was actually found in a study that tested this situation (and other similar situations) was that the perspective that they were told to take almost always influenced the cards that the participants chose to flip over. This supports the existence of a cheater-detection mechanism because the subjects were flipping cards to see if they were being cheated on by the other party.  

It is important to note that all of these findings wouldn't matter if we didn't automatically go through this process in our heads. Fortunately it has been found an adaptation, like cheater detection, does come automatically which would provide evidence in favor of its existence. 

The Automacity of Cheater Detection 

People tend to automatically look for cheaters when the context primes them to do so. The automatic use of detecting cheaters is best seen in social exchanges in which reciprocity is understood between two parties. An example of this would be a classic if A then B scenario. Lets say that a friend of yours  borrows your car and its understood that they should refill the gas tank in exchange. More correct detections of cheaters occurred in this similar context.  These finding suggest that being able to detect cheaters is in fact automatic.   


"I Just Don't Like His Face." 

As it turns out, it seems that we can also tell who cheaters are by the way they look! 

Cheaters tend to have more aggressive or angry facial expressions compared to cooperators, and people are able to pick up on thisThese aggressive expressions also cause us to see them as less trustworthy. 

Researchers have also found that people tended to recognize the faces of cheaters more than the faces of cooperators. In other words, if someone cheats you, you're more likely to remember who they are (and what they did!) than someone who doesn't cheat you.  

Not only thisbut when we experience negative situations, such as interactions with aggressive-looking individuals, we tend to remember them more so than we would with  optimistically appearing people. This idea  aids in identifying an input that activates the cheater detection mechanism. Importantly, this cheater detection mechanism is an unconscious process, so these are not active thoughts in peoples' minds during these social situations.  

Let's bring our conversation to something that is a tad more relatable. If you have ever been in a social situation (and we are assuming you have), there are those flags that go off when you are around a threatening or perceptibly dangerous individual. Well, researchers identify one of these major "red flags" of cheaters: social status. We are defining social status here as how much money or “stuff” you have (or have access to).  

The notion here then is that a lower social status (when you don’t have a lot of money or “stuff”) is equated with being a cheater. And, unfortunately, there is evolutionary truth behind this shallowness. People of a lower social status (who have less “stuff”) need a way to obtain resources (to get more “stuff”), especially if they do not possess traits (such as strength) that can provide these resources. Cheating could then be an effective strategy to obtain these resources.   

The Naysayers 
Some researchers contend that humans do not have a specific cheater-detection module. In general, most of these researchers think that cheater-detection is just a function of a more general ability, rather than being a cognitive ability specifically designed to detect cheaters. 

Misunderstandings Hypothesis 

There have been a number of studies that have attempted to debunk the cheater-detection hypothesis. One study by Lawson at Arizona State University proposed a new hypothesis called the misunderstandings hypothesis. Primarily, this hypothesis suggests that wrong answers on logic problems do not occur as a result of them being out of a social contract context, but rather because people do not understand the problems being discussed (peep below for a reminder of the kind of problem we are talking about).  


This study went through a number of experiments…six to be exact. Lawson compared tasks that were social context specific to those that were not, tried to compare cheating detection to altruism detection, reworded the Wason task (the task in the picture above) etc. 

While Lawson ultimately concluded that cheater detection was contradicted by the study results, a careful examination reveals that among five out of the six studies, the true cheating scenarios still yielded the highest rates of accuracy (about 90%, vs. 40% or less in non-cheating problems). In the sixth study, the researcher used a different kind of logic problem than is typically used in cheater-detection studies, which made the problem significantly easier than normal. 

Thus, these findings do not really seem to contradict the cheater detection hypothesis. 

Relevance Theory 

The Lawson study is not the only one to challenge the cheater detection hypothsis. Carlisle and Shafir argued that we might just make use of general relevant information in the logic problems to answer them. They propose that our ability to correctly answer these questions relies on the content of the logic problem itself and not the context of the problem

Carlisle and Shafir were able to elicit about the same level of performance from 'non-cheater detection' problems as was displayed in the original cheater detection problems of the Gigerenzer & Hug study. In other words, people performed well regardless of context. Thus, it is possible that something other than the cheater detection hypothesis best explains these results, and this possibility should be further explored by proponents of cheater detection. 

El Fin 

What's the takeaway from this blog

While living cooperatively with others yields a great deal of benefits, it also carries risks. If a cheater "invades" an otherwise cooperative group, that person can exploit others with great benefits to themselves, and great costs to others. Much evidence suggests that in order to be resilient to such invaders, humans have evolved cheater detection adaptations to better operate within this social context.  

There is still research that needs to be conducted in order to rule out alternative explanations for what appears to be cheater-specific detection abilities, but there is a lot of evidence supporting this hypothesis so far. 

Either way, you should always keep your eye out at the poker table. And avoid those shady Craigslist deals. 



  1. To take an isolated person or incident and try to detect if they are cheating, or likely to cheat is extremely difficult. ON the other hand, if there is some type of historical value to compare against, then the ability to either project or identify one as a cheater is greatly enhanced. For the most part, people surround themselves with others of a similar value system. Honesty, and dishonesty are learned behaviors. My experience tells me that non cheaters are easier to detect. They'll look you straight in the eye, with a sincerity in their eye that will evoke a trust. Non cheaters don't have to remember what lie they told, or what pretense they need to uphold their charade, where as cheaters do. Past history and reputation go a long way to separating the cheaters from the non cheaters. Those with integrity and character will never be mistaken as a cheater, because cheating is not in their nature.

  2. I would agree with Victor's position that detecting a non-cheater is definitely easier and more consistent than looking for only a cheater (with the exception of a room full of cheaters where cheating is the "norm"). I had a conversation tonight with a parent of a kindergartener that is regularly being put in a "calm room" (isolation) after his behavior escalates through his education and discipline plan. The child has clearly manipulated the mother to this discipline being "unfair" or somehow "unjust" without considering the other children in the classroom from being given an opportunity to be in a classroom with no disruptions. He has learned to do what works for him; as is the case with "cheaters". We, as humans, know we have consequences for our actions and do weigh the risk/reward but will subconsciously lean towards what has worked for us in the past based on our experiences. Speeding, for example, is very common. If the speed limit is 55 MPH, traffic will almost inevitably cruise around 59 MPH because most people believe a police office won't mess with writing a ticket for 4 MPH over the limit. It's what works for us. In that scenario, habitual cheaters could be easily spotted by use of radar detectors, speed trap warning apps on their phones, or changes in their driving behavior. Someone that isn't habitually a cheater would likely slow down if they spotted an officer. The cheater, however, would be likely to maintain speed and have pre-calculated excuses for the speeding if they get caught. I enjoyed reading your thoughts on this project. My only critique is to be perhaps more specific on the type of cheating as every scenario for opportunities would have to have very specific means of detecting the cheating. Las Vegas casinos, for example, have expert behavioral psychologists always expanding and redefining suspicious behaviors and tricks/trades that professional cheaters have devised. Honesty and dishonesty are very interesting psychological concepts. I would love to know if you believe that justifications for the cheating should be considered (such as need for money/financial gain, just for fun to cheat a system, etc) impact these behaviors. Thanks again for a great research project.

  3. "If we can tell who cheaters are, we can avoid reciprocal altruistic exchanges with them and reduce losses, which would have aided in our ancestors' individual survivals." It's interesting to see the instinctual reason behind finding out cheaters, because you're taught growing up that cheating is vaguely just wrong and unfair, but you never think about it like that. But if you think about it, we all avoid cheaters now, or they are greatly punished in school because ultimately, they do not bring anything to the table, they just end up taking in an unfair way, while others used skill or just time and effort to aim for the same result, yet not receive it. In the case of gambling, that would result in the person who actually is skilled to lose because the unskilled person was a cheater. In the case of schooling, like an exam or something, the cheater being successful doesn't hurt or help anybody else, but it still would be unfair to the other students who did put in time and effort. - Paris Reinhard