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When archaeologists find Neandertal remains in Europe and Asia, they don’t find bones from huge groups. Neandertals never formed huge groups, as Homo Sapiens like you and I do. Usually, fossilized Neandertal remains reveal small kin groups – sometimes extended kin groups up to about 30. On the other hand, for thousands of generations, fossil records reveal that Homo Sapiens formed groups that included non-kin – and that seemed to reach about 150 individuals or so. And after the advent of agriculture, human groups can run into the hundreds of millions or even billions (think China!).
Neandertals aren’t quite as extinct as you might have thought a few minutes ago, by the way (see Hodgson, Bergey, & Disotell, 2010). Genetic evidence reveals that most of us (likely yourself included) have DNA overlap with ancient Neandertal genomes – probably with between 1-4% of your DNA matching our ancestral Neandertal cousins rather well – a result of ancient human/Neandertal hybridization incidents from thousands of years ago (see Hodson et al., 2010). This is something I am studying with my students as part of the New Paltz Neandert Project. But I digress …
By all relevant fossil record accounts, Neandertal skulls likely housed brains that were larger than our modern Homo Sapien brains. They probably were no less intelligent than we are. However, the main difference between us and them (other than the fact that they get disproportionate exposure in Geico commercials …) pertains to the fact that at some point, our Homo Sapien ancestors developed psychological and social strategies that led to the creation of social groups that extended well beyond kin lines. As smart and cool as they were, the Neandertals never seemed to evolve this capacity to have extended social groups comprised of many individuals working toward common goals in synchrony.
Achievements Associated with Large Homo Sapien Groups
You don’t have to think too hard to come up with examples of how the tendency to form large groups can lead to great outcomes. A small family of individuals – no matter how crafty – could have never built the pyramids of Egypt. Or the Colosseum of Rome. Or the Great Wall of China. Or the George Washington Bridge.
A group of 10 genius Neandertals never ever could have, by themselves, put a Neandertal on the moon. No matter how awesome that would have been!
The tendency for Homo Sapiens to form large social groups that extend beyond kin lines alone is, in an important way, a key to understanding human uniqueness within the animal world (see Bingham and Souza, 2009).
Formation of Social Groups and Human Religion
The tendency for modern Homo Sapiens to form large social groups beyond kin lines bears strongly on the fact that humans are the churchgoing ape (see Geher, 2014). And while there is much variability from one religion to another in terms of specific practices, all religions (see Wilson, 2002) seem to cultivate this uniquely human tendency to form psychologically created groups that extend beyond kin lines.
One of the main psychological antecedents to religious thinking is what we call “ingroup/outgroup” reasoning. People around the globe are highly predisposed to automatically put people into two basic groups – my group – or not my group (see Billig & Tajfel, 1973). This mentality helps benefit religious groups (and the individuals within them) because it keeps members of the same group positively predisposed toward one another. Our Neandertal cousins likely did not have this same tendency to form psychologically created groups beyond kin lines that we often connect with religion.
However, ingroup/outgroup reasoning is not all peaches and cream. This kind of reasoning seems to predispose members of one group to see members of other groups (outgroups) in less positive terms. This reasoning also corresponds to the tendency for people to see members of outgroups as sort of “all the same” – we call this tendency outgroup homogeneity – and we often can’t help it! It is hard for us to see members of groups that are very different from our own in the same positive ways that we often see members of our own groups. This all seems to be part of the basic social psychological architecture that evolved along with origins of religious belief in early Homo Sapiens. Ingroup/Outgroup thinking and the tendency to see all outgroup members as similar to one another are foundational features of human social psychology – like it or not, it’s part of how we think.
In his famous book, Cat’s Cradle (1963), Kurt Vonnegut explicated these concepts well. Particularly, he came up with the idea of a granfalloon – which essentially is an artificially created group based on some meaningless characteristic which binds people together psychologically. So in Cat’s Cradle, for instance, when strangers on a plane trip to a tropical island find out that that they happen to both be from Indiana, they are suddenly bonded – extolling the virtues of being a Hoosier and progressing as if they now can trust one another for life. Vonnegut called it granfalloon – social psychologists call it ingroup/outgroup reasoning – it’s the same thing – it’s the way that we automatically form groups based on minimal criteria and become predisposed toward members of these groups no matter how silly they are (sorry Hoosier Nation!).
And it’s likely the case that Neandertals did not form granfalloons. They did not form groups based on artificial criteria. They did not form religious groups that were encompassing of others beyond their kin. And they were not part of the Hoosier nation.
Ingroup/Outgroup Reasoning: The Good and the Bad
Like many evolved features of human psychology, ingroup/outgroup reasoning comes with some good and some bad. Without the capacity to form large-scale, coordinated groups – thanks to ingroup reasoning – we would not have the Eifel Tower, the internet, or Ben and Jerry’s ice cream. All of these great wonders of the modern world were created by large groups of humans working together toward a common goal. Large groups of largely unrelated individuals who saw themselves as part of something bigger and as connected to one another. This is the primary benefit to our world for which we can thank our evolved ingroup/outgroup reasoning.
But ingroup/outgroup reasoning has a dark side. And the long history of war that goes thousands of generations deep in our species betrays this fact. As philosopher David Livingstone Smith (2008) shows, war is something of a human constant – and the tendency for warring individuals to devalue members of the other side – seeing such outgroup members as vermin or as non-human in some other way – is remarkably common in the social psychology of warfare. Seeing your enemies as non-human makes it much easier to kill them. And we can thank our ingroup/outgroup reasoning for this as well.
What Neandertal Research Can Tell us About Being Human
In sum, I argue here that studying the nature of our ancient cousins, the Neandertals, provides an opportunity for us to better understand ourselves. Homo Sapiens differ from our ancestral cousins largely in terms of the fact that we create large social groups that extend well beyond kin lines. And this group construction is done in connection with strong ingroup/outgroup reasoning which seems strongly embedded in how we operate. And it seems that the Neandertals, who were intelligent in their own right, did not engage in such non-kin group formation.
Having a psychology that is strongly based on ingroup/outgroup reasoning has both benefits and costs. Benefits include the fact that, unlike our Neandertal cousins, we are able to create large groups of individuals - capable of achieving extraordinary feats, such as putting a man on the moon. But this benefit comes at a cost. This same ingroup/outgroup feature of our psychology underlies the darkest times of human history – with all human warfare deeply and importantly rooted in our basic tendency to engage in us-versus-them thinking.
I hope that having people better understand the deep roots of ingroup/outgroup reasoning – and how this feature of human psychology relates to the unique evolutionary history of Homo Sapiens – can help people be mindful of this largely automatic tendency that touches so much of our psychology and our day-to-day lives (sometimes for better, and sometimes for worse).
The New Paltz Neandertal Project
And by the way, the New Paltz Evolutionary Psychology lab is currently collecting data bearing on Neandertal psychology by studying those who have had their personal genomes mapped (and who have access to their “percent Neandertal overlap” data). Have you had your DNA mapped – and do you want to contribute to our understanding of Neandertal and Homo Sapien psychology by completing a survey for the New Paltz Neandertal Project? Please follow this link to find the formal survey introduction and link!
References and Related Reading/Links
Billig, M., & Tajfel, H. (1973). Social categorization and similarity in intergroup behaviour. European Journal of Social Psychology, 3, 27–52.
Bingham, P. M., & Souza, J. (2009). Death from a distance and the birth of a humane universe. Lexington, KY: BookSurge Publishing.
Geher, G. (2014). Evolutionary Psychology 101. New York: Springer.
Hodgson, J. A, Bergey, C. M., & Disotell, T. R. (2010). Neanderthal genome: the ins and outs of African genetic diversity. Current Biology 20, 517-519.
Smith, D. L. (2008). The most dangerous animal. New York: St. Martin’s Griffin.
Vonnegut, K. (1963). Cat’s Cradle. New York: Dell.
Wilson, D. S. (2002). Darwin’s Cathedral: Evolution, Religion and the Nature of Society. Chicago: University of Chicago Press.
