An evolved psychological adaptation (EPA for short) is a species-typical behavioral or cognitive
trait which has been shaped by the process of natural selection, because of genetic fitness
benefits it conferred to its bearers over the course of evolutionary time. For example,
organisms which need to consume water in order to survive may have a set of EPAs which causes
them to crave water, approach water sources, drink water, and (possibly) experience the
ingestion of water as pleasurable or as relieving an aversive sensation we might call
While there is debate among the scientific community on the role of modularity in our
psychological development, PsychTable uses the term EPA to refer to psychological adaptations
which may or not be modular. This is to ensure the participation of behavioral scientists from a
wide variety of theoretical stances. We especially welcome users who submit concrete
multidisciplinary evidence for each EPA.
The defining criterion of an EPA is that it develops similarly in all individuals of a species
given a typical developmental environment (Barrett & Kurzban, 2004). Accordingly, it should
be noted that the definition of an EPA does not include behavioral inflexibility in the face of
personal experience, nor does it specify that EPAs are unchanging throughout the life course. On
the contrary, EPAs should be expected to display high levels of responsiveness and variability
to different environmental inputs as well as varying expression over different stages of the
A visual table will display the most strongly supported EPAs (calculated based on a number of
factors involving the ratings of each citation) using a classification scheme based upon the
consensus of expert evolutionary and behavioral scientists. This table will allow easy reference
of the basic properties of EPAs and their relationship to each other (including their
hierarchical neurocognitive structure).
Proposed EPAs will be collected in a searchable and browseable database. The profile of each EPA
compiles information on the purported functions, neurobiological underpinnings, eliciting and
output systems, etc. of that EPA, as well as a collection of user-submitted citations that
support and challenge its existence.
Curators rate each citation’s ability to support/challenge the EPA along eight different lines of
evidence (theoretical, psychological, physiological, genetic, phylogenetic, medical,
cross-cultural, and hunter-gatherer). The ratings of each citation will be calculated into a
series of scores that will represent how strongly each EPA is supported in the scientific
You can join the PsychTable community! Vetted researchers and practitioners can add and edit EPAs
in the system and contribute citations for and against each EPA. Level of editorial access is
dependent upon user’s experience and status. Anyone can request to become a curator or
contributor. For extended curation privileges, you need to supply credentials. A PsychTable team
member will then review your request.
Contributing to PsychTable can be as small or as big a commitment as you wish. It only takes a
minute to upload or rate a citation, and you can upload as few or as many as you want at any
For in-depth information on PsychTable, please read
article by Balachandran and Glass, published in the journal
Evolution: Education and Outreach and our
newest article, published in the Politics and Life Sciences journal. Niruban
Balachandran's 2011 article, "A Proposed Taxonomy of Human Evolved Psychological Adaptations," which
appeared in the Journal of Social, Cultural, and
Evolutionary Psychology (now Evolutionary Behavioral
Sciences) was the original inspiration for PsychTable.org. Click
to read the article.
PsychTable benefits the scientific research community in three main ways: Firstly, by providing a
system to aggregate evidence for and against particular EPAs, PsychTable allows researchers in
the behavioral sciences to quickly reference the available support for any given purported EPA;
at a glance, researchers can see how much research has been done to support or challenge their
EPA of interest and whether it is firmly supported, lacking in empirical data, or somewhere in
Secondly, PsychTable provides a system to categorize the EPAs that are strongly supported. Through a dynamic and ever-improving taxonomic scheme, PsychTable provides a service to the evolutionary behavioral sciences by centrally displaying and organizing the current state of knowledge in the field. Scientists can now reference a single, authoritative resource to look up EPAs, rather than wading through the balkanized literature and risk missing important data or findings.
Lastly, in classifying and evaluating the evidence for EPAs, scientists will inevitably encounter gaps in their knowledge which will allow them to develop action plans and to lead new research directions to clarify our current knowledge of EPAs which have not been discovered or investigated yet.