Table 2 Key concepts of CE and their application to EE (adapted from [1, 9, 15])

Culture

Socially transmitted information that can affect individual behaviors.

The focus is not on culture as a whole but on the information that is associated with social-ecological systems and is expressed in the relationships between people and biota [8].

Cultural traits

Cultural information that can be discretely or continuously transmitted.

EE can investigate and quantify cultural traits to generate hypotheses. An example of quantifiable cultural traits is therapeutic targets and the medicinal plants used to treat them (see [7]).

Variation

Heterogeneity of cultural traits within the group and between individuals.

EE can study the real and potential heterogeneity of cultural traits within a cultural domain (i.e., the redundancy (variety) of medicinal plants to treat a disease) [40].

Innovation

Introduction of a new cultural trait that results from different processes, such as the individual production of knowledge, guided variation, migration, or erroneous social transmission.

Innovation increases the heterogeneity of social-ecological systems, which is the basis for cultural evolution. For example, exotic species may be introduced into the social-ecological system by immigrants [48].

Individual production of knowledge

A type of innovation; a process by which an individual builds new information (innovations), particularly through experimentation; this new information may or may not be transmitted or become fixed within the culture.

EE can investigate if a cultural variation originates from the individual production of knowledge or another source of innovation. For example, local medical specialists can create new remedies by aggregating cultural traits within a local medical system (i.e., the cultural domain) [6].

Differential fitness

Characteristics that increase the appeal of learning a given cultural trait.

Some traits are more appealing or transmittable than others. Additionally, traits that confer adaptive advantages in social-ecological systems can be prioritized to be copied. For example, in a local medical system, information on the treatment of frequent diseases is more memorable than information on others [41].

Lamarckian inheritance

Modifications to the expression of a cultural trait (equivalent to a phenotype) are transmitted during social transmission.

This characteristic allows for variations that are generated through guided variation in social-ecological systems to be transmitted to other individuals.