Empirical research on electronic communication (e-communication) behavior has been taking place since the 1970s, leading to the build up of a large body of evidence, which several researchers have tried to summarize through theories. These theories (for comprehensive reviews, see Carlson and Davis 1998; Teeni 2001) have emphasized the role that several factors have on behavior toward e-communication tools, notably: communication medium (e.g., degree of nonverbal cues available), collaborative task (e.g., level of equivocality and complexity), social environment (e.g., level of peer pressure for or against the use of a particular e-communication tool), and learned information processing schemas (e.g., degree of skill in connection with the use of a certain e-communication tool).
Surprisingly, though, virtually no e-communication theory looked at the role that biology or, more specifically, our biological communication apparatus, may have on behavior toward e-communication tools. The goal of this paper is to try to fill this gap by looking at how we evolved our biological communication apparatus, which seems to be designed primarily for face-to-face communication (i.e., synchronous and colocated communication employing facial expressions, body language, and oral speech), and providing a theory-based discussion of what should happen when we selectively suppress face-to-face communication elements (e.g., colocation, the ability to employ facial expressions, etc.) through e-communication technologies. Our discussion Kock/Evolution and Media Naturalness
374 2002 Twenty-Third International Conference on Information Systems involves the development of a new theoretical hypothesis, referred to here as the media naturalness hypothesis, which argues that, other things being equal, a decrease in the degree of naturalness of a communication medium (or its degree of similarity to the face-to-face medium) leads to the following effects in connection with a communication interaction: (1) increased cognitive effort, (2) increased communication ambiguity, and (3) decreased physiological arousal. We also discuss important implications for the selection, use, and deployment of e-communication tools in organizations, particularly in the context of business-toconsumer interactions.
2 HOMO SAPIENS EVOLUTION AND MEDIA NATURALNESS
All living species, including the human species, evolved through natural selection, a process in which random mutations are introduced in the genetic makeup of offspring, leading to traits that are selected based on their usefulness for survival and mating (Darwin, 1859; Mayr and Provine 1998). Genetic mutations that enhance the chances of survival and mating, in many cases only slightly (Dobzhansky 1971), slowly accumulate and spread through the members of a species, leading to the development of species-wide physical, behavioral, and cognitive traits over long periods of time. Virtually all evidence in connection with human evolution suggests that during over 99 percent of our evolutionary cycle we relied on colocated and synchronous forms of communication employing facial expressions, body language, and sounds (including speech, which uses a large variety of sound combinations) to exchange information and knowledge among ourselves (Boaz and Almquist 1997; Pinker 1994, 1997).
The evolutionary biology principle of repeated use argues that there is a correlation between the degree of evolutionary optimization of a particular set of organs used to perform a certain task by a species and the number of generations (or, generally speaking, the amount of time) in which those organs are repeatedly used to accomplish the task (Mayr 1976; Mayr and Provine 1998; Wilson 2000). Thus, it is plausible to conclude that, since our biological communication apparatus has been used for colocated and synchronous communication using facial expressions, body language, and sounds over such a long period of time, then...