One phenomenon that has often puzzled computer science and information systems researchers over the years, particularly researchers interested in e-collaboration issues, is the high importance of having an audio channel for communication in the context of e-collaborative tasks (Graetz et al., 1998; Kock, 2004; Kock & DeLuca, 2007; Wainfan & Davis, 2004). Whenever audio is available (e.g., teleconferencing, telephone conference calls, face-to-face meetings), tasks seem to be performed more easily and with fewer misunderstandings. Moreover, adding video to an already present audio channel typically adds little to the e-collaboration medium’s ability to support group tasks (Burke & Aytes, 2001). While this is not a universal phenomenon (see, e.g., Daly-Jones et al., 1998; Baker, 2002), its frequent appearance in the empirical research literature merits a more robust theoretical analysis.
An evolutionary explanation of the importance of oral speech is discussed here. It is argued that the high importance of oral speech is restricted to knowledge-intensive tasks. The reason for that, which is advanced in more detail in the subsequent sections, is that oral speech evolved among our hominid ancestors as a costly trait to enable efficient and effective knowledge communication. As a costly trait, oral speech is analogous to the large train used by male peacocks to attract mates (often incorrectly called the peacock’s tail). That is, like the male peacock’s train, oral speech is: (a) a survival handicap that only evolved because of its strong indirect effect on reproductive success, which counteracts its negative effect on survival; and (b) particularly important in the context of the task for which it evolved, namely communication of knowledge. Finally, it is argued here that even in knowledge-intensive tasks, the negative effect caused by suppression of oral speech may be countered by compensatory adaptation, whereby individuals adapt their communicative behavior to overcome the limitations posed by the suppression of oral speech.