Motivations Underlying the Representation of Time in Family and Evolutionary Tree Diagrams

Activity: Talk or presentationInvited talk


This research discusses the representation of time within family and evolutionary tree diagrams to consider that the design of time is a fundamental choice in all diagrams, one that is motivated by a variety of needs. The discussion begins with a general model of the visual representation of time or tense which is developed from linguistics. It then considers the development of tree diagrams in the West from the earliest available copies in the eighth century to the present with examples coming from the domains of history, genealogy, religion, anthropology, genetics, evolution, and popular culture. Each example is discussed first in relation to its use and then by its composition using the visual variables of time’s direction, the primary reference point, scale, symbols, positions of symbols, and the size, color, tone and texture of any symbols and graphical elements. Overall, the choice for time’s direction of flow in a tree diagram depends upon how the diagram will be used, how much information needs to fit onto the page or screen, a culture’s patterns for writing and reading, aesthetics, linguistic metaphors, values, and the “ideal-real” continuum along the vertical dimension.

Mitchell, M. (2014). Fitting issues: The visual representation of time in family tree diagrams. Sign Systems Studies, 42(2/3), 241-280, and

Mitchell, M. (2016). More to reading images: Motivations underlying horizontal and vertical time-related graphics. The International Journal of Literacies, 23(4).
Period13 Sep 2022
Event titleDiagrams of Life & Evolution @ Diagrams 2022: 13th International Conference on the Theory and Application of Diagrams
Event typeConference
LocationRome, ItalyShow on map
Degree of RecognitionInternational