“…This has been generalised in numerous investigations, for example in off-lattice models (Lipkova et al, 2011), whereby the framework at the individual level does not rely upon a discretisation of space and/or time, as well as the incorporation of numerous physical and biological features. Examples in this popular field (Chowdhury et al, 2005;Othmer and Stevens, 1997;Hillen and Othmer, 2000;Deroulers et al, 2009) include the consideration of exclusion processes (Landman and Fernando, 2011), motility biases such as chemotaxis (Hillen and Painter, 2009), competing cell populations (Penington et al, 2011), contact interactions (Lushnikov et al, 2008;Painter and Sherratt, 2003) and cell-cell adhesions (Stein et al, 2007).…”