Supplement 1. An R-script and data file for the analysis conducted in the main paper.

File List Data.txt (md5: 98f606cc561c67f3c31fffc54687162b)<br> CT_Method_(User_Version).r (md5: 4b9125ece816c25f69503000707f1031)<br> Description Data.txt – A data set containing species abundances for <i>Pseudo-nitzschia australis</i> and <i>Prorocentrum micans</i> along with surface water temperatures, collected at the Scripps Institute of Oceanography station for the time period 1930 to 1937. No column headers are given in the file for coding purposes, however the columns, in order, correspond to: the day number on which observations were made, the log-abundance for <i>Pseudo-nitzschia australis</i>, the log abundance for <i>Prorocentrum micans</i> and finally the surface temperature. CT_Method_(User_Version).r – R source code of approximately 475 lines (comments included) for implementation of the methodology introduced in the paper. The code is set to run the analysis presented in the paper. The R code should run so long as Data.txt is kept in the current R working directory. Comments in the script indicate, where necessary, what the applicable lines of code do and how they pertain to the main paper. MCMC output is automatically analyzed and figures are saved in .pdf format in the working directory. It is advised that an open source editor such as Tinn-R be used in order to aid readability of the code.