spider: Species identity and evolution is an R package developed by the Lincoln University molecular ecology lab group to do a range of analyses that various lab members wanted to run that were not yet implemented in R. In particular, the package provides functions for conducting sliding window analyses on DNA sequences, the calculation of identification efficacy of a library of reference DNA sequences, and the segregation of distance matrices into their inter- and intra-specific components.

The above are the main attractions, and the ones that we tend to write about when promoting it in places like the 4th International Barcode of Life Conference. There’s a bunch of other neat utilities in there also though. A couple of the ones that I particularly enjoy are tiporder(), which returns the tip labels in the order in which they appear on the tree; paa() which conducts population aggregate analysis on a dataset; and rosenberg() which calculates Rosenberg’s probability of monophyly for the nodes on a tree.

Spider is available on CRAN, and R-Forge, the latter providing opportunities to report bugs and to collaborate in the future development of the package should you desire to do so.