The folder for each species contains a project file (.mxd) plus three or four shapefiles. Each of the latter consists of four separate files with identical names but different extensions (.shp, .shx, .dbf, .shp [XML]). The shapefiles are as follows:
Elements (polygon): the skeletal template itself, with each element or element portion as a separate feature.
Details (polyline): a purely aesthetic shapefile.
Outline (polyline): a rough sketch of the living animal, around the skeleton.
Background (polygon): a single polygon feature forming a backdrop to the template. This can be useful for distinguishing missing data from null values.