Latitude / longitude will vary slightly depending on the coordinate system (CS) used to collect the points (e.g. a WGS84 point is approx. 1m separated from the same coordinates in NAD83). However, non-GIS specialists collecting GPS-unit field data often provide coordinates with no mention of the datum (e.g. 44.247078, -76.572635). It is as if some standard CS is being assumed, and in my experience that usually turns out to be WGS84. Do others agree or have thoughts on this?

@Waterman "The most common global CRS in latitude and longitude is WGS84 (used by the GPS satellite navigation system) with the following CRS string "+init=epsg:4326" as identifier." cran.r-project.org/web/packages/eRTG3D/vignettes/….