library(sp)
library(raster)

# Make 2 objects
caribou1 <- SpatialPoints(cbind(x = stats::runif(10, -50, 50),
                                y = stats::runif(10, -50, 50)))
caribou2 <- SpatialPoints(cbind(x = stats::runif(10, -50, 50),
                                y = stats::runif(10, -50, 50)))

caribouTraj <- makeLines(caribou1, caribou2)

clearPlot()
Plot(caribouTraj, length = 0.1)

# or  to a previous Plot
files <- dir(system.file("maps", package = "quickPlot"), full.names = TRUE, pattern = "tif")
maps <- lapply(files, raster)
names(maps) <- lapply(maps, names)

caribouTraj <- makeLines(caribou1, caribou2)

clearPlot()
Plot(maps$DEM)
Plot(caribouTraj, addTo = "maps$DEM", length = 0.1)

clearPlot()
