animate_paths           animate paths
covariate_interp        Synchronous interpolation of covariate using
                        either GAM (same as paths) or piece-wise
                        constant if covariate is a factor
gam_interp              GAM interpolation using 'mgcv:gam()'.
network_interp          Synchronous interpolation of network using
                        piece-wise constant interpolation
paths_gam_interp        Synchronous GAM interpolation of all paths
plot.paths_animation    Plot animation path interpolation
vultures                GPS locations of turkey vultures.
