I have two figures, one phylogenetic tree generated with ggtree, and a map plot generated with ggmap. The two figures have points that I want to link with a line between the plots, like so:
However, all the previously asked questions I could find only covered linking points within the same plot, not across plots. Is there any way to do this?
Example code is here:
library(ggplot2)
library(ggmap)
library(ggtree)
tree <- rtree(5)
testdata <- structure(list(id = c("t1", "t3", "t5", "t4", "t2"), city = c("Oslo",
"Drammen", "Bergen", "Kristiansand", "Trondheim"), lat = c(59.9138688,
59.7440738, 60.3912628, 58.1599119, 63.4305149), lon = c(10.7522454,
10.2044565, 5.3220544, 8.0182064, 10.3950528)), class = "data.frame", row.names = c(NA,
-5L))
limits <- c(left = 3, bottom = 57, right = 32, top = 71.5)
norway_map <- get_stamenmap(bbox = limits, zoom = 6, maptype = "toner-lite")
ggtree(tree) %<+% testdata +
geom_tippoint(aes(fill = city),
pch = 21,
size = 3) +
theme(legend.position = "none") +
ggmap(norway_map) +
geom_point(data = testdata,
aes(x = lon,
y = lat,
fill = city),
pch = 21,
size = 3) +
theme(axis.text = element_blank(),
axis.title = element_blank())
Unfortunately, the ggmap requires access to google API services. Other maps can also be used if preferred.