With ggtree (Yu et al. 2017), it is very easy to create phylomoji. Emoji is internally supported by ggtree.

Use emoji in taxa labels

library(ggtree)
tree_text <- "(((((cow, (whale, dolphin)), (pig2, boar)), camel), fish), seedling);"
x <- read.tree(text=tree_text)
ggtree(x, linetype="dashed", color='firebrick') +
    xlim(NA, 7) + ylim(NA, 8.5) +
    geom_tiplab(aes(color=label), parse='emoji', size=14, vjust=0.25) +
    labs(title="phylomoji", caption="powered by ggtree + emojifont")

p <- ggtree(x, layout='circular') +
    geom_tiplab2(aes(color=label), parse='emoji', size=12, vjust=0.25)
print(p)

open_tree(p, angle=200)

open_tree(p, angle=60) %>% rotate_tree(-75)

Labeling clades using emoji

set.seed(123)
tr <- rtree(30)
ggtree(tr) + xlim(NA, 5) +
    geom_cladelabel(node=41, label="chicken", parse="emoji",
                    fontsize=12, align=TRUE, color="firebrick") +
    geom_cladelabel(node=51, label="duck", parse="emoji",
                    fontsize=12, align=TRUE, color="steelblue") +
    geom_cladelabel(node=32, label="family", parse="emoji",
                    fontsize=12, align=TRUE, color="darkkhaki")

Apple Color Emoji

Although R’s graphical devices don’t support AppleColorEmoji font, it’s still possible to use it. We can export the plot to svg file and render it in Safari.

library(ggimage)
library(gridSVG)
p <-  ggtree(x, size=2) + geom_tiplab(size=20, parse='emoji') +
    xlim(NA, 7) + ylim(NA, 8.5) +
    geom_phylopic(image="79ad5f09-cf21-4c89-8e7d-0c82a00ce728",
                  color="firebrick", alpha = .3, size=Inf)

p
ps = grid.export("emoji.svg", addClass=T)

Further reading

Please visit ggtree homepage, https://guangchuangyu.github.io/ggtree, to find out more.

References

Yu, Guangchuang, David Smith, Huachen Zhu, Yi Guan, and Tommy Tsan-Yuk Lam. 2017. “Ggtree: An R Package for Visualization and Annotation of Phylogenetic Trees with Their Covariates and Other Associated Data.” Methods in Ecology and Evolution 8 (1): 28–36. doi:10.¹¹¹¹⁄₂₀₄₁-210X.12628.