install.packages(c('dplyr', 'ggplot2', 'readr', 'tidyr'))
download.file("https://datacarpentry.org/semester-biology/data/dinosaur_lengths.csv",
"dinosaur_lengths.csv")
download.file("https://datacarpentry.org/semester-biology/data/ramesh2010-macroplots.csv",
"ramesh2010-macroplots.csv")
download.file("https://ndownloader.figshare.com/files/5629536",
"TREE_SURVEYS.txt")
download.file("https://ndownloader.figshare.com/files/2292172",
"surveys.csv")
download.file("https://ndownloader.figshare.com/files/3299474",
"plots.csv")
download.file("https://ndownloader.figshare.com/files/3299483",
"species.csv")