Try
id, samples, stoneflies, mayflies, caddisflies, beetles, flies, detritus
2, 1, 25, 37, 6, 3, 4, 1
3, 2, 27, 18, 5, 6, 19, 1
4, 3, 26, 17, 4, 4, 11, 2
5, 4, 60, 43, 6, 4, 10, 2
6, 5, 52, 52, 8, 9, 34, 4
7, 6, 82, 82, 7, 6, 47, 7
8, 7, 86, 80, 8, 27, 56, 7
9, 8, 81, 88, 7, 6, 14, 8
10, 9, 91, 92, 16, 16, 76, 10
11, 10, 118, 103, 8, 6, 57, 12
then plot will yield
readr::read_csv("~/Desktop/grist.csv") -> dat
#> Parsed with column specification:
#> cols(
#> id = col_double(),
#> samples = col_double(),
#> stoneflies = col_double(),
#> mayflies = col_double(),
#> caddisflies = col_double(),
#> beetles = col_double(),
#> flies = col_double(),
#> detritus = col_double()
#> )
plot(dat)

Created on 2020-09-11 by the reprex package (v0.3.0)