I am amusing myself with several little experiments; I have now got a little weed garden & am marking each seedling as it appears, to see at what time of life they suffer most.–
Letter to Joseph Hooker
21 March 1857
A few years ago, I was talking with one of my professors. We’d recently been at a seminar where a National Academy of Sciences member had presented some research. The research in question drew a number of good conclusions about the role of seawater chemistry on the history of life using an experimental setup that featured plastic cups arranged on cafeteria trays. The professor commented that the ability to design a “dinky little experiment” that could shed real light on enormously broad questions was the mark of the truly great scientists.
Over the summer, that comment popped back into my mind as I stood looking at a tiny patch of fenced-off ground in the middle of a bit of lawn.
I was on the grounds of Down House, looking at a recreation of Charles Darwin’s weed garden. It’s a small (six square foot) patch of ground. Darwin cleared the ground down to the dirt, watched, and waited. The ground was recolonized by weeds, each of which he marked and observed.
Seedlings, also, are destroyed in vast numbers by various enemies; for instance, on a piece of ground three feet long and two wide, dug and cleared, and where there could be no choking from other plants, I marked all the seedling of our native weeds as they came up, and out of the 357 no less than 295 were destroyed, chiefly by slugs and insects.
On the Origin of Species
It’s hard to imagine a dinkier experiment. One small, cleared patch of ground in the middle of the lawn, observed on a daily basis over a period of several months. But the conclusions from this experiment – particularly when combined with quite a few other dinky little data sets – are very revealing: many more organisms are born than survive to reproduce.