Drama in black, chartreuse, pink and yellow

Click for greater clarity.

On July 25, 2011, a year and a day ago, I went to the prairie restoration at Austin’s old Mueller Airport. At one point during a walk around the pond there, I sat down to photograph some flowers of sensitive briar, Mimosa roemeriana. Briars these plants surely are, with recurved prickles that have a knack for embedding themselves in the skin of people who handle them incautiously. And it isn’t only people’s skin that’s sensitive: touch the compound leaves of one of these low-growing plants, and watch the little leaflets fold shut within seconds.

But a drama other than the closing of leaflets caught my attention once I’d sat down. On the underside of this flower globe I noticed two tiny chartreuse caterpillars, and I saw that a couple of ants had noticed them, too. The ants ran up and down, often treading on and continuing over the little caterpillars, occasionally grabbing at them as if trying to pull them away. Perhaps the ants looked forward to a meal, or perhaps they were defending their territory. I don’t know enough about ant behavior to say, and although I watched and took pictures for a while, nothing conclusive happened. Eventually, say anticlimactically if you wish, I continued on my way.

UPDATE: See the explanatory comment below by Spider Joe Lapp.

© 2012 Steven Schwartzman