When I was in Costa Rica two years ago to lay the groundwork for my ongoing study of religious ecology, the pastor who was showing me around had me stop along the road from Limón to Puerto Viejo to show me where the howler monkeys tended to hang out. I think we only saw one in the distance that day, but later I returned on my own to spend some time watching them. I was richly rewarded that trip when a group came right over my head & hung out (literally, of course) for an hour or so watching me watching them. But as I stumbled around, nearly tripping over giant spiders, I also became captivated with the immense lines of leafcutter ants & noticed how so many carried a piece of leaf that contained another ant as a rider. It was always only one ant rider, positioned almost as a backup or counterbalance. I had a terrible camera on that trip, so when we returned this past summer, we took another trip to the same spot to see the howlers. The howlers failed to show up in an great numbers this time, but I managed to get better photos of the leafcutters. I am still wondering why a leafcutter would carry a giant piece of leaf with a rider on it, which seems like it would make it more difficult. But I will have my opportunity to find out this week, when we host an ALLELE talk by one of the world’s foremost entymologists & the father of sociobiology, E.O. Wilson. In anticipation of this event, I’m reading his new book, The Social Conquest of Earth, & came across this quote about leafcutters, which just affirms that they are even more amazing than I could have possibly imagined (the theme, in fact, of another Wilson book I’ve been reading, The Creation):
Once she has been inseminated during her mating flight, she carries the sperm she receives in a little storage bag (the spermatheca) inside her abdomen. She can pay out one sperm at a time to fertilize her eggs, creating hundreds or thousands of workers over a period of years. Leafcutter ants hold the record: one queen can give birth to 150 million daughter workers during her life span of about a dozen years. Three to five million of these minions are alive at any given time–a size falling between the human populations of Latvia and Norway.