Miniature Archaeology
Jan. 28th, 2008 05:23 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
rebeccmeisterThis semester, my awesome undergraduates and I have devised a scheme to keep ourselves on track with the research we hope to accomplish. My objective for this week was to complete some measurements on samples of leafcutter ant trash heaps, and I was moderately successful today. But I thought you'd probably be amused to hear about what this work entails.
First, I should explain how leafcutter ant colonies work, from the perspective of materials management. The ants harvest leaves (hence the name leafcutter), and bring these leafy bits back to their colony. Once they bring the leaves underground, they are carefully licked clean and chewed up into tiny fragments. These freshly cleaned fragments are then attached to the ants' fungus garden, and oftentimes new strands of fungus are carefully planted on the fresh material. The growing fungus is used as food, mostly for the developing young.
Eventually, the fungus uses up all of the accessible nutrients in the leaf fragments, and grows old and dies. At this point, the ants carefully trim out the dead bits, and carry them off for disposal in a trash heap. If they were to leave these bits in the nest, they would attract unhelpful, weedy fungus species. Colonies vary in their garbage management systems: some opt for open-air trash piles, while others create underground dump chambers.
In the laboratory, the ants can't be too choosy about where to leave their trash. The species that I work with generally throws out its garbage in piles in external foraging chambers, which is nice for me because then it's fairly easy to collect. The only trouble is that the ants don't sort their garbage by type: dead ant bodies and minuscule fragments of plaster get incorporated with the used-up fungus. I'm only interested in the used fungus for the moment, so I've had to develop methods to get only what I want. My solution so far has been to develop a miniature sieve to sift out much of the plaster bits, and then to go through the remnants carefully by hand with a dissecting needle and paintbrush, separating chunks of plaster and dead ant bodies from the old fungus bits. Fortunately, a dissecting microscope has aided me considerably with the process, but altogether it's painstaking work. I can only hope that the ant trash will be as informative to my questions as human trash is informative to archaeologists.
First, I should explain how leafcutter ant colonies work, from the perspective of materials management. The ants harvest leaves (hence the name leafcutter), and bring these leafy bits back to their colony. Once they bring the leaves underground, they are carefully licked clean and chewed up into tiny fragments. These freshly cleaned fragments are then attached to the ants' fungus garden, and oftentimes new strands of fungus are carefully planted on the fresh material. The growing fungus is used as food, mostly for the developing young.
Eventually, the fungus uses up all of the accessible nutrients in the leaf fragments, and grows old and dies. At this point, the ants carefully trim out the dead bits, and carry them off for disposal in a trash heap. If they were to leave these bits in the nest, they would attract unhelpful, weedy fungus species. Colonies vary in their garbage management systems: some opt for open-air trash piles, while others create underground dump chambers.
In the laboratory, the ants can't be too choosy about where to leave their trash. The species that I work with generally throws out its garbage in piles in external foraging chambers, which is nice for me because then it's fairly easy to collect. The only trouble is that the ants don't sort their garbage by type: dead ant bodies and minuscule fragments of plaster get incorporated with the used-up fungus. I'm only interested in the used fungus for the moment, so I've had to develop methods to get only what I want. My solution so far has been to develop a miniature sieve to sift out much of the plaster bits, and then to go through the remnants carefully by hand with a dissecting needle and paintbrush, separating chunks of plaster and dead ant bodies from the old fungus bits. Fortunately, a dissecting microscope has aided me considerably with the process, but altogether it's painstaking work. I can only hope that the ant trash will be as informative to my questions as human trash is informative to archaeologists.
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Date: 2008-01-29 01:17 am (UTC)no subject
Date: 2008-01-29 04:49 am (UTC)no subject
Date: 2008-01-29 01:49 pm (UTC)no subject
Date: 2008-01-30 03:34 pm (UTC)no subject
Date: 2008-01-31 02:23 am (UTC)no subject
Date: 2008-01-29 08:40 pm (UTC)totally fascincating. I love how neatly efficient it all is.
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Date: 2008-01-30 03:33 pm (UTC)no subject
Date: 2008-01-30 04:04 am (UTC)no subject
Date: 2008-01-30 03:33 pm (UTC)That could be pretty interesting. I could see the starting point being, do different trash items have different chemical signals? We know that there are particular pheromones that appear on the body of dead ants (if you paint them on living ants, other ants will carry them out to the trash heap). But how do the ants decide when to trim away bits of the fungus garden? And what about the addition of plaster to the trash heap?
Before this gets too distracting, you need to have your own project in line!