Insects at Cosyne: Insights into neural computations from observing ants
March 7, 2013
This past week, some lab members and I attended the Cosyne meeting in Salt Lake City. We heard emerging work about cue combination of spatiotemporal frequencies from Alan Stocker’s lab as well as a new perspective on LIP neurons from the labs of Alex Huk and Jonathan Pillow.
On the last day, we heard a fascinating talk by Deborah Gordon, an ecologist from Stanford, who studies ants. Dr Gordon has uncovered the signals that ants use when they make decisions about whether to go and forage for food. This decision is critical: if ants forage when conditions are poor, they dehydrate themselves and end up with little to show for their efforts. But by paying close attention to olfactory cues from co-foragers as they return, ants can make an informed choice about whether to look for food. The above image shows trajectories of ants in the lab: each line shows the path of a single ant as she wanders around, encounters colony-mates and adjusts her path accordingly. By automating the process of ant tracking, Dr. Gordon can simultaneously monitor the position of many animals and make broad conclusions about what they do.
Dr. Gordon drew an interesting parallel between ant behavior and neural transmission. She likened the pool of at-the-ready foraging ants to the readily releasable pool of synaptic vesicles that sit at the synapse. Just as the neuron integrates calcium over time, the ants integrate olfactory signals from other ants. And just as the neuron will spike when enough calcium is accumulated, the ant colony will “spike” out ants when enough signal from returning foragers is accumulated.
Many of us are familiar with seeing similar evolutionary strategies played out in different species, but this is something more. Here, it seems that there is a similar mechanism operating at very different levels: the level of the whole ant colony and the level of an individual, tiny synapse within one organ within one individual animal.