Catch bond kinetics are instrumental to cohesion of fire ant rafts under load

Dynamic networks composed of constituents that break and reform bonds reversibly are ubiquitous in nature owing to their modular architectures that enable functions like energy dissipation, self-healing, and even activity. While bond breaking depends only on the current configuration of attachment in these networks, reattachment depends also on the proximity of constituents. Therefore, dynamic networks composed of macroscale constituents (not benefited by the secondary interactions cohering analogous networks composed of molecular-scale constituents) must rely on primary bonds for cohesion and self-repair. Toward understanding how such macroscale networks might adaptively achieve this, we explore the uniaxial tensile response of 2D rafts composed of interlinked fire ants (S. invicta). Through experiments and discrete numerical modeling, we find that ant rafts adaptively stabilize their bonded ant-to-ant interactions in response to tensile strains, indicating catch bond dynamics. Consequ..., , , # Catch bond kinetics are instrumental to cohesion of fire ant rafts under load

[https://doi.org/10.5061/dryad.8931zcrzf](https://doi.org/10.5061/dryad.8931zcrzf)

This respository contains the raw videos, data sets, and analysis codes used to generate the results of the manuscript titled above.

## Description of the data and file structure

Raw video footage used for analysis in this work is provided in MP4 format for top-views of the fire ant rafts (used to conduct image analysis) and MOV format for the side views of the springs (whose elongation was measured to estimate ant raft restistance forces). File naming convention is as follows:

* Top view footage of fire ant rafts loaded to uniaxial failure (at variable rates) and the corresponding side views of the springs used to estimate their resistance forces follow the filename formats *T**-Top-**.MP4* and *T**-Force-**.MOV*, respectively. Here, the sample number is an integer in the range [1,4] and the loading speed is a value in...