Parts | Days | Selection | Search | Updates | Downloads | Help
BP: Fachverband Biologische Physik
BP 22: Computational Biophysics II
BP 22.7: Talk
Wednesday, March 14, 2018, 16:45–17:00, H 1058
How does reducible defense alter predator-prey dynamics? — •Tatjana Thiel, Andreas Brechtel, Adrian Brückner, Michael Heethoff, and Barbara Drossel — Technische Universität Darmstadt, Germany
In nature, numerous animal species use defense mechanisms like hardening or chemical secretions to defend against attacks of predators. However, there is yet no theoretical study of defensive mechanisms where protection is permanent, but diminished with attacks, which has been termed ''reducible defense''. This kind of defense mechanism is common among arthropods and is likely to change the dynamics and stability of the system.
We propose a predator-prey model where prey use a reducible defense mechanism (i.e. reservoir-based chemical defense). The prey excretes a certain amount of secretion upon attack and is therefore not consumable while it is armed. The predator has to attack often enough to disarm and consume prey, before the secretion is biosynthetically restored. We will discuss the behavior of our model under parameter changes and compare it to a conventional predator-prey system. We show that predator and prey can become considerably more abundant by taking reducible defense into account. Furthermore, we consider payoffs between fast replenishment of secretion and larger storage volume, and between investment in offspring vs investment in defense. For the latter, we find that prey should invest more in defense when resources are scarce, but completely in offspring when plenty of resources are available.