Banca de DEFESA: EDUARDO GOMES DE ARAÚJO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : EDUARDO GOMES DE ARAÚJO
DATE: 26/05/2025
TIME: 10:00
LOCAL: DEINFO
TITLE:

Impact of prey evolution and spatial heterogeneity on the dynamics of a predator-prey system

 

KEY WORDS:

rey-predator; mutation; competition for resources; spatial heterogeneity.

 

PAGES: 127
BIG AREA: Ciências Exatas e da Terra
AREA: Probabilidade e Estatística
SUMMARY:

The mathematical study of the interaction between prey and predator populations began with the
research conducted by Lotka and Volterra. Since then, prey-predator systems have been modeled using a
wide range of mathematical and computational techniques. Through the use of these techniques, it is
possible to simulate the interactions between prey and predators to understand the behavior of an ecosystem and how this behavior spatially affects the system. In this context, we employ a computational
model that considers prey-predator interactions in a heterogeneous habitat, with resources distributed
according to a fractal landscape generated by fractional Brownian movement, which allows the regulation
of terrain roughness through the Hurst exponent, H. The computational model used in this study employs
a two-dimensional environment using the Von Neumann neighborhood, which enables an individual at a
given site to interact with its four closest neighbors. The prey species are defined by a set of half-
saturation constants for different resources, modeled by a Gaussian distribution, representing their
efficiency in utilizing each resource. The model considers prey survival, reproduction, and mutation, as
well as predator predation and reproduction. The probability of prey reproduction depends on resource
availability and is described by an adaptation of Monod’s equation, following Liebig’s Law of the Minimum.
The system is initially composed of a single prey species, and new species emerge through mutations,
occurring with a probability υ, simulated by alterations in the half-saturation constants inherited from the
parent. Based on the results obtained, the dynamics of prey and predator populations are strongly
influenced by the probability of predator reproduction (rp), the prey mutation rate (υ), and the
heterogeneity of resources represented by the landscape (H). For low predator reproduction rates (rp =
0.01), prey occupy most of the network, leading to predator extinction. With an increase in rp (rp = 0.1 and
rp = 0.2), we observe the coexistence of both species, but even higher values of rp result in successive
extinctions. Prey species diversity is higher under low predator reproduction rates and high mutation
rates, while more heterogeneous terrains (H 0) generally support fewer species. The species abundance→
distribution also reflects this dynamic, showing high diversity under high mutation and low predator
reproduction, but a concentration of a few dominant species as predator reproduction increases and
mutation rates decrease.

 

 

COMMITTEE MEMBERS:
Externo ao Programa - 2144133 - NATHAN LIMA PESSOA - nullExterno à Instituição - PEDRO HUGO DE FIGUEIREDO
Presidente - VIVIANE MORAES DE OLIVEIRA