Fig 1.
A graph of relationships among top predator (P: ant), specialist predator (C: parasitoid wasp), mutualist (F0: pollinating wasp) and exploiters (Fi (): non-pollinating wasps).
(A) empirical ecosystem work [37] and (B) an adaptive network framework in mutualist-exploiter-predator communities. is the foraging effort of P to Fj (
),
is the foraging effort of P to C and
. Solid lines indicate predation and each exploiter competes with the mutualist and other exploiters for resources generated by the mutualist; the width of solid lines represents the intensity of selective preferences of P to all prey.
Table 1.
Parameters used in the adaptive network model.
Fig 2.
Intermediate intensity of foraging adaptations generates chaos in the mutualist-exploiter-specialist predator-top predator (i.e., four-species MEST) community.
(A) bifurcation diagram; (B) Lyapunov exponent spectrum; (C) time series of population biomass (F1); (D) time series of foraging effort (θ1). Model parameters: r1 = 0.35, d1 = 0.05, u1 = 0.15, β10 = β01 = β = 0.18, g[0.05, 0.5] and other parameter values are presented in Table 1.
Fig 3.
Network structures and local stability change with the interspecific competition (β) and consumption rate (u1) in the four-species MEST community.
Stable coexistence of species is achieved when Re(λmax)<0. In each simulation case, the blue regions have higher stability than the red regions, and the empty white regions denote no solution to network modules. Key parameters of the four-species model: g = 0.28, u1[0, 0.3], β10 = β01 = β
[0, 0.18], r1 = 0.35 and other parameter values are presented in Table 1.
Fig 4.
The variable relationship between initial connectance and community stability (community persistence at steady state; mean standard deviation based on 20
20 replicates) in general MEST communities.
The different coloured regions represent different patterns of connectance-stability relationships. Key parameters of the full model: ri ~ U[0.3, 0.4], di = 0.05, ui = 0.15, βi0 = βji = β, and other parameter values are presented in Table 1.
Fig 5.
Comparison between theoretical prediction and empirical data analysis. (A, B) theoretical prediction presented in Fig 4; (C, D) empirical data analysis presented in the previous study [8], while the community stability is measured as 0.02/Re(λmax) for (C) freshwater communities and (D) marine communities. The fitted curve in (C) Stability = 0.89125-1.05279 × Connectance; in (D) Stability = 16.04436 × Connectance-16.60223 × Connectance2-3.54895.
Fig 6.
Foraging adaptation regulates the stability of the MEST community by changing positive or/and negative feedback loops. Sign ‘+’ indicates promotion and ‘-’ indicates inhibition. AF-adaptive foraging. (B, C) ‘+/-’ includes one case: promotion or inhibition; (D) ‘+(-)’ and ‘-(+)’ include two cases: promotion and inhibition, respectively.