were obtained using the Elefan I Fisat II program, version 1.2.2. The growth rate of 0.07 mm/day, proposed by Nitchals ( 2014 ) for other species of gammarids under similar conditions to calculate an approximation of the intrinsicgrowthrate, was used to calculate the generation time. To investigate
Infectious disease influences the dynamics of host populations and the structure of species communities via impacts on host demography. Species that share infectious diseases are well-known to interact indirectly through the process of apparent competition, but there has been little attention given to the role of vectors in these indirect interactions. Here we explore how vector-borne disease and host-vector interactions can drive apparent competitive interactions. We show that different facets of the ecology associated with vector-host-host interactions affect the structure of the three-species assemblage. Crucially, the patterns associated with invasion of alternative hosts, the spread of the infectious disease by the vector, and the dynamics of the community interactions are influenced by the mode of transmission. We highlight the role of alternative hosts on disease amplification, dilution and magnification and discuss the results with reference to recent developments in apparent competition and community structure.
‘intrinsicgrowthrate,’ which does not depend on any interactions among different items but solely on linguistic properties of 16 . Crucially, this rate is assumed to depend on the item’s formal substance 17 so the intrinsicgrowthrate 18 is formulated as a function of 19 : 20 , 21 . The rate is defined
a certain habitat, and r the intrinsicgrowthrate, i.e. , the rate of population increase without external limitations. In addition, the inflection point (
_mid (in weeks)
K ), the doubling time (DT), i.e. , the average time (weeks) needed to double the population
space for growth than smaller hosts. Secondly, the intrinsicgrowthrates of fish in the host population are also likely to be of importance. Al- though interpopulation variation in intrinsicgrowthrates in sticklebacks has been documented (Wright et al., 2004), the implications for patterns of host
estimated using this routine: L t D L 1 f 1 ¡ e ¡ K . t ¡ t 0 / g where L t is the length at age t, L 1 is the asymptotic length, K is the intrinsicgrowthrate (curvature parameter) and t 0 is the computed age at length zero.
1126 NATÁLIA DIAS & MARTIN SPRUNG Growth curves of females and males were
stickleback ( Gasterosteus aculeatus ) in Llyn Frongoch an upland Welsh lake. — Freshwater Biol. 14, p. 335-346. Al-Shamma’a, A.A.M.-H. (1986). The feeding ecology of fish in Llyn Frongoch. — Ph.D. Thesis, University of Wales, p. 118. Arendt, J.D. (1997). Adaptive intrinsicgrowthrates: An integration across
¡ [ K D.t ¡ t 0 / C C.K D= 2 ¼/ sin 2 ¼.t ¡ t s / ] ² 1 =D Where: L t D length of the organism at a given moment t ; L 1 D maximum possible length of the organism; K D intrinsicgrowthrate; t 0 D instant when the organism would have a length equal to zero; t s D time interval between start of growth
( 2006 ).
Evolution of intrinsicgrowthrate: metabolic costs drive trade-offs between growth and swimming performance in Menidia menidia . —
1269 - 1278 .
( 2012 ).