Table 1.
Fitness Estimates.
Figure 1.
Spatial distribution of host plants of bagworms, Thyridopteryx ephemeraeformis, sampled in Indiana, Kentucky, and Tennessee to determine multiple components of female fitness during the 2008 bagworm generation (Table 1). Latitude (x) significantly affected the proportion of mated females [logistic model with 110 sites, y = e (43.3−1.05 x)/(1+e (43.3–1.05 x)), χ = 393.46, P<0.0001], fecundity [linear model with 100 sites (excluding sites with none or <3 overwintered egg masses), y = 1698−36.0 x, r2 = 0.496, P<0.0001] and the proportion of overwintering survival [logistic model with 104 sites (excluding sites with <3 egg masses sampled), y = e (89.3−2.16 x)/(1+e (89.3−2.16 x)), χ = 104.41, P<0.0001).
Figure 2.
Spatial distribution of host plants of bagworms, Thyridopteryx ephemeraeformis, sampled in Indiana to determine multiple components of female fitness during the 2009 bagworm generation (Table 1). Latitude (x) significantly affected proportions of pupal survival [linear model with 50 sites, y = 4.33−0.086 x, r2 = 0.257, P = 0.0002] and of mated females [linear model with 50 sites, y = 12.2−0.29 x, r2 = 0.655, P<0.0001], as well as fecundity [linear model with 49 (excluding one site with no egg mass sampled), y = 2315−50.8 x, r2 = 0.305, P<0.0001].
Figure 3.
Spatial distribution of host plants of bagworms, Thyridopteryx ephemeraeformis, sampled in Indiana and south Michigan to determine the presence or absence of bagworms (table 3). For comparison, the effect of latitude (x) on female reproductive output (y, in mg eggs; see Table 1) is depicted in 2008 (y = 4059−96.1 x, r2 = 0.662, P<0.0001, N = 61 sites) and 2009 (y = 4612−110.0 x, r2 = 0.652, P<0.0001, N = 50 sites).
Table 2.
Source of variation.
Table 3.
Latitudinal distribution of bagworms.
Table 4.
Extinction of bagworm populations.