Table 2 (a) Heritabilities (h2) and maternal effect (c2) values for each treatment, (b) statistics of the fit to the animal model procedure and (c) significances computed by likelihood ratio tests

From: Heritability of progeny size in a terrestrial isopod: transgenerational environmental effects on a life history trait

Treatment

High carbohydrate

High protein

Control

Total (diet as a fixed effect)

h2±SE

0.08±0.36

0.61±0.39*

0.001±0.29

0.06±0.12

c2±SE

0.47±0.19**

0.11±0.17

0.38±0.15***

0.41±0.07***

e2±SE

0.46±0.19

0.28±0.24

0.62±0.16

0.53±0.07

V A

0.0023

0.0153

0.00001

0.0017

V C

0.0143

0.0028

0.0111

0.0118

V E

0.0141

0.0070

0.0180

0.015

V P

0.031

0.025

0.029

0.029

−2*LL

ACE

−1248.4

−1079.0

−1337.3

−3631.7

CE

−1248.3

−1076.2

−1337.3

−1631.4

AE

−1240.1

−1078.6

−1326.8

−1513.2

E

−1059.7

−975.6

−1209.8

−3210.4

Descriptive data

Sires

25

18

23

66

Dams

54

45

59

158

Offsprings

349

296

394

1039

Total animals

428

359

476

1263

Mean±SD (offspring, mm)

1.76±0.18

1.73±0.17

1.79±0.17

1.76±0.17

Min–Max (offspring, mm)

1.19–2.19

1.19–2.15

1.15–2.35

1.15–2.35

  1. h2=(direct) narrow-sense heritability; c2=common environmental and maternal proportion of total variance; e2=environmental proportion of total variance; SE=asymptotic standard error; VA=additive genetic variance; VC=common environmental and maternal variance; VE=residual variance; ACE model=full model including additive genetic variance+common environmental and maternal variance+environmental (residual) variance; CE=reduced model excluding additive genetic effects; AE=reduced model excluding common environmental and maternal variance; E=reduced model excluding both additive genetic effects and common environmental and maternal variance (assuming purely environmental effects). Twice the LL value approximates a χ2 distribution. Likelihood ratio tests (Lynch and Walsh, 1998) were performed to evaluate whether estimates were significantly different than zero, with degrees of freedom equal to the number of parameters dropped from the model. According to Shaw and Geyer (1997) (see also Dohm et al, 2001) this is a one-tailed test, where critical χ2 values are 2.706 and 4.605 with one and two degrees of freedom, respectively.
  2. *P<0.05.
  3. **P<0.01.
  4. ***P<0.001.
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