Table 4 Effects of female kinship and female body length on female reproduction.

From: Kinship reduces alloparental care in cooperative cichlids where helpers pay-to-stay

 

Wald χ 2

Coefficient±s.e.

P

Dominant female number of clutches produced (N=68)

 Intercept

3

−0.491±0.290

0.09

 Duration

33.9

0.0090±0.0015

<0.001

 Female body size

0.38

 

0.54

 Kinship

0.005

 

0.95

Dominant female clutch size (N=40, n=128)

 Intercept

27.3

2.340±0.448

<0.001

 Female body size

23.4

0.036±0.007

<0.001

 Kinship

0.6

 

0.44

Dominant female egg mass (N=39, n=123)

 Intercept

78.7

0.355±0.040

<0.001

 Female body size

3.7

0.0016±0.0008

0.054

 Kinship

2.7

 

0.10

Subordinate female number of clutches produced (N=68)

 Intercept

16

−4.08±1.022

<0.001

 Duration

17.5

0.0104±0.0025

<0.001

 Female body size

5.4

0.048±0.021

0.02

 Kinship

0.2

 

0.63

Subordinate female clutch size (N=17, n=25)

 Intercept

4.3

1.974±0.956

0.039

 Female body size

2.8

0.036±0.021

0.095

 Kinship

0.02

 

0.88

Subordinate female egg mass (N=16, n=21)

 Intercept

4

0.215±0.080

0.044

 Female body size

17.4

0.0075±0.0018

<0.001

 Kinship

9.5

−0.1004±0.0325

0.002

  1. df=1 for each independent variable, ‘Female body size’ and ‘Duration’ are covariates. Duration refers to the experimental period in days (the groups were observed for 29 to 256 days; the analyses exclude one kin group that had been terminated earlier). Coefficients for non-kin; kin is the reference category.
  2. Depicted are six separate models; the interaction kinship × female body size was not significant in all cases (P>0.13). Nonsignificant effects are shown with their statistics for entry into the models, significant effects are shown with their coefficients. GLMs with log-link, the scaling parameter adjusted using the deviance method for clutches produced; GEEs with log-link, the scaling parameter adjusted using the deviance method for clutch sizes; GEEs with identity-link, the scaling parameter adjusted using the deviance method for egg masses. The GEEs contain female identifiers as subjects (in brackets: N=number of females, n=number of clutches sampled). Egg mass is average mass of a single egg for that particular female.
Back to article page