Table 2 Results of generalized linear mixed-model analyses to test the effect of cichlid ecomorphs on carbon and nitrogen stable isotope ratios of their muscles

  Ecomorph

Estimate

SE

DF

t value

p

   Intercept (biter)

−15.75

2.69

13.0

−5.86

<0.001

   browser

 2.51

2.87

13.0

 0.88

NS

   grazer

 2.76

2.87

13.0

 0.96

NS

   plankton eater

 −5.29

3.29

13.0

−1.61

NS

   scooper

 0.42

3.80

13.0

 0.11

NS

   scraper

 7.02

3.80

13.0

 1.85

NS

  Post-hoc test

Estimate

SE

z value

p

   browser-biter

 2.51

2.87

 0.88

NS

   grazer-biter

 2.76

2.87

 0.96

NS

   plankton eater-biter

 −5.29

3.29

−1.61

NS

   scooper-biter

 0.42

3.80

 0.11

NS

   scraper-biter

 7.02

3.80

 1.85

NS

   grazer-browser

 0.25

1.44

 0.17

NS

   plankton eater-browser

 −7.80

2.15

−3.62

<0.01

   scooper-browser

 −2.10

2.87

−0.73

NS

   scraper-browser

 4.50

2.87

 1.57

NS

   plankton eater-grazer

 −8.05

2.15

−3.74

<0.01

   scooper-grazer

 −2.34

2.87

−0.82

NS

   scraper-grazer

 4.26

2.87

 1.48

NS

   scooper-plankton eater

 5.70

3.29

 1.73

NS

   scraper-plankton eater

 12.30

3.29

 3.74

<0.01

   scraper-scooper

 6.60

3.80

 1.74

NS

δ ¹⁵ N

  Ecomorph

Estimate

SE

DF

t value

p

   Intercept (biter)

 3.87

0.81

13.0

 4.77

<0.001

   browser

 1.64

0.87

13.0

 1.89

NS

   grazer

 0.30

0.87

13.0

 0.34

NS

   plankton eater

 2.13

0.99

13.0

 2.14

NS

   scooper

 2.29

1.15

13.0

 2.00

NS

   scraper

 0.60

1.15

13.0

 0.52

NS

  Post-hoc test

Estimate

SE

z value

p

   browser-biter

 1.64

0.87

 1.89

NS

   grazer-biter

 0.30

0.87

 0.34

NS

   plankton eater-biter

 2.13

0.99

 2.14

NS

   scooper-biter

 2.29

1.15

 2.00

NS

   scraper-biter

 0.60

1.15

 0.52

NS

   grazer-browser

 −1.34

0.43

−3.10

<0.05

   plankton eater-browser

 0.49

0.65

 0.75

NS

   scooper-browser

 0.65

0.87

 0.75

NS

   scraper-browser

 −1.04

0.87

−1.20

NS

   plankton eater-grazer

 1.83

0.65

 2.82

<0.05

   scooper-grazer

 1.99

0.87

 2.30

NS

   scraper-grazer

 0.30

0.87

 0.35

NS

   scooper-plankton eater

 0.16

0.99

 0.16

NS

   scraper-plankton eater

 −1.53

0.99

−1.54

NS

   scraper-scooper

 −1.69

1.15

−1.47

NS