Table 2 Nitrogen Isotope Results of Coral Skeleton-bound Organic Matrix δ15N.

From: Detecting Photosymbiosis in Fossil Scleractinian Corals

Samples

Age

Photosymbiotic Assignment

Mean δ15N Muscatine Method (‰)

Mean δ15N persulfate-denitrifier method (‰)

Diploria labyrinthoformis-TR1

Modern

Z

4.07 ± 0.15

Diploria labyrinthoformis-TR2

Modern

Z

3.92 ± 0.10

Favia fragum-TR1

Modern

Z

4.55 ± 0.09

Favia fragum-TR2

Modern

Z

3.91 ± 0.21

Desmophyllum dianthus

Modern

AZ

9.49

10.30

Diploria strigosa-TR1

Holocene

Z-like

5.75 ± 0.20

Diploria strigosa-TR2

Holocene

Z-like

6.10 ± 0.10

4.42

Oulophyllia sp.

Late Miocene

Z-like

6.19

Acropora papillare

Early Miocene

Z-like

3.86

3.06

Caryophyllia sp. (1)

Early Miocene

AZ-like

11.30

Caryophyllia sp. (2)

Early Miocene

AZ-like

10.70

Antiguastrea lucasiana-TR1

Oligocene

Z-like

3.99 ± 0.34

Antiguastrea lucasiana-TR2

Oligocene

Z-like

4.14 ± 0.20

Gablonzeria sp.-TR1

Norian

Z-like

2.83 ± 0.19

3.02

Gablonzeria sp.-TR2

Norian

Z-like

4.05 ± 0.23

Disticomeandra sp. (1)-TR1

Norian

Z-like

4.65 ± 0.60

Disticomeandra sp. (1)-TR2

Norian

Z-like

4.03 ± 0.27

4.16

Disticomeandra sp. (2)-TR1

Norian

Z-like

2.64 ± 0.84

Disticomeandra sp. (2)-TR2

Norian

Z-like

3.55 ± 1.43

  1. *Error is one standard deviation from the mean. Precision of the persulfate/denitrifier method results is 0.2‰. Samples of the same species analyzed separately are labeled “(1)” and “(2).” Replicates of the same sample are labeled “TR1” and “TR2” respectively; Desmophyllum dianthus and the Miocene samples did not yield enough mass for replicates. Zooxanthellate- (Z) and Azooxanthellate-like (AZ) morphologies are inferred based on morphological characters11. Z = zooxanthellate coral (modern), AZ = azooxanthellate coral (modern), Z-like = zooxanthellate-like coral (fossil), AZ-like = azooxanthellate-like coral (fossil).