Table 1 Results of generalised least squares regression of log10 subsampled non-marine genus biodiversity (quorum=0.4) on the δ18O palaeotemperature proxy of Zachos et al.17

From: Climate constrains the evolutionary history and biodiversity of crocodylians

Environment

Region

Palaeotemp.

N

GLS

OLS (untransformed)

OLS (fd)

    

Phi

Interc.

Slope

Intercept

Slope

R 2

Interc.

Slope

R 2

Continental

North America

Zachos

9

−0.11

0.42

−0.13** (0.023)

0.41

−0.13** (0.041)

0.39

−0.03

0.03 (0.853)

−0.16

Continental

Europe

Zachos

6

−0.86

1.14

−0.50** (<0.001)

1.09

−0.47** (0.003)

0.89

0.12

−0.83** (0.038)

0.75

  1. ‘Palaeotemp.’ gives the source of δ18O data; ‘GLS’ denotes generalised least squares regression incorporating a first-order autoregressive covariance model; OLS denotes ordinary least squares regression; ‘fd’ indicates that first-differencing was applied to the input data series; phi is the serial correlation coefficient70; ‘Intercep.’ is the y-intercept; R2 is the adjusted R2 of ordinary least squares regression, and comparable R2 values cannot be computed for generalise least squares. Notes: **significant at alpha=0.05.
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