400-million years of 'fishes': a survey ofsampling biases based on the UK record

Graeme T. LloydMatt Friedman

‘fishes’ (ca. 28,000)

species counts from Nelson (2006)

Extant Vertebrate Diversity

Historical ‘Fish’ Diversity

Agassiz 1833-1843

Historical ‘Fish’ Diversity

Benton 1998 (data from Fossil Record 2)

1678 occurrences 100 localities 683 species 437 genera 70 geologic formations

The Database

Collector Curve

Genus richness

Fish-bearing geologic formations

Fish-bearing localities

Grid occupancy

1 2 3 4

0.5-degree net localities grids sampled grids occupied

Grid occupancy

Correlations

Correlation Raw (rho) G.D. (rho)Genus richness vs. Formations 0.66 0.48Genus richness vs. Localities 0.67 0.59

Genus richness vs. Grids 0.75 0.66

p > 0.05 p < 0.05

Sampling correction - rarefaction

Sampling correction - formations

Sampling correction - localities

Sampling correction - grids

Chondrichthyes Osteichthyes Clade comparison

Chondrichthyes Osteichthyes Genus richness

Chondrichthyes Osteichthyes

Raw (rho) G.D. (rho)0.87 0.65

p > 0.05 p < 0.05

Modeling - formations

Raw (rho) G.D. (rho)0.70 0.53

Chondrichthyes Osteichthyes Modeling - localities

Raw (rho) G.D. (rho)0.94 0.87

p > 0.05 p < 0.05

Raw (rho) G.D. (rho)0.69 0.37

Chondrichthyes Osteichthyes Modeling – grid occupancy

Raw (rho) G.D. (rho)0.93 0.83

p > 0.05 p < 0.05

Raw (rho) G.D. (rho)0.72 0.57

Agassiz 1833/43 –EuropeanSpecies

Benton 1993 –Globalfamilies

Carroll 1988 –Globalgenera

Sepkoski 2002 –Marinegenera

Global curves

Dataset correlations

UK Agassiz1 Benton Carroll Sepkoski2

UK 0.39 0.76 0.67 0.68Agassiz1 0.43 -0.11 -0.26 0.18Benton 0.61 -0.15 0.52 0.72Carroll 0.51 -0.20 0.78 0.38

Sepkoski2 0.65 0.26 0.90 0.71Pearson

Spe

arm

an

p > 0.05 p < 0.05 1 European taxa only2 marine taxa only

(Correlations based on generalized differences of log10 data)

Dataset correlations

UK Agassiz1 Benton Carroll Sepkoski2

UK 0.39 0.76 0.67 0.68Agassiz1 0.43 -0.11 -0.26 0.18Benton 0.61 -0.15 0.52 0.72Carroll 0.51 -0.20 0.78 0.38

Sepkoski2 0.65 0.26 0.90 0.71Pearson

Spe

arm

an

p > 0.05 p < 0.05 1 European taxa only2 marine taxa only

(Correlations based on generalized differences of log10 data)

Dataset correlations

UK Agassiz1 Benton Carroll Sepkoski2

UK 0.39 0.76 0.67 0.68Agassiz1 0.43 -0.11 -0.26 0.18Benton 0.61 -0.15 0.52 0.72Carroll 0.51 -0.20 0.78 0.38

Sepkoski2 0.65 0.26 0.90 0.71Pearson

Spe

arm

an

p > 0.05 p < 0.05 1 European taxa only2 marine taxa only

(Correlations based on generalized differences of log10 data)

Dataset correlations

UK Agassiz1 Benton Carroll Sepkoski2

UK 0.39 0.76 0.67 0.68Agassiz1 0.43 -0.11 -0.26 0.18Benton 0.61 -0.15 0.52 0.72Carroll 0.51 -0.20 0.78 0.38

Sepkoski2 0.65 0.26 0.90 0.71Pearson

Spe

arm

an

p > 0.05 p < 0.05 1 European taxa only2 marine taxa only

(Correlations based on generalized differences of log10 data)

• First sampling corrected curves of fish richness:

Le conclusions

• First sampling corrected curves of fish richness:• Devonian diversity is far lower than expected…

Le conclusions

• First sampling corrected curves of fish richness:• Devonian diversity is far lower than expected…• …yet Paleogene rise survives…

Le conclusions

• First sampling corrected curves of fish richness:• Devonian diversity is far lower than expected…• …yet Paleogene rise survives…• …Cenozoic true “age of fishes”?

Le conclusions

• First sampling corrected curves of fish richness:• Devonian diversity is far lower than expected…• …yet Paleogene rise survives…• …Cenozoic true “age of fishes”?

• Chondricthyans are more correlated with sampling than osteichthyans

Le conclusions

• First sampling corrected curves of fish richness:• Devonian diversity is far lower than expected…• …yet Paleogene rise survives…• …Cenozoic true “age of fishes”?

• Chondricthyans are more correlated with sampling than osteichthyans

• UK record accounts for one half to two-thirds of global signal

Le conclusions

• First sampling corrected curves of fish richness:• Devonian diversity is far lower than expected…• …yet Paleogene rise survives…• …Cenozoic true “age of fishes”?

• Chondricthyans are more correlated with sampling than osteichthyans

• UK record accounts for one half to two-thirds of global signal

• Estimates of global fish richness have changed substantially in last 170 years

Le conclusions