Species richness and speciation rates for all terrestrial animals emerge from a synthesis of ecological theories
Data files
Mar 07, 2025 version files 60.51 KB
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data_dictionary.xlsx
11.84 KB
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ectotherm_richness_estimation.csv
15.15 KB
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endotherm_speciation_rates.csv
17.34 KB
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madingley_abundances_15simulations.csv
12.03 KB
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madingley_functional_groups_min_mass.csv
468 B
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README.md
2.76 KB
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terrestrial_reptiles_distribution.csv
919 B
Abstract
The total number of species on earth and the rate at which new species are created are fundamental questions for ecology, evolution and conservation. These questions have typically been approached separately, despite their obvious interconnection. In this study we approach both questions in conjunction, for all terrestrial animals. To do this, we combine two previously unconnected bodies of theory: general ecosystem models and individual based ecological neutral theory. General ecosystem models provide us with estimated numbers of individual organisms, separated by functional group and body size. Neutral theory, applied within a guild of functionally similar individuals, connects species richness, speciation rate and number of individual organisms. In combination, for terrestrial endotherms where species numbers are known, they provide us with estimates for speciation rates as a function of body size and diet class. Extrapolating the same rates to guilds of ectotherms enables us to estimate the species richness of those groups, including species yet to be described. We find that speciation rates per species per million years decrease with increasing body size. Rates are also higher for carnivores compared to omnivores or herbivores of the same body size. Our estimate for the total number of terrestrial species of animals is in the range 1.03-2.92 million species, a value consistent with estimates from previous studies, despite having used a fundamentally new approach. Perhaps what is most remarkable about these results is that they have been obtained using only limited data from larger endotherms and their speciation rates, with the predictive process being based on mechanistic theory. This work illustrates the potential of a new approach to classic eco-evolutionary questions, while also adding weight to existing predictions. As we now face an era of dramatic biological change, new methods will be needed to mechanistically model global biodiversity at the species and individual organism level. This will be a huge challenge but the combination of general ecosystem models and neutral theory that we introduce here is a way to tractably achieve it.
https://doi.org/10.5061/dryad.h44j0zpvc
The data was produced by first conducting simulation runs of the Madingley Model using default parameters
Harfoot, M.B., Newbold, T., Tittensor, D.P., Emmott, S., Hutton, J., Lyutsarev, V., Smith, M.J., Scharlemann, J.P. and Purves, D.W., 2014. Emergent global patterns of ecosystem structure and function from a mechanistic general ecosystem model. PLoS biology, 12(4), p.e1001841.
We also used empirical data from
Wilman, H., Belmaker, J., Simpson, J., de la Rosa, C., Rivadeneira, M.M. and Jetz, W., 2014. EltonTraits 1.0: Species‐level foraging attributes of the world's birds and mammals: Ecological Archives E095‐178. Ecology, 95(7), pp.2027-2027.
and
Etard, A., Morrill, S. and Newbold, T., 2020. Global gaps in trait data for terrestrial vertebrates. Global Ecology and Biogeography, 29(12), pp.2143-2158.
Combined with a range of processing steps, including calculations using ecological neutral theory.
The final outputs are i) estimates of speciation rates for terrestrial endotherms, and ii) estimates of total species richness (including undescribed species) for terrestrial ectotherms. The final outputs, as well as the data from some intermediate stages are included in this dataset.
Also included is a PDF which is supplementary material to the associated manuscript.
Description of the data and file structure
- Data_dictionary file: please use to see description of all fields that appear in all other tables. This includes units for all the fields. Mass is in grams, timescales are in millions of years (see the file for full details).
- madingley_fg_min_mass file: please use to see minimum body mass of different functional groups in the Madingley model. This is required to interpret the ranges for each body mass bin as described in the main text of the paper.
- madingley_abundances_15simulations file: outputs of the madingley simulations. This is an intermediate data product
- terrestrial_reptiles_distribution file: This is an intermediate data product arising from processing input empirical data
- endotherm_speciation_rates file: main output of our analyses giving our estimates for speciation rates of terrestrial endotherms
- endotherm_speciation_rates file: main output of our analyses giving our estimates for total richness of terrestrial ectotherms (including undescribed species)
- Supplementary material file: a self contained PDF file for online supplementary information. It should be interpreted in the context of the accompanying main text which is available as a preprint.