Table 2.
Summary of simulation parameters
| Parameter | Description | Parameter space |
|---|---|---|
| Initial abundance | When a new cell is colonised, it is seeded with an initial abundance (whereafter the abundance returns to 1 with each time step). | 0.11–1. From the minimum value before extinction to full abundance on colonisation. |
| Thermal optimum | The thermal optimum of the root species at the start of the simulation was varied across the entire temperature range present in all habitable cells across the entire simulation. | 17–31.4 °C. Values from [77]. |
| Dispersal distance | The distance a species can disperse from cell-to-cell at each time step. This determines inter-population connectivity and colonisation events. These values are taken from a Weibull distribution approximating the probability distribution of dispersal events. | The scale of the Weibull dispersal kernel was varied from 100 to 5000 km based on long-term movement observations reported by [81] for non-pelagic coral reef fishes. The shape was set to 2.5. |
| Speciation threshold | The divergence threshold at which two populations will speciate. | 12–600 timesteps, equivalent to between 20 ka and 1 ma. The divergence required for two populations to allopatrically speciate is complex [49]. Here, we simply explore as wide a range of values as possible. |
| Mutation rate | The standard deviation of the normal distribution around the thermal and competitive nice traits from which new trait values are picked at each time step. | 0.01 to 0.15. These values were based on estimation based on preliminary simulations. |
| Competitive niche width | The amount of competitive space around the competitive niche trait value within which other species will compete. | 0.02 to 0.50. The competitive niche width was varied from 0.02 to 0.50 based on preliminary simulations. |