Table 3. Ability of the occupied niche to describe properties of the physiological niche, comparing across three niche property estimators (centroid, area, MCP), both fundamental and existing niches, and three fitness thresholds (TNZ, LD50, LD100).

Thermal niche type & fitness thresholda	Centroid distance				Area overlapf			MCPg overlap
	Min tempb	Max tempc	Distanced	Percentile scoree	Intersect	Union	Ratio scoreh	Intersect	Union	Ratio scoreh
Occupied niche	−7.12	28.91	0.00	NA	4.8	4.8	100.00	815.9	815.9	100.00
Fundamental-TNZ	26.73	31.87	33.98	2.0	0.0	125.7	0.00	0.0	936.1	0.00
Fundamental-LD50	−1.40	20.30	10.34	26.7	4.6	2128.9	0.21	761.1	2180.3	34.91
Fundamental-LD100	−7.50	20.00	8.92	32.8	4.8	3415.2	0.14	815.9	3403.1	23.98
Existing-TNZ	22.06	31.38	29.29	3.1	0.0	5.0	0.00	0.0	817.5	0.00
Existing-LD50	−6.74	26.45	2.49	85.9	4.6	65.4	7.01	760.9	1094.2	69.53
Existing-LD100	−16.39	21.49	11.88	21.5	4.8	112.6	4.23	815.9	1392.2	58.61

^aTNZ  =  thermal-neutral zone, LD50 = 50% population mortality, LD100 = 100% population mortality.

^bMinimum temperature of the coldest month (°C).

^cMaximum temperature of the warmest month (°C).

^dEuclidian distance in climate space from the occupied niche centroid to the thermal niche centroid.

^ePercentile of occupied centroid distance within distribution of distances from all occupied grid cells to the thermal niche centroid. To ease interpretation in relation to area metrics, percentiles are subtracted from 100%, thus a high percentile score represents a close match between centroids relative to the distribution of all occupied grid cells.

^fArea is calculated as the sum of individual 0.1×0.1°C thermal niche grid cells. Areas of occupied cells are compared to areas of the thermal niche. High ratios of overlap indicate higher occurrence within the available environmental space.

^gMinimum convex polygon.

^hThe ratio score is calculated as the area of intersect divided by the area of union, expressed as a percentage.