PT  - JOURNAL ARTICLE
AU  - J. Igea
AU  - A. J. Tanentzap
TI  - Angiosperm speciation speeds up near the poles
AID  - 10.1101/619064
DP  - 2020 Jan 01
TA  - bioRxiv
PG  - 619064
4099  - http://biorxiv.org/content/early/2020/01/14/619064.short
4100  - http://biorxiv.org/content/early/2020/01/14/619064.full
AB  - Recent evidence has questioned whether the Latitudinal Diversity Gradient (LDG), whereby species richness increases towards the Equator, results from higher rates of speciation in the tropics. Allowing for time heterogeneity in speciation rate estimates for over 60,000 angiosperm species, we found that the LDG does not arise from variation in speciation rates because lineages do not speciate faster in the tropics. These results were consistently retrieved using two other methods to test the association between occupancy of tropical habitats and speciation rates. Our speciation rate estimates were robust to the effects of both undescribed species and missing taxa. Overall, our results show that speciation rates follow an opposite pattern to global variation in species richness. Greater ecological opportunity in the temperate zones, stemming from less saturated communities, higher species turnover or greater environmental change, may ultimately explain these results.