(a) Data collection
For our mitochondrial π dataset, we compiled 1781 population-level
measurements of genetic diversity, while for Hdwe compiled 1871 diversity measurements. Collectively, these
observations came from 239 studies and represented 262 species in 82
families. For microsatellites, we recorded genetic diversity
(He ) from 3210 populations, 578 studies, and 341
species in 86 families. When recorded for the same population, nuclearHe was not strongly correlated with either
mitochondrial π or Hd(He -π rs = 0.242;He -Hd rs =
0.349) although π and Hd were positively related
to each other (π-Hd rs = 0.818)
(Fig. S1). Mean chlorophyll-a concentration and mean SST were also not
strongly correlated with each other (rs = -0.316) (Fig.
S2 & S3).
These nuclear and mitochondrial datasets represented populations from
across the globe, spanning all latitudes, every ocean basin, and a wide
array of environmental conditions (Fig. 1, S4-S6). Coastlines in the
Northern hemisphere were the most densely sampled regions in our
database. However, there were also a large number of diversity estimates
near the Equator, particularly in the Coral Triangle. While the number
of datapoints decreased towards the poles for both mitochondrial and
nuclear diversity, there were still a substantial number of diversity
estimates at latitudes greater than 60 °N or S for both mitochondrial
(39 observations) and nuclear (311 observations) diversity.