Data from: Cenozoic dynamics of shallow-marine biodiversity in the Western Pacific

Aim: Cenozoic dynamics of large-scale species diversity patterns remain
poorly understood, especially for the Western Pacific, in part, because of
the paucity of well-dated fossil records from the tropics. This article
aims to reveal the spatiotemporal dynamics of species diversity in the
Western Pacific through the Cenozoic, focusing on the tropical
Indo-Australian Archipelago (IAA) biodiversity hotspot. Location: Tropical
and north-western Pacific Ocean. Methods: We analysed well-preserved
fossil ostracodes from the tropical Western Pacific and combined their
diversity data with other published data from the region to reconstruct
Cenozoic dynamics of species diversity in the tropical and north-western
Pacific Ocean. We fitted generalized additive models to test for
differences in richness over time and across geographical regions while
accounting for sample-size variation among samples. Results: Low-, mid-
and high-latitude regions all show a similar diversity trajectory:
diversity is low in the Eocene and Oligocene, increases from the Early
Miocene to the Plio-Pleistocene but then declines to the present day.
Present-day high biodiversity in these regions was established during the
Pliocene with a remarkable diversity increase at that time. Latitudinal
diversity patterns are relatively flat and never show a simple decline
from the tropics to higher latitudes. Main conclusions: Western Pacific
Cenozoic ostracodes exhibit a spatiotemporal pattern of species diversity
that is inconsistent with the commonly reported and persistent pattern of
declining diversity from the tropics to the extratropics. While this
inconsistency could be interpreted as evidence that ostracodes are a
contrarian clade, Atlantic ostracodes display a standard latitudinal
species diversity gradient. Contrasting patterns between oceans suggest an
important role for regional factors (e.g. plate tectonics and temporal
geomorphological dynamics) in shaping the biodiversity of the Western
Pacific.