Trait-fitness associations via fecundity and competition in a two-million-year-long fossil record

The evolution of phenotypic traits is usually studied on generational times or across species on million-year timescales. We bridge this conceptual gap by using high density sampling of a species lineage, Microporella agonistes (Bryozoa, Cheilostomatida), over 2 million years of its evolutionary history, to ask if trait-fitness associations are consistent with evolutionary trait models often applied to phenotypic time series. We use average fecundity and competitive outcome as two different fitness components, where competitive outcome is a proxy for partial survival. Examining three quantitative traits in multivariate analyses, we present evidence that some traits experienced substantial selective pressures, in part controlled by past environments. A complex interplay of resource competition with an altering set of competitors and past temperatures, has contributed to the changing patterns of phenotypes within the focal species. A comparison with congeneric species living in the same r..., Fossil and contemporary bryozoan colonies were collected over several fossil field expeditions to the Whanganui Basin of North Island New Zealand and dredges in Cook Strait and Taranaki Bight. The bryozoans were encrusting on hard substrates, mainly bivalve shells. Images of bryozoans were taken with Scanning Electron Microscopy and data of colonies and images extracted using a combination of deep-learning (DEEPBRYO) and manual measurements/collection.
All the scanning electron microscope images associated with the work are supplied here and image names are associated with detailed metadata.
 , , # Data from: Trait-fitness associations via fecundity and competition in a two-million-year-long fossil record

[https://doi.org/10.5061/dryad.3ffbg79rj](https://doi.org/10.5061/dryad.3ffbg79rj)

This dataset and associated R script and images are associated with the peer-reviewed publication \"Trait-fitness associations via fecundity and competition in a two-million-year-long fossil record\" at The American Naturalist.

## Description of the data and file structure

All the bryozoan data, including the metadata data associated with the image files, are supplied in the excel file Microporella_SELECT_final_datasets_30.06.2023.xlsx. The sheets and column names are described below.

The paleo delta O18 values used are from Lisiecki and Raymo 2005, and supplied in O18.txt. The column names are described below.

The recent O18 values span 1988-2016 for the southern hemisphere latitude encompassing New Zealand (25-90°S) from NASA data repository ([https://data.giss.nasa.gov/) and are supplied i...