Data from: Miocene to present turnover of mollusk assemblages: insights into coastal-marine ecosystem evolution along the Peruvian Margin
Data files
Jul 27, 2026 version files 66.80 KB
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Medina-Franco_etal_SupplementaryTable2_References.csv
34.39 KB
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Medina-Franco_etal_SupplementaryTable2.csv
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README.md
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Abstract
Over the past 10 million years, the Peruvian Margin has undergone significant tectonic and oceanographic changes, including the intensification of the Humboldt Current System and the uplift of the Andes. While the evolutionary history of vertebrates during this period is well documented, invertebrate history remains to be understood. This dataset provides chronostratigraphically controlled molluscan records necessary to evaluate long-term diversification patterns, containing 184 genera and 84 families of fossil and modern mollusks (Bivalvia and Gastropoda) from the East Pisco Basin (13–16 ºS) compiled from published literature and primary museum collections. The dataset includes First Appearance Datum (FAD) and Last Appearance Datum (LAD) records for 83 gastropod and 101 bivalve genera linked to modern and chronostratigraphically controlled units (Pisco, Caracoles, and Pongo Formations), along with ecological trait assignments for bivalve life habit, mobility, shell fixation, and diet and gastropod life habit and diet. These primary records were subsequently classified into 12 discrete one-million-year time bins (12–0 Ma) and subjected to range-through analysis to create the presence-absence matrix used in the associated study.
Dataset DOI: 10.5061/dryad.g4f4qrg46
Description of the data and file structure
Data Sources and Compilation. The molluscan occurrence dataset was compiled from three primary sources: (1) published paleontological and geological reports covering the East Pisco Basin , (2) digitized records from international and local paleontological databases, including the Paleobiology Database and the Paleontological Research Institution (PRI), and (3) physical malacological collections housed at the Universidad Nacional Mayor de San Marcos (MUSM), the Universidad Peruana Cayetano Heredia (UPCH), and the Burke Museum (UWBM). Modern reference data were gathered from published literature and existing collections of the Peruvian littoral to provide a baseline for extant community composition.
Taxonomic Curation. The taxonomic identity and status of each fossil and modern entry were reviewed and updated to reflect current nomenclature and chronostratigraphy. All analyses were performed at both the genus and species levels to account for varying degrees of taxonomic resolution. Certain groups with poor preservation or limited morphological distinction, such as the family Ostreidae, were excluded to ensure data quality.
Chronostratigraphic Control and Binning. Occurrence records were assigned to specific geological units within the East Pisco Basin, including the Pisco (10–4.5 Ma), Caracoles (2.7–1.9 Ma), and Pongo (~1.9–1.4 Ma) Formations, as well as Huacllaco sediments (3.4–1.4 Ma) and Late Pleistocene marine terraces (<1 Ma). These occurrences were then classified into 12 discrete one-million-year time bins, following a range-through approach, spanning from 12 Ma to the present.
Ecological Trait Assignment. Ecological traits were assigned to each taxon based on established molluscan life-habit databases. Bivalves were categorized by life habit (e.g., infaunal, epifaunal), mobility (active, immobile, sedentary), shell fixation (cemented, byssally attached, unattached), and diet. Gastropods were categorized by life habit and diet (carnivores, grazers, suspension feeders). When specific data were unavailable, traits were inferred based on phylogenetically conserved characteristics of the genus or family. The Todd Molluscan Life Habits Database (https://nmita.rsmas.miami.edu/database/mollusk/mollusclifestyles.htm) was a primary source for ecological trait assignments.
Files and variables
File 1: Medina-Franco_etal_SupplementaryTable2.csv
Description: Compiled database of mollusk genera in the last 12 Ma. It includes taxonomic information, First Appearance Datum (FAD), Last Appearance Datum (LAD), Life Habit (e.g. infaunal, epifaunal), Mobility (e.g., actively mobile, immobile), Shell Fixation (e.g., unattached, bysally attached), Diet (e.g., suspension feeder, grazer), and Status (i.e., extinct, extant, locally extinct). Empty data cells are filled with "null" to indicate traits that do not apply to each taxonomic group (e.g., Mobility and Shell Fixation are not assigned to gastropods, which lack these bivalve-specific characteristics).
Variables
- Taxonomic: Phyllum, Class, Family, Genus, Authority
- Ecological traits: Life Habit, Mobility, Shell Fixation, Diet, Ecology Reference
- Status: Extant, Extinct, LE (i.e., locally extinct)
- Temporal: First Appearance Datum (FAD), Last Appearance Datum (LAD)
File 2: Medina-Franco_etal_SupplementaryTable2_References.csv
Description: Complete list of references cited in the Ecology Reference field of the main dataset. Empty cells in the "Todd Ref #" column are filled with "null" to indicate references that do not originate from the Todd Molluscan Life Habits Database.
Code/software
The data are in .csv format. Any spreadsheet software or text editor can be used to access the database.