Status and shortfalls in the availability of genetic sequences and associated metadata for Mexican mammals

Abstract

Genetic information represents an important dimension of biodiversity beyond species or ecosystems, and genetic sequences are essential for all themes in biodiversity research. Genetic data are not exempt from gaps and biases, particularly in the tropics. Even for well-studied groups like mammals, many species remain understudied, and the completeness of underlying metadata for existing sequences is largely unknown. We quantified genetic data availability for 548 species of Mexican land mammals in the NCBI Nucleotide database. We evaluated the status and completeness of metadata regarding dates, locations, and voucher information associated with sequences, noting endemic species. We located genetic data for 90% of species, including sequences for 77% of Mexican endemics. Availability was skewed, with most species having very few sequences. In our sample, 316 of 496 species (64%) had at least one record with location, date, and voucher information, yet metadata quality was highly variable, and most records lacked key spatiotemporal details. We identified highly biased coverage in nucleotide sequence availability and relatively poor metadata quality for Mexican land mammals. Despite decades of sampling, decreasing costs, and advances in museomics and sequencing, major gaps and disparities remain. At a time of open science and open data, we insist on a research culture where sampling, sequencing, and adequate metadata recording happen concurrently.