13-6 Integrative Landscape Genomics In The Gulf Of California And The Baja California Peninsula: Linking Terrestrial And Marine Biodiversity Patterns With Molecular Tools And Environmental Data

Session: Earth Life Sciences across the Cordillera

Presenting Author:

Tania Valdivia-Carrillo

Authors:

Valdivia-Carrillo, Tania¹, Rocha Olivares, Axayácatl², Munguia Vega, Adrian³, Reyes Bonilla, Hector⁴, Garcia de Leon, Francisco Javier ⁵, Marinone Moschetto, Silvio Guido⁶

(1) Centro de Investigaciones Biológicas del Noroeste (CIBNOR), La Paz, Baja California Sur, Mexico, (2) Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Ensenada, BC, Mexico, (3) The University of Arizona, La Paz, BCS, Mexico, (4) Universidad Autónoma de Baja California Sur (UABCS), La Paz, BCS, Mexico, (5) Centro de Investigaciones Biológicas del Noroeste (CIBNOR), La Paz, BCS, Mexico, (6) Ensenada, BC, Mexico,

Abstract:

 

 

 

 

The Gulf of California (GC) and the Baja California Peninsula (BCP) form a marine–terrestrial interface where strong environmental gradients on land and dynamic oceanography at sea jointly influence dispersal, effective connectivity, and biodiversity structure. Understanding how abiotic drivers interact with species traits to shape biodiversity across this land–sea system remains a key challenge. Here, we synthesize an integrative landscape genomics framework that combines genome-wide population inference and fish eDNA metabarcoding with environmental and oceanographic predictors to characterize connectivity and biogeographic patterning across the region.

 

We integrate three complementary datasets spanning genes to communities: (1) landscape genomics of the desert iguana (Dipsosaurus dorsalis) across the BCP, (2) seascape genomics of the leopard grouper (Mycteroperca rosacea) in the GC, and (3) fish eDNA metabarcoding in the GC. The terrestrial analysis reveals spatial genetic structure consistent with Pleistocene climatic fluctuations and contemporary environmental gradients, supporting geography- and environment-dependent connectivity along the peninsula. In the marine realm, neutral genomic connectivity in M. rosacea is best predicted by current-mediated dispersal proxies derived from ocean circulation, consistent with multigenerational larval transport. At the community level, eDNA metabarcoding complements traditional surveys by recovering broad-scale biogeographic structure and discrete community transitions, with turnover patterns consistent with the joint action of dispersal limitation and environmental filtering.

 

This synthesis shows that coupling genome-wide population inference with eDNA metabarcoding within a common set of environmental and oceanographic spatial predictors enables robust characterization of biodiversity structure in the GC–BCP system. Population genomic data resolve effective connectivity and barriers to gene flow at the species level, while eDNA metabarcoding captures community-level composition turnover and identifies biogeographic transitions that may be missed by traditional surveys. Integrating both molecular signals within a common spatial framework allows direct comparison of dispersal limitation versus environmental filtering across biological scales, highlights convergent breaks identified by independent data types, and delineates transition zones that can be prioritized for targeted sampling and hypothesis testing.

Geological Society of America Abstracts with Programs. Vol. 58, No. 3, 2026

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