Czech Science Foundation, No. 26-22858S (2026-2028)
Research partners: Oldřich Tomášek – Institute of Vertebrate Biology, Czech Academy of Sciences; Tomáš Albrecht – Faculty of Science, Charles University
This project, funded by the Czech Science Foundation (GAČR), investigates the ecological and evolutionary significance of circulating metabolic energy substrates in birds, with a particular focus on blood glucose and free fatty acids (FFAs). These metabolites represent the primary fuels supporting physiological performance, stress responses, and survival, yet their role in shaping individual fitness and life-history evolution in wild vertebrates remains poorly understood.
The project combines long-term individual-based data from a well-studied population of barn swallows (Hirundo rustica) with comparative analyses across temperate and tropical passerine species. This integrative approach allows the assessment of variation in blood glucose and FFAs at multiple biological levels—within individuals, among individuals, and across species—and enables testing of their links to key fitness components such as survival, fecundity, reproductive investment, and stress resilience.
A central objective is to identify the sources and regulatory mechanisms underlying variation in circulating energy substrates and to quantify their fitness consequences under natural conditions. The project further explores how blood glucose and FFAs co-evolve with life-history traits across species, contributing to broader debates on pace-of-life syndromes, metabolic strategies, and evolutionary trade-offs. Particular attention is paid to the physiological costs associated with elevated glucose levels, including oxidative stress, glycation processes, and hormonal regulation, and to the mechanisms by which birds mitigate these costs over evolutionary timescales.
The project employs a strongly interdisciplinary framework, integrating field ecology, physiological measurements, hormonal analyses, and advanced mass spectrometry–based metabolomics and lipidomics. The Biology Centre CAS contributes state-of-the-art analytical expertise for the quantification of free and lipid-bound fatty acids, metabolic biomarkers, and stress-related compounds, enabling high-resolution characterization of metabolic phenotypes in wild birds.
By linking metabolic physiology with individual fitness and macroevolutionary patterns, the project aims to establish a conceptual and empirical framework for understanding the evolutionary role of circulating energy substrates. The results are expected to advance ecological physiology, life-history theory, and evolutionary biology, while also offering broader insights relevant to metabolic health, stress biology, and comparative vertebrate physiology.
