Biology subjects

Lopez-Idiaquez, D.

Publications and source records attributed to Lopez-Idiaquez, D..

8 recordsLinked to original sources

bioRxiv2026

Broad scale environmental conditions, not urbanisation, explain geographic variation in great tit feather microstructure

Urbanisation imposes novel environmental conditions that can shape phenotypic traits including plumage, yet, its effects on characteristics beyond colouration remain poorly understood. Feather microstructure plays an important role in thermoregulation, protection from solar radiation and waterproofing, and its expression is sensitive to environmental conditions. Here, we quantified feather barbule density, a key component of feather microstructure, in great tits (Parus major) from five urban-rural paired populations across Europe to assess its association with urbanisation, temperature and elevation. We found no significant effects of the urban environment or temperature. However, feather microstructure significantly varied between the studied areas and was positively associated with elevation and ultraviolet B (UV-B) radiation, suggesting a potential adaptive response to variation in solar radiation.

ecology↗

bioRxiv2026

Strength of developmental carry-over varies continuously with environmental conditions in a wild bird population

Early-life phenotypes frequently predict adult phenotypes through developmental 'silver-spoon' carry-over effects, but how strongly and under what circumstances? Using 40 years of individual-based data from a great tit (Parus major) population, we used covariance reaction norms to understand how the natal-to-adult body mass association shifts across temperature, rainfall, and population density gradients during both life stages. We show that the natal-adult mass correlation is substantial (r {approx} 0.7) but strongly environment-dependent. Reaction norm shapes across climatic and density axes point to distinct mechanisms, including compensatory growth under benign adult conditions and density-dependent modulation of early-life differences. We further show that the conditions experienced in adulthood largely drive these patterns and determine whether early-life advantages are retained, even when explicitly tested within an environmental-matching paradigm. Decomposing the correlation using 38 generations of pedigree data revealed no evidence of gene-by-environment interactions. Instead, the observed phenotypic correlation reaction norms could be attributed almost entirely to environmentally-sensitive non-genetic individual differences. Overall, our findings show that climatic and demographic shifts can substantially reshape developmental carry-over without altering the genetic architecture tying body mass across life stages, with implications for how reliably early-life mass can predict individual quality and adult traits in wild animal populations.

ecology↗

bioRxiv2026

Not-so-great tits: early-life environment drives long-term decrease in adult body mass in a wild bird population

Body mass is a key organismal characteristic that impacts many physiological and ecological processes and often a strong determinant of fitness. Recent studies have documented temporal phenotypic changes in this trait in many populations, but identifying the mechanisms underpinning these changes can be difficult. Here, we use 47 years of data to analyse how adult and nestling body mass have changed over time in a great tit Parus major population in Wytham Woods (UK). Further, we link those changes to three environmental variables previously recognised as drivers of body mass: temperature, intra- and inter-specific competition and temporal mismatch with a key prey during breeding, winter moth Operophtera brumata caterpillars. Temporal analyses of adult body mass revealed contrasting dynamics at the between- and within-cohort levels, mirroring Simpsons Paradox. At the population level we report a marked decrease in body mass in adults between 1978 and 2024 (-0.042 Haldanes), and show that this results from phenotypic plasticity, driven by a negative between-cohort trend likely reflecting carry-over effects of the early environment. Within cohorts, however, trends were consistently positive likely reflecting an age-dependent mass increase. The change in adults was paralleled by a change in nestling body mass (-0.036 Haldanes). Nestling mass was negatively associated with estimated intensity of intraspecific competition, as well as inter-specific competition from blue tits Cyanistes caeruleus, as quantified by local population density. These effects carried over to adulthood, as shown by a negative association between adult mass and the population density experienced at early life. Temperature during development and mismatch with the caterpillar food supply, despite being associated with adult and nestling mass, did not explain the observed declines in mass, largely because these have not changed over time. Overall, our results illustrate the potential for effects mediated early in development to carry-over into long-term phenotypic change at later life history stages, and emphasise the value of considering multiple effects as drivers of phenotypic change in natural populations.

evolutionary biology↗

bioRxiv2025

Independent colonisations of serpentine habitats highlight species-specific evolutionary histories of lineage diversification

Serpentine soils are characterized by high levels of heavy metals, low nutrient availability, and water scarcity, presenting significant ecological challenges for plant species. Nonetheless, some species have adapted successfully to these conditions. We investigate the population genomic structure, evolutionary history and phenotypic differentiation of three diploid generalist plant species, Lavandula stoechas L., Halimium atriplicifolium (Lam) Spach. subsp. atriplicifolium, and Phlomis purpurea L., all of which inhabit adjacent serpentine and non-serpentine soils in the Malaga region in the southern Iberian Peninsula (Spain). We explore whether populations from serpentine and non-serpentine soils represent distinct evolutionary lineages and whether there is genomic and phenotypic differentiation associated with serpentine conditions. We measured plant height and specific leaf area (SLA) to detect potential ecotypic variation associated with soil type. A ddRADseq SNP dataset was generated for each species, representing 10 populations from serpentine and 10 from non-serpentine soils. We ordinated genotype data to assess genomic variation, conducted an ADMIXTURE analysis to infer ancestral groups, and used Treemix analyses to investigate phylogenetic relationships and gene flow events between populations. Isolation by distance (IBD) analyses evaluated the role of geographic separation in observed genomic differentiation. Our results reveal species-specific patterns of genomic, and to some extent phenotypic, differentiation between serpentine and non-serpentine populations, with evidence of multiple colonisations of serpentine sites in all three species. The study highlights the role of historical differentiation and subsequent gene flow in shaping the genomic structure of plant populations, alongside observed variation in phenotypic traits across environments.

evolutionary biology↗

bioRxiv2025

Developmental stage-specific responses to extreme climatic events and environmental variability in great tit nestlings

Climate change poses a pervasive threat to many aspects of natural systems, and while impacts of changes in average conditions have been extensively studied, the effects of increased climate variability, and extreme events, on natural populations are less understood due to the challenges of studying these rare occurrences. Using 60 years of life-history data from over 83,000 individuals, and historical daily climate records, we show that developmental stages in wild great tits (Parus major) differ in their sensitivity to extreme climatic events (ECEs). Exposure to extreme cold events during the first week of development is particularly detrimental to fledging mass, while extreme rain events have a stronger negative impact as chicks grow older and their energetic requirements increase. Synergistic effects of ECEs and average climatic conditions can be particularly severe, exacerbating the challenges faced by these birds. Our findings indicate that combined exposure to extreme heat and heavy rainfall during early development is associated with a predicted reduction in fledging mass by up to 27%. Additionally, birth timing may further modulate these effects, since late-season broods exposed to frequent hot ECEs during early development are predicted to fledge nestlings up to 4.27 standard deviations (35%) lighter than broods laid earlier in the season. Moreover, phenotypic plasticity has enabled many similar populations to shift towards an overall earlier laying date, which may have increased susceptibility to cold extremes during development. However, our analyses suggest that the benefits of being part of an early-laid clutch within a season may, to some extent, offset the negative effects of extreme climate on fledging mass and apparent survival. In climate scenarios where ECEs are predicted to increase in frequency, duration, and severity, these developmental stage-specific insights are crucial for understanding how climate change may be influencing wild avian populations.

ecology↗

bioRxiv2025

Disentangling urbanisation, climate effects and their interaction on ornamental colourations

Urbanisation and climate change can both affect phenotype expression across taxa. Most evidence collected so far has focused on exploring these two phenomena on isolation. Currently, the combined effects of climate change and urbanisation remain underexplored, despite being among the greatest challenges faced by biodiversity. Here, we use a decade-long, individual-based study of urban and forest great tits (Parus major) to analyse urbanisation, climate and their interactive effects on yellow breast colouration, a carotenoid-based trait. We find that urban birds exhibit duller colourations than forest counterparts, being 10-20% less chromatic, with first-year birds and males being more negatively impacted by cities. Additionally, birds in the city are more sexually dichromatic than in the forest. Over the decade, colouration differences between habitats remain stable, following a similar quadratic temporal pattern. Finally, while climate has a weak effect on colouration, urban birds appear more sensitive to its influence than forest birds. Our results indicate urbanisation has a stronger impact than last decade climatic variation on great tit colouration, though both factors may interact. The heightened sensitivity of first-year birds and increased sexual dichromatism in cities may alter the strength of natural and sexual selection on this trait in urban environments.

ecology↗

bioRxiv2024

Optimal thermal niche-tracking buffers wild great tits against climate change

Animal and plant populations are responding to climate change by shifting the timing of key seasonal events. However, while measuring responses of natural systems on human calendars provides a standard scale of measurement it reveals little about the underlying biological causes and mechanisms of change. Here, using data from a six decade longitudinal, individual-based, study of great tits Parus major, we show that changing the timing of breeding has enabled birds to track specific temperatures at different stages in reproduction. We show, further, that multiple measures of reproductive success are maximised at intermediate, stage-specific, temperatures that correspond to the temperatures tracked while climate has changed in recent decades. Finally, we show that tracking temperatures has allowed great tits to match reproduction with a key food source for nestling development, the winter moth Operophtera brumata. Consequently, phenotypic plasticity in reproductive timing has enabled great tits to track temporal changes in the environmental conditions that maximise individual reproductive success. Shifting our perspective from analysing the phenological timing of life history events under climate change to analysing changes relative to environmental gradients has the potential to shed new light on the causes, mechanisms, and consequences of these shifts.

evolutionary biology↗

bioRxiv2022

Urbanisation impacts plumage colouration in a songbird across Europe: evidence from a correlational, experimental, and meta-analytical approach

Urbanisation is increasing at a phenomenal rate across the globe, transforming landscapes, presenting organisms with novel challenges, shaping phenotypic traits, and even impacting fitness. Among colour traits, urban individuals are widely claimed to have duller tones in carotenoid-based traits, the so-called "urban dullness" phenomenon. However, at the intra-specific level, this generalisation is surprisingly inconsistent and often based on examples from single urban/non-urban population pairs or a limited geographic area. Here, combining correlational, experimental, and meta-analytical results from a common songbird, the great tit (Parus major), we investigated carotenoid-based plumage coloration in urban and forest populations across Europe. We find that, as predicted, urban individuals are paler than forest individuals. Interestingly, we also find large population-specific differences in the magnitude of the urban-forest contrast in plumage colouration. Moreover, our meta-analysis indicates a non-significant effect of environmental pollution on carotenoid-based plumage for the species, suggesting that the observed differences across urban populations are not only driven by pollution. Finally, using one region as an example (Malmo, Sweden), we reveal population-specific processes behind plumage colouration differences, which are likely the result of variation in the spatial and temporal distribution of carotenoid-rich resources in anthropogenic environments. This is the first study to quantify the consistency of an oft-cited textbook example of the impact of urbanisation on wildlife; our results provide the most convincing evidence to date of the "urban dullness" phenomenon, but also highlight that the magnitude of the phenomenon depends on local urban characteristics.

evolutionary biology↗