Cristiana I. Marques

BIOPOLIS-CIBIO Research Center in Biodiversity and Genetic Resources · EVOLGEN

Nests are essential for breeding in many birds, and differ widely in morphology across species. Only a few bird species build compound nests, with different nest chambers as part of a continuous structure. Knowing the ecological and social conditions leading to compound nest construction in species where this behaviour is not the norm can improve o...

Red coloration is a salient feature of the natural world. Many vertebrates produce red color by converting dietary yellow carotenoids into red ketocarotenoids via an unknown mechanism. Here, we show that two enzymes, cytochrome P450 2J19 (CYP2J19) and 3-hydroxybutyrate dehydrogenase 1-like (BDH1L), are sufficient to catalyze this conversion. In bir...

Dominance hierarchies are known to reduce agonistic interactions between individuals and may be influenced by differences in phenotypes such as body size, personality or cognition. Colour ornamentation, especially with melanin-based colours, can also be a badge of status signalling social dominance, but status signalling with carotenoid-based colou...

Sex differences in ornamentation are common and, in species with conventional sex roles, are generally thought of as stable, due to stronger sexual selection on males. Yet, especially in gregarious species, ornaments can also have non-sexual social functions, raising the possibility that observed sex differences in ornamentation are plastic. For ex...

Biological invasions may involve species colonising different climatic regions than those in their native ranges, and it is not straightforward to predict how breeding phenology changes in the invasive ranges. The common waxbill Estrilda astrild is one of the most widespread invasive birds worldwide. It is an opportunistic breeder, adapted to trans...

Birds exhibit striking variation in eye color that arises from interactions between specialized pigment cells named chromatophores. The types of chromatophores present in the avian iris are lacking from the integument of birds or mammals, but are remarkably similar to those found in the skin of ectothermic vertebrates. To investigate molecular mech...

Sex differences in ornamentation are common and, in species with conventional sex roles, are generally thought of as fixed, due to stronger sexual selection on males. Yet, especially in gregarious species, ornaments can also have non-sexual social functions, raising the possibility that observed sex differences in ornamentation are not fixed. For e...

Stress is known to modulate behavioral responses and rapid decision-making processes, especially under challenging contexts which often occur in social and cooperative interactions. Here, we evaluated the effects of acute stress on cooperative behavior of the Indo-Pacific cleaner wrasse (Labroides dimidiatus) and the implications of pre-treatment w...

Canaries changing colors Many animals are sexually dimorphic, with different phenotypes in males and females. To identify the genetic basis of sexual differences in bird coloration, Gazda et al. investigated red coloration in mosaic canaries and related species (see the Perspective by Chen). Using a combination of genetic crosses, genomic mapping,...

Reactive individuals explore and make decisions more slowly than proactive individuals, paying more attention to external cues. Reactive personality types are therefore predicted to make fewer mistakes in cognitive tasks, especially in tests of inhibitory control and reversal learning that require individuals to adjust behavioral routines. However,...

There is increasing interest on the genetic and physiological bases of behavioural differences among individuals, namely animal personality. One particular dopamine (DA) receptor gene (the dopamine receptor D4 gene) has been used as candidate gene to explain personality differences, but with mixed results. Here we use an alternative approach, exoge...

Discrete colour morphs coexisting within a single population are common in nature. In a broad range of organisms, sympatric colour morphs often display major differences in other traits, including morphology, physiology or behaviour. Despite the repeated occurrence of this phenomenon, our understanding of the genetics that underlie multi-trait diff...

Sexual signals often compromise camouflage because of their conspicuousness. Pigmentation patterns, on the contrary, aid in camouflage. It was hypothesized that a particular type of pattern—barred plumage in birds, whereby pigmented bars extend across feathers—could simultaneously signal individual quality, because disruptions of these patterns sho...