Leaf anatomy explains the strength of C activity within the grass species Alloteropsis semialata.

C photosynthesis results from anatomical and biochemical characteristics that together concentrate CO around ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), increasing productivity in warm conditions. This complex trait evolved through the gradual accumulation of components, and particular species possess only some of these, resulting in weak C activity. The consequences of adding C components have been modelled and investigated through comparative approaches, but the intraspecific dynamics responsible for strengthening the C pathway remain largely unexplored.

The genetic basis of structural colour variation in mimetic butterflies.

Structural colours, produced by the reflection of light from ultrastructures, have evolved multiple times in butterflies. Unlike pigmentary colours and patterns, little is known about the genetic basis of these colours. Reflective structures on wing-scale ridges are responsible for iridescent structural colour in many butterflies, including the Müllerian mimics and Here, we quantify aspects of scale ultrastructure variation and colour in crosses between iridescent and non-iridescent subspecies of both of these species and perform quantitative trait locus (QTL) mapping.

Upregulation of C characteristics does not consistently improve photosynthetic performance in intraspecific hybrids of a grass.

C photosynthesis is thought to have evolved via intermediate stages, with changes towards the C phenotype gradually enhancing photosynthetic performance. This hypothesis is widely supported by modelling studies, but experimental tests are missing. Mixing of C components to generate artificial intermediates can be achieved via crossing, and the grass Alloteropsis semialata represents an outstanding study system since it includes C and non-C populations.

Hybridization boosts dispersal of two contrasted ecotypes in a grass species.

Genetic exchanges between closely related groups of organisms with different adaptations have well-documented beneficial and detrimental consequences. In plants, pollen-mediated exchanges affect the sorting of alleles across physical landscapes and influence rates of hybridization. How these dynamics affect the emergence and spread of novel phenotypes remains only partially understood.

Low dispersal and ploidy differences in a grass maintain photosynthetic diversity despite gene flow and habitat overlap.

Geographical isolation facilitates the emergence of distinct phenotypes within a single species, but reproductive barriers or selection are needed to maintain the polymorphism after secondary contact. Here, we explore the processes that maintain intraspecific variation of C photosynthesis, a complex trait that results from the combined action of multiple genes. The grass Alloteropsis semialata includes C and non-C populations, which have coexisted as a polyploid series for more than 1 million years in the miombo woodlands of Africa.

Contrasted histories of organelle and nuclear genomes underlying physiological diversification in a grass species.

C photosynthesis evolved multiple times independently in angiosperms, but most origins are relatively old so that the early events linked to photosynthetic diversification are blurred. The grass is an exception, as this species encompasses C and non-C populations. Using phylogenomics and population genomics, we infer the history of dispersal and secondary gene flow before, during and after photosynthetic divergence in .

Müllerian mimicry of a quantitative trait despite contrasting levels of genomic divergence and selection.

Hybrid zones, where distinct populations meet and interbreed, give insight into how differences between populations are maintained despite gene flow. Studying clines in genetic loci and adaptive traits across hybrid zones is a powerful method for understanding how selection drives differentiation within a single species, but can also be used to compare parallel divergence in different species responding to a common selective pressure. Here, we study parallel divergence of wing colouration in the butterflies Heliconius erato and H.

Phenotypic variation in crosses shows that iridescent structural colour is sex-linked and controlled by multiple genes.

Bright, highly reflective iridescent colours can be seen across nature and are produced by the scattering of light from nanostructures. butterflies have been widely studied for their diversity and mimicry of wing colour patterns. Despite iridescence evolving multiple times in this genus, little is known about the genetic basis of the colour and the development of the structures which produce it.

Wing scale ultrastructure underlying convergent and divergent iridescent colours in mimetic butterflies.

Iridescence is an optical phenomenon whereby colour changes with the illumination and viewing angle. It can be produced by thin film interference or diffraction. Iridescent optical structures are fairly common in nature, but relatively little is known about their production or evolution.