Exposure to a competitive social environment activates an epigenetic mechanism that limits pheomelanin synthesis in zebra finches

Competitive environments promote high testosterone levels, oxidative stress and, consequently, impair cellular homeostasis. The regulation of genes involved in the synthesis of the pigment pheomelanin in melanocytes seems to help to maintain homeostasis against environmental oxidative stress. Here, social interactions in some zebra finch Taeniopygia guttata males were experimentally increased by keeping them in groups of six birds during feather growth, while others were kept alone, to test...

Avian malaria parasites reduce the survival of mosquitoes

Plasmodium transmission success depends upon the trade-off between the use of host resources to favour parasite reproduction and the negative effects on host health, which can be mediated by infection intensity. Despite its potential influence on parasite dynamics, the effects of infection intensity on both, birds and vectors, and on Plasmodium transmission success are still poorly understood. Here, the Plasmodium load in naturally infected wild house sparrows was experimentally reduced with...

Explaining path dependent rigidity traps: increasing returns, power, discourses and entrepreneurship intertwined in social-ecological systems

The current, unprecedented rate of human development is causing major damages to Earth’s life-support systems. Therefore, the need for transitions towards sustainability in the use of natural resources and ecosystems has been extensively advocated. To be successful, such transitions must be guided by a sound understanding of the architecture of the policy and institutional designs of both the process of change and the target outcome.

The invasive red swamp crayfish increases infection of the amphibian chytrid fungus

Chytridiomycosis, caused by Batrachochytrium dendrobatidis (Bd), is considered one of the most important causes for the decline of amphibian populations worldwide. Identifying potential biological reservoirs and characterizing the role they can play in pathogen maintenance is not only important from a scientific point of view, but also relevant from an applied perspective (e.g. disease control strategies), especially when worldwide distributed invasive species are involved.

“Planned obsolescence” in the plumage of larks

Larks (Alaudidae) present a heavily worn plumage for the most part of the annual cycle. Authors observed that lark feathers have unmelanized fringes and are prone to breakage. Larks may have turned need into a virtue: they possibly cannot avoid a premature damage of their fragile plumage, and instead of incurring the cost of molting repeatedly, they gain the advantage of a form of crypsis known as disruptive camouflage.