The signalling function of melanin‐based colouration is debated. Sexual selection theory
states that ornaments should be costly to produce, maintain, wear or display to signal quality …

The uropygial gland is a holocrine complex exclusive to birds that produces an oleaginous
secretion (preen oil) whose function is still debated. Herein, I examine critically the evidence …

Biomonitoring using birds of prey as sentinel species has been mooted as a way to evaluate
the success of European Union directives that are designed to protect people and the …

Although a growing body of evidence supports that olfaction based on chemical compounds
emitted by birds may play a role in individual recognition, the possible role of chemical cues …

Feathers have many advantages that make them an excellent nondestructive tool for
monitoring polyhalogenated compounds (PHCs). This paper proposes a review on the …

Parasites and other symbionts are crucial components of ecosystems, regulating host
populations and supporting food webs. However, most symbiont systems, especially those …

Much of the growing interest in avian chemical signals has focused on the role of kin
recognition or mate attraction, often with an emphasis on males, with uropygial gland …

Potentially, pathogenic bacteria are one of the main infective agents against which a battery
of chemical and physical barriers has evolved in animals. Among these are the secretions …

The preen gland is a holocrine sebaceous gland of the avian integument which produces an
oily secretion that is spread on the plumage during preening. It has been suggested that …

Feather mites are arthropods that live on or in the feathers of birds, and are among the
commonest avian ectosymbionts. However, the nature of the ecological interaction between …