Sexual selection for single song repertoires.

Despite birdsong being one of the most studied models of sexual selection, how it operates in birds that sing only one song remains poorly understood. A recent study using a big data approach reveals a novel aspect of song that may potentially function as an honest signal of male quality and a way to maintain listener attention.

An Interactive Feeder to Induce and Assess Emotions from Vocalisations of Chickens.

Understanding the emotional states of animals is a long-standing research endeavour that has clear applications in animal welfare. Vocalisations are emerging as a promising way to assess both positive and negative emotional states. However, the vocal expression of emotions in birds is a relatively unexplored research area.

Early life conditions reduce similarity between reproductive partners in HPA axis response to stress.

Social environments modulate endocrine function, yet it is unclear whether individuals can become like their social partners in how they physiologically respond to stressors. This social transmission of hypothalamic-pituitary-adrenal (HPA) axis reactivity could have long-term consequences for health and lifespan of individuals if their social partners react to stressors with an exaggerated HPA axis response. We tested whether glucocorticoid levels in response to stress of breeding partners changes after breeding depending on whether partners had similar or dissimilar postnatal conditions.

The multi-dimensional nature of vocal learning.

How learning affects vocalizations is a key question in the study of animal communication and human language. Parallel efforts in birds and humans have taught us much about how vocal learning works on a behavioural and neurobiological level. Subsequent efforts have revealed a variety of cases among mammals in which experience also has a major influence on vocal repertoires.

Learning strategies and the social brain: Missing elements in the link between developmental stress, song and cognition?

Bird songs may advertise aspects of cognition because song learning and learning speed in cognitive tasks are both affected by early-life environments. However, such relationships remain ambiguous in the literature. Here, I discuss 2 lines of research that may help to demystify links between song learning and cognition.

Vocal tract constancy in birds and humans.

Humans perceive speech as being relatively stable despite acoustic variation caused by vocal tract (VT) differences between speakers. Humans use perceptual 'vocal tract normalisation' (VTN) and other processes to achieve this stability. Similarity in vocal apparatus/acoustics between birds and humans means that birds might also experience VT variation.

Directional Asymmetries in Vowel Perception of Adult Nonnative Listeners Do Not Change Over Time With Language Experience.

Purpose: This study tested an assumption of the Natural Referent Vowel (Polka & Bohn, 2011) framework, namely, that directional asymmetries in adult vowel perception can be influenced by language experience.

Method: Data from participants reported in Escudero and Williams (2014) were analyzed. Spanish participants categorized the Dutch vowels /aː/ and /ɑ/ in 2 separate sessions: before and after vowel distributional training.