Evolution of acoustic and visual signals in the antwrens of the tribe Formicivorini (Aves, Thamnophilidae)

Author(s)

Renata Pereira Beco

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB)
• Defense date: 2018-10-26

Examining board members

Luis Fábio Silveira; Gustavo Burin Ferreira; Lilian Tonelli Manica

• Advisor: Luis Fábio Silveira

Abstract

Animal communication transmits information using different sensory signals that have particular purposes (e.g. courtship, territorial defense, maintaining groups together and minimizing predation) and are susceptible to habitat pressures (Sensory Drive Hypothesis - SDH). In birds, some studies on acoustic and visual signals showed that song structure is associated with sound transmission capacity in different habitats and some plumage features (e.g. color, brightness and pattern) seem to vary according to light conditions of the environment. In addition to habitat effects, other factors such as energetic limits, predation, and parasitism risk can limit the investment in more than one type of sensory signal. Due to this high cost, it was proposed the existence of an evolutionary trade-off between the different types of sensory signals termed Transfer (TH) or Trade-off hypothesis. Few studies that have tested the TH in birds showed contrasting results, being corroborated only in two studies. Also, there is a low in the number of studies that have considered habitat conditions as covariates (SDH). Here, we assess the TH between acoustic and visual signals, while simultaneously considering potential effects of habitat conditions (SDH) in a diverse group of Neotropical suboscine birds, commonly known as antbirds (Thamnophilidae). Specifically, we integrated a genome-scale phylogeny of the tribe Formicivorini (36 species) with vocal, plumage, ecological, and behavioral data within a phylogenetic comparative framework to simultaneously test the TH and SDH while assessing the influence of mixed-species flocking foraging behavior on the structural diversity of acoustic and visual signals. Whereas in both sexes we found significant trade-offs between some plumage and vocal traits (e.g. dorsal luminance versus frequency slope), providing support for the TH, we found a non-significant opposite trend between plumage and vocal sexual dimorphism. All these relationships are influenced by habitat conditions and behavioral traits as covariates, corroborating the SDH and mixed-species flocking behavior influence in the evolution of visual and acoustic signals (AU)

• FAPESP's process: 16/08814-5 - Evolution of acoustic and visual signals in the thamnophilids of the tribe Formicivorini (Aves: Passeriformes)
• Grantee: Renata Pereira Beco
• Support Opportunities: Scholarships in Brazil - Master