Pharmacometabolomics of Response to Sertraline and to Placebo in Major Depressive Disorder - Possible Role for Methoxyindole Pathway

10.1371/journal.pone.0068283PLoS ONE87-POLN

Anatomy of avian distress calls: Structure, variation, and complexity in two species of shorebird (Aves: Charadrii)

Abstract Birds often vocalize when threatened or captured by a predator. We present detailed qualitative analyses of calls from 24 red-capped plover (Charadrius ruficapillus) and 117 masked lapwing (Vanellus miles) chicks (Charadriidae) that we recorded during handling. Calls were structurally complex and differed between species. Calls showed moderate structure at higher levels of organization (e.g., similarity between successive calls; sequential grading). Some call characteristics resembled those in other bird species in similar circumstances (e.g., in nonlinear phenomena). Most calls consisted of several different parts, which combined in different ways across calls. Past studies have overlooked most features of distress calls and calling in charadriids due to small sample sizes and limited spectrographic analyses. Understanding interspecific patterns in call structure, and determination of call functions, will require: detailed knowledge of natural history; detailed behavioural descriptions, acoustic analysis, and analyses of development and growth; and experimental investigations of call functions.</jats:p

Experiment_Kostoglou_et_al_2017

See the ReadMe file. This file contains the results of the experimental part of the study

Vocal traits of shorebird chicks are related to body mass and sex

Acoustic communication is critical during early life phases in precocial birds; for example, adult alarm calls can elicit antipredator behaviour in young, and chick vocalizations can communicate information to parents about chick identity, condition, location, sex or age. We opportunistically recorded Red-capped Plover Charadrius ruficapillus and Southern Masked Lapwing Vanellus miles novaehollandiae distress calls of chicks while they were in the hand and analysed the calls to determine whether call structure is related to sex or body mass (a proxy for age). Our study provides the first evidence for charadriid chicks of (1) a sexual difference in call structure and rate and (2) gradual growth-related changes in call structure and rate, across chicks. We provide a foundation for further studies of shorebird vocalizations during growth, which may elucidate the development and functional significance of such vocalizations

Lees_Plover_parents_care_more_for_young_of_the_opposite_sex_data

A single .xlxs file containing two tabs. The first tab contains the data from the analysis of parental care, the second contains data from chick survival

Data from: Acoustic cues from within the egg do not heighten depredation risk to shorebird clutches

Egg predators use an array of olfactory and visual cues to locate eggs. Precocial avian embryos within eggs can produce vocalizations for a period prior to hatching, which may be audible to predators. Here, we investigated, under field conditions, the embryonic vocalizations emitted from eggs of a shorebird species, the Red-capped Plover Charadrius ruficapillus. We characterize the acoustic properties of the vocalizations and the circumstances under which they are emitted, then test whether such vocalizations are used as an acoustic cue by predators to locate eggs. Embryonic vocalizations typically occurred between 0 and 5 days before hatching (henceforth the “vocalization period”). Within the vocalization period, the maximum acoustic frequency (kHz) of vocalizations increased with egg age (perhaps as a consequence of embryonic development) and the minimum acoustic frequency (kHz) increased with ground temperature (perhaps as mode of communication with parents regarding thermal needs). An artificial nest experiment compared the survival of nests with and without acoustic cues (prerecorded embryonic vocalizations played continuously from the nest). Corvids were the major egg predator (accounting for 76% of cases of artificial nest predation). However, the presence of vocalizations did not affect the time taken for predators to locate and depredate eggs. Our results suggest that embryonic vocalizations are important signals that may aid in communication with parents but that they do not increase predation rates. Further research involving a greater diversity of predators (e.g., acoustic predators) is required to examine whether vocalizations from the egg incur costs under other predator regimes