Search results for "TSH"

Sexual advertisement and immune function in an arachnid species (Lycosidae)

2004

A simple version of the immunocompetence handicap hypothesizes that through condition-dependence, the size of the sexual trait may be positively related to immune function at the population level. In the present study, we investigated the relationship between sexual advertisement and immune function in a natural population of male wolf spiders, Hygrolycosa rubrofasciata (Araneae: Lycosidae). Males of H. rubrofasciata have a costly and condition-dependent acoustic signal, courtship drumming. In the mating season, males drum against dry leaves while wandering around the habitat searching for receptive females. Males increase their mating success by increasing their drumming rate and mobility.…

L’uso del hrTSH nel follow up del microcarcinoma tiroideo in pazienti sottoposti a tiroidectomia totale

2004

The effect of social information from live demonstrators compared to video playback on blue tit foraging decisions.

2019

Video playback provides a promising method to study social interactions, and the number of video playback experiments has been growing in recent years. Using videos has advantages over live individuals as it increases the repeatability of demonstrations, and enables researchers to manipulate the features of the presented stimulus. How observers respond to video playback might, however, differ among species, and the efficacy of video playback should be validated by investigating if individuals’ responses to videos are comparable to their responses to live demonstrators. Here, we use a novel foraging task to compare blue tits’ (Cyanistes caeruleus) responses to social information from a live …

A glial amino-acid transporter controls synapse strength and courtship in Drosophila

2008

1097-6256 (Print) Journal Article Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't; Mate choice is an evolutionarily critical decision that requires the detection of multiple sex-specific signals followed by central integration of these signals to direct appropriate behavior. The mechanisms controlling mate choice remain poorly understood. Here, we show that the glial amino-acid transporter genderblind controls whether Drosophila melanogaster males will attempt to mate with other males. Genderblind (gb) mutant males showed no alteration in heterosexual courtship or copulation, but were attracted to normally unappealing male species-specific chemosensory cues. As a resul…

Evidence for sex pheromones produced by males and females inBlatta orientalis (Dictyoptera, Blattidae).

1993

Males and females ofBlatta orientalis produce a volatile sex pheromone attractive at a distance. The male initiates courtship behavior by adopting a calling posture while emitting his sex pheromone. He exposes the anterior region of his tergites by stretching his abdomen horizontally. Morphological observations show the existence of male tergal glands on the anterior region of tergites 1 to 8. Behavioral assays of females utilizing methylene chloride extracts of various male body parts reveal that extracts of the anterior region of tergites are highly attractive and induce more positive responses that any other body part. Once near the male, the attracted female opens widely her genital atr…

Courtship behaviour of Drosophila melanogaster revisited

2006

0003-3472 doi: DOI: 10.1016/j.anbehav.2006.01.027; Nearly all studies of Drosophila melanogaster courtship have focused exclusively on male behaviour. Female precopulatory behaviour is often relegated to ‘accept' or ‘reject' mating, and how female behaviour interacts with that of males remains largely unknown. Using a video-computing approach, we measured 10 behavioural states and 22 elementary behaviours that occur during the precopulatory phase of Canton-S (Cs) flies. Male and female behaviours were studied under a variety of social conditions. This allowed us to identify which one(s) is relevant to courtship or to general activity. Our analysis showed that the courtship repertoire was no…

Decreased sexual signalling reveals reduced viability in small populations of the drumming wolf spider Hygrolycosa rubrofasciata.

2004

One of the important goals in conservation biology is to determine reliable indicators of population viability. Sexual traits have been suggested to indicate population extinction risk, because they may be related to viability through condition dependence. Moreover, condition-dependent sexual traits may be more sensitive indicators of population viability than early life-history traits, because deleterious fitness effects of inbreeding tend to be expressed mainly at the end of the species' life history. However, empirical evidence of the significance of sexual behaviour for population viability is missing. In this study, we examined two male sexual traits and survival in 39 different-sized …

Pheromonal emission during the mating behavior ofEurycotis floridana (Walker) (Dictyoptera: Blattidae)

1996

The sexual behavior of males and females ofEurycotis floridana was investigated and the various associated behavioral sequences are described. Olfactometer data proved that the male produces a volatile sex pheromone attractive at a distance to conspecific females. The male initiates courtship behavior by exposing the glandular areas on the anterior parts of abdominal tergites 2, 7, and 8. This male calling behavior was observed throughout the day. The males can mate when 8 days old, whereas virgin females are sexually receptive 18 days after becoming adults. Once attracted near the male, the female opens her genital atrium and climbs on the back of the male, where she feeds on the glandular…

Testing the assumptions of conditional handicap theory: costs and condition dependence of a sexually selected trait

2000

Conditional handicap models of sexual selection predict that sexual traits are reliable signals of male quality because they are (a) condition dependent and (b) costly to produce or maintain. In this study, my objective was to experimentally investigate whether the drumming of male Hygrolycosa rubrofasciata wolf spiders is a condition-dependent costly trait. Males court females by drumming dry leaves with their abdomen and females preferentially mate with males drumming at higher rates. I manipulated male phenotypic condition and drumming rate simultaneously by keeping males on three different food rations and either introducing or not introducing them to a female. Food ration treatment aff…

In situ behavior of wild long-snouted seahorse Hippocampus guttulatus Cuvier, 1829

2021

The study of behavior is one of the fundamental aspects of conservation biology. While for animals such as mammals there are well-defined protocols that have been applied for a long time, for marine animals, and fish in particular, studies are available for a limited number of species. The behavior of seahorses, for example, is poorly studied and in this work, we made a first attempt of using video recordings to analyze behavior of these endangered species in Mar Piccolo of Taranto (Southern Italy). The study presents preliminary data on behavioral activities and their comparisons among different life stages of Hippocampus guttulatus, namely females, males, and juveniles. Juveniles and fema…