Condition dependence

We examined the preference of Atlantic molly females (Poecilia mexicana) to associate with a well-fed or a starved male in simultaneous choice tests. Females from three different populations were tested in three treatments: (1) the females could choose on the basis of multiple cues from the males (visual plus non-visual); (2) only non-visual cues could be perceived in darkness, (3)

We consider a multiobject detection problem over a sensor network (SNET) with limited range multimodal sensors. The general problem complements the widely considered decentralized detection problem where all sensors observe the same object. We develop a distributed detection approach based on recent development of the false discovery rate (FDR) and the associated Benjamini-Hochberg (BH) procedure, which rank orders scalar test

Abstract. In this paper we present a new model for the requirements analysis of a system. We offer a conceptual model defined following a visual modeling lan-guage, called dependence networks. TROPOS uses a visual modeling language called dependence networks in the ...

Solder joints are subjected to different loading conditions depending on the application environment. Desktop and server applications for example, involve thermomechanical fatigue loads at low-strain rates and the dominant mode of failure is creep fatigue. Mobile electronics applications on the other hand, are subject to dynamic stresses on the solder joint during impact. In our previous work, we developed a

Epithiospecifier protein (ESP), a ferrous ion depen- dent protein, has a potential role in regulating the release of elemental sulphur, nitriles, isothiocyanates and cyanoepithioalk- anes from glucosinolates. Two classes of ESP polypeptides were purified with molecular masses of 39 and 35 kDa, and we show that the previously reported instability was conditionally dependent. The 39 kDa polypeptide was made up

This paper proposes a new planning approach that authorizes an autonomous robot to reason about the inaccuracy of the world description and of its possible evolutions. We represent the uncertainty with the possibility theory; this al­ lows us to distinguish between two types of non- determinism: a non-determinis m from insuf­ ficient modeling and a non-determinis m from uncertainty. Besides,

We explore the use of genetic algorithms to directly evolve classification decision trees. We argue on the suitability of such a concept learner due to its ability to efficiently search complex hypotheses spaces and discover conditionally dependent as well as irrelevant attributes. The performance of the system is measured on a set of artificial and standard discretized concept-learning problems and compared with the performance of two known algorithms (C4. 5, OneR). We demonstrate that the derived hypotheses of standard ...

The evolution of conspicuous coloration is often hypothesized to be driven by sexual selection, where colour traits may function as honest signals of individual abilities in male contest competition and female choice. However, game theory models suggest that colourful badges (i.e. energetically cheap signals) may have no function in sexually selected contests, because the value of the contested resource is too high relative to the costs of fighting. We investigated this assertion by experimentally staging male contests over nest sites (a crucial resource for attracting females) in old (>/=2 years) male collared flycatchers, Ficedula albicollisMales with a relatively large white forehead patch (i.e. a condition-dependent plumage trait displayed in male contests) enjoyed a competitive advantage in disputes over experimentally vacated territories. No other measured morphological variable predicted the outcome of such a dispute. Furthermore, the winners of the disputes acquired a female more quickly than did the losers. Thus, our results suggest that the white forehead patch of male collared flycatchers may function as a badge of status that is also used in sexually selected contests over resources. We suggest that this is because the value of the contested territory may be relatively low compared with the cost of fighting when alternative vacant sites exist in the neighbourhood.Copyright 1997 The Association for the Study of Animal Behaviour1997The Association for the Study of Animal Behaviour

Hormones play a crucial role in mediating genetic and environmental effects into morphological and behavioral phenotypes. In systems with alternative reproductive tactics (ART) shifts between tactics are hypothesized to be under proximate hormonal control. Most studies of the underlying endocrine changes behind ART have focused on fish and amphibians rather than mammals and few have investigated the potential interaction between different endocrine axes in regulating shifts between conditional dependent tactics. Using a combination of endocrine and behavioral data from male African elephants we expand on our previously published analysis and show that the initial increase in androgens predates the behavioral shifts associated with reproductively active periods, supporting the role of androgens in activating sexually active periods in males. A strong interactive effect between androgens and glucocorticoids was found to determine the presence or absence of temporal gland secretion and urine dribbling, signals associated with the competitive reproductive tactic of musth, with elevated glucocorticoids levels suppressing the occurrence of musth signals. In addition external environmental conditions affected hormone levels. The presence of receptive females resulted in elevated androgens in dominant musth males but increased glucocorticoids in subordinate non-musth males. The presented data on hormones, behavior and reproductive tactics strongly support an underlying endocrine mechanism for mediating the translation of intrinsic as well as extrinsic local conditions into the conditional dependent reproductive tactics in male elephants via interactions between the hypothalamic-pituitary-gonadal and -adrenal axes.