Search results for "Signals"
showing 8 items of 128 documents
Putative sorting signals involved in PIN1 trafficking
2013
Las auxinas son hormonas vegetales involucradas en muchos procesos fisiológicos, tales como el crecimiento y diferenciación celular, la maduración de los frutos, la floración o los tropismos. Su transporte a través de la planta es polar, jugando un papel esencial en la regulación del crecimiento y el desarrollo y contribuyendo al mantenimiento de la polaridad global de la planta. La polaridad en el flujo de auxinas es debida, al menos en parte, a la distribución polar de los transportadores de salida de auxina de la familia PIN. En Arabidopsis thaliana se han identificado 8 transportadores PIN diferentes. Todos ellos presentan una estructura similar, con un dominio citosólico central que se…
Colour alone matters : no predator generalization among morphs of an aposematic moth
2018
Local warning colour polymorphism, frequently observed in aposematic organisms, is evolutionarily puzzling. This is because variation in aposematic signals is expected to be selected against due to predators' difficulties associating several signals with a given unprofitable prey. One possible explanation for the existence of such variation is predator generalization, which occurs when predators learn to avoid one form and consequently avoid other sufficiently similar forms, relaxing selection for monomorphic signals. We tested this hypothesis by exposing the three different colour morphs of the aposematic wood tiger moth, Arctia plantaginis, existing in Finland to local wild-caught predato…
Multimodal Aposematic Defenses Through the Predation Sequence
2021
Aposematic organisms warn predators of their unprofitability using a combination of defenses, including visual warning signals, startling sounds, noxious odors, or aversive tastes. Using multiple lines of defense can help prey avoid predators by stimulating multiple senses and/or by acting at different stages of predation. We tested the efficacy of three lines of defense (color, smell, taste) during the predation sequence of aposematic wood tiger moths (Arctia plantaginis) using blue tit (Cyanistes caeruleus) predators. Moths with two hindwing phenotypes (genotypes: WW/Wy = white, yy = yellow) were manipulated to have defense fluid with aversive smell (methoxypyrazines), body tissues with a…
Safety in Numbers: How Color Morph Frequency Affects Predation Risk in an Aposematic Moth
2021
Polymorphic warning signals in aposematic systems are enigmatic because predator learning should favor the most common form, creating positive frequency-dependent survival. However, many populations exhibit variation in warning signals. There are various selective mechanisms that can counter positive frequency-dependent selection and lead to temporal or spatial warning signal diversification. Examining these mechanisms and their effects requires first confirming whether the most common morphs are favored at both local and regional scales. Empirical examples of this are uncommon and often include potentially confounding factors, such as a lack of knowledge of predator identity and behavior. …
Influence of colour, smell and taste on the survival of the wood tiger moth (Arctia plantaginis) adults during predation event
2021
Saalistajien torjumiseksi saalis voi käyttää erilaisia puolustusmekanismeja, jotka stimuloivat useita eri aisteja (ts. multimodaalista signalointia). Esimerkiksi aposemaattiset eliöt puolustautuvat varoitussignaalin lisäksi sekundaarisella puolustuksella. Tässä tutkimuksessa keskityttiin siihen, kuinka täpläsiilikkään (Arctia plantaginis) väritys (genotyypit WW, Wy ovat valkoisia ja yy keltaisia), haju (metoksipyratsiinista) ja maku (pyrrolitsidiinialkaloidista) toimivat puolustuksena lintusaalistajien hyökkäyksiä vastaan. Linnuille tarjottiin kummankin värisiä eläviä siilikkäitä, joita oli manipuloitu niin, että niillä oli joko hajua, makua tai molempia näistä. Näin pystyttiin tutkimaan ku…
Multimodal Aposematic Signals and Their Emerging Role in Mate Attraction
2018
Multimodal Aposematic Signals and Their Emerging Role in Mate Attraction
2018
Chemically defended animals often display conspicuous color patterns that predators learn to associate with their unprofitability and subsequently avoid. Such animals (i.e., aposematic), deter predators by stimulating their visual and chemical sensory channels. Hence, aposematism is considered to be “multimodal.” The evolution of warning signals (and to a lesser degree their accompanying chemical defenses) is fundamentally linked to natural selection by predators. Lately, however, increasing evidence also points to a role of sexual selection shaping warning signal evolution. One of the species in which this has been shown is the wood tiger moth, Arctia plantaginis, which we here put forward…
System wczesnego ostrzegania w zarządzaniu projektami jako narzędzie wspomagania osiągania sukcesu projektu
2020
Celem artykułu jest zaprezentowanie istoty systemów wczesnego ostrzegania w zarządzaniu projektami w kontekście osiągania celów projektów. Potrzeba stosowania narzędzi wczesnego ostrzegania w zarządzaniu projektami ma uzasadnienie przede wszystkim w fakcie, że z reguły (pomijając zdarzenia nadzwyczajne) przedsiębiorstwa wykazują objawy sytuacji kryzysowych w realizacji podejmowanych projektów na długo przedtem zanim dojdzie do niepowodzenia projektu. Wczesne zidentyfikowanie sygnałów zbliżającego się kryzysu powinno być zatem jednym z podstawowych zadań w zarządzaniu projektami. W artykule omówiono rolę systemu wczesnego ostrzegania oraz jego funkcje. Wskazano na zastosowania systemów wczes…