Search results for "THS"
showing 10 items of 696 documents
Memorializing mass deaths at the border: two cases from Canberra (Australia) and Lampedusa (Italy)
2017
In this paper, we compare two seemingly very similar instances in which individuals and organizations within the borders of the global North have memorialized the deaths of irregular migrants at sea: the SIEV X memorial in Australia’s national capital Canberra, and the Giardino della memoria (Garden of Remembrance) on the Italian island of Lampedusa. Unlike ephemeral manifestations of grief, potentially these memorials have effects that reach well beyond their creation. We relate the differences between the memorials to the contexts within which they were created: an immediate local response involving people directly affected by the disaster’s aftermath, on the one hand, and a delayed natio…
Digital generations, but not as we know them
2019
The aim of this article is to see whether or not adolescents were the real leaders of the digital ‘revolution’ in the 1990s and whether they have sustained or even improved their position in the 2000s. The analysis is based on two surveys carried out in Italy, France, the United Kingdom, Germany, and Spain in 1996 ( N = 6609) and in 2009 ( N = 7255). The results show that the adolescents belonging to the first digital generation in 1996 were the most equipped with new technologies, although not the most intensive users. In 2009, the adolescents lost their position as the leading adopters and lagged behind youth and young adults regarding the use of new technologies and computer skills.
Helminth Infection of the Loggerhead Sea Turtle Caretta caretta along the Coasts of Sicily and the North West Adriatic Sea
2021
We provide new data on the presence of helminth parasites in 64 individual loggerhead sea turtles Caretta caretta stranded along the coasts of Sicily and the northwest Adriatic Sea between June 2014 and August 2016. The necropsy examination revealed 31 individuals (48.4%) positive for endoparasites, showing a greater prevalence of trematodes than nematodes. In particular, seven species and a single genus of Trematoda (Hapalotrema) and a single species and genus of Nematoda (Kathlania) were identified. Among the Digenea flukes the species with the highest prevalence of infection were Rhytidodes gelatinosus (34.6%) and Hapalotrema sp. (33.3%), while among the Nematoda they were Kathlania sp. …
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…
An aposematic colour‐polymorphic moth seen through the eyes of conspecifics and predators – Sensitivity and colour discrimination in a tiger moth
2018
Although predation is commonly thought to exert the strongest selective pressure on coloration in aposematic species, sexual selection may also influence coloration. Specifically, polymorphism in aposematic species cannot be explained by natural selection alone. Males of the aposematic wood tiger moth (Arctia plantaginis) are polymorphic for hindwing coloration throughout most of their range. In Scandinavia, they display either white or yellow hindwings. Female hindwing coloration varies continuously from bright orange to red. Redder females and yellow males suffer least from bird predation. White males often have higher mating success than yellow males. Therefore, we ask whether females ca…
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. …
Heterozygote advantage and pleiotropy contribute to intraspecific color trait variability
2022
The persistence of intrapopulation phenotypic variation typically requires some form of balancing selection because drift and directional selection eventually erode genetic variation. Heterozygote advantage remains a classic explanation for the maintenance of genetic variation in the face of selection. However, examples of heterozygote advantage, other than those associated with disease resistance, are rather uncommon. Across most of its distribution, males of the aposematic moth Arctia plantaginis have two hindwing phenotypes determined by a heritable one locus-two allele polymorphism (genotypes: WW/Wy = white morph, yy = yellow morph). Using genotyped moths, we show that the presence of o…
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…
Author Correction: Evaluation of three methods for biomass estimation in small invertebrates, using three large disparate parasite species as model o…
2018
Invertebrate biomass is considered one of the main factors driving processes in ecosystems. It can be measured directly, primarily by weighing individuals, but more often indirect estimators are used. We developed two indirect and non-destructive approaches to estimate biomass of small invertebrates in a simple manner. The first one was based on clay modelling and the second one was based on image analysis implemented with open-source software. Furthermore, we tested the accuracy of the widely used geometric approximation method (third method). We applied these three different methods to three morphologically disparate model species, an acanthocephalan worm, a crustacean and a flatworm. To …
Liiketoimintaverkostoon vaikuttavat tekijät - teknologinen näkökulma
2013
Tutkielmassa tutkitaan liiketoimintaverkostoja ja siihen vaikuttavia tekijöitä, erityisesti teknologian näkökannalta. Liiketoimintaverkostolla tarkoitetaan verkostoa jossa toimii useampi yritys ja joita sitoo toisiinsa erilaiset suhteet. Teknologialla tarkoitetaan tutkielmassa kaikkea teknologiaa jota käytetään muun muassa informaation eri muotojen luomiseen, tallennukseen, kommunikointiin ja käyttöön. Tarkemmin on tarkasteltu internettiä ja sitä hyödyntäviä teknologioita kuten sähköpostia, videoneuvottelua ja erilaisia IOS-järjestelmiä sekä digitalisaatiota. Tutkielman tutkimuskysymyksiä tarkasteltiin liiketoimintaverkoston kolmen myytin ja kolmen paradoksin teorioiden kautta. Tutkimuksen …