Anecdotal evidence suggests that lekking birds exhibit considerable variation in form and degree of sociality away from the lek, yet this phenomenon has received very little theoretical or empirical ...research attention. Here, we provide the first synthetic literature review of off-lek sociality in birds and develop a conceptual framework for the potential adaptive function of off-lek sociality across lekking taxa. We then present a case study of the Long-wattled Umbrellabird (Cephalopterus penduliger), where we find support for the hypothesis that off-lek sociality is primarily driven by male reproductive incentives for coordinating lek attendance during the breeding season. During periods of high lekking activity, male umbrellabirds depart the lek in highly coordinated groups and maintain larger off-lek social groups relative to periods of low lekking activity. These seasonal differences in off-lek sociality do not occur in females, are not explained by patterns of foraging behavior, and are expected to confer individual-level benefits for participating males. Both the literature review and empirical study of umbrellabirds suggest that off-lek interactions and behavioral strategies may shape sexual selection processes at leks in important ways. Further research into this historically understudied area of lekking species' behavioral ecology will likely deepen our understanding of the evolutionary dynamics of lek mating. Social behavior away from the lek may influence and interact with sexual selection processes in important ways, yet this component of lekking species' behavioral ecology remains very poorly known. A synthetic literature review suggests considerable diversity in the form and degree of off-lek sociality among lekking birds, both within and between species. Potential adaptive explanations for the function of off-lek sociality in a given species include foraging enhancement, predation avoidance, and mating benefits. In Long-wattled Umbrellabirds, we find that the size and coordination of male off-lek groups increases during the mating season. This pattern is not observed in females and is not related to the proportion of fruit in the diet. We suggest that off-lek sociality in umbrellabirds enables males to synchronize foraging and display periods, which is expected to confer individual-level reproductive benefits. Evidencia anecdótica sugiere que las aves que forman leks exhiben variación considerable en la forma y el grado de sociabilidad fuera del lek, pero este fenómeno ha recibido poca atención teórica o empírica. Aquí, presentamos la primera revisión sintetizada de la literatura sobre la sociabilidad fuera del lek en aves y desarrollamos una estructura conceptual para la función adaptativa potencial de la sociabilidad fuera del lek en taxones que forman leks. Luego, presentamos un estudio de caso del Pájaro Paraguas Longipéndulo (Cephalopterus penduliger), en donde encontramos sustento para la hipótesis que la sociabilidad fuera del lek es impulsada principalmente por incentivos reproductivos de los machos para coordinar la asistencia al lek durante la temporada de reproducción. Durante períodos de alta actividad en los leks, los machos se alejan del lek en grupos altamente coordinados y mantienen grupos sociales más grandes fuera del lek en relación con los períodos de baja actividad en los leks. Estas diferencias estacionales en la sociabilidad fuera del lek no ocurren en las hembras, no se explican por patrones de comportamiento de forrajeo, y se espera que otorguen beneficios a nivel individual para los machos participantes. Tanto la revisión de la literatura como los estudios empíricos del Pájaro Paraguas Longipéndulo sugieren que las interacciones fuera del lek y las estrategias de comportamiento pueden influir de manera importante en los procesos de selección sexual en los leks. Investigaciones adicionales en esta área históricamente poco estudiada de la ecología del comportamiento de las especies que forman leks probablemente profundizarán nuestra compresión de las dinámicas evolutivas de los sistemas de apareamiento en lek.
Counts of males displaying on breeding grounds are the primary management tool used to assess population trends in lekking grouse species. Despite the importance of male lek attendance (i.e., ...proportion of males on leks available for detection) influencing lek counts, patterns of within season and between season variability in attendance rates are not well understood. We used high‐frequency global positioning system (GPS) telemetry data from male greater sage‐grouse (Centrocercus urophasianus; n = 67) over five lekking seasons (2013–2017) at eight study sites in Nevada to estimate lek attendance rates. Specifically, we recorded daily locations of sage‐grouse in relation to mapped lek boundaries and used generalized additive models to assess temporal variation in attendance rates by age class (subadult vs. adult). Average timing of peak attendance occurred on 16 April but varied from March 16, 2014 to April 21 , 2016. Overall, adult males attended leks at higher rates (0.683 at peak) and earlier in the season (19 March) than subadults (0.421 at peak on April 19). Peak attendance probability was positively related to cumulative winter precipitation. Daily probabilities of lek switching differed between adults (0.019 at peak on March 3) and subadults (0.046 at peak on March 22), and lek switching was negatively related to distance to nearest lek. Our results indicate variable patterns in lek attendance through time, and that lek switching may occur at higher rates than previously thought. We demonstrate the use of generalizable daily attendance curves to date‐correct lek counts and derive estimates of male abundance, although such an approach will likely require the incorporation of information on age structure to produce robust results that are useful for population monitoring.
Med gjeninnføring av lek i skolens læreplan er det behov for å vurdere hvordan lek har vært knyttet til matematikk i barnehagen. Vi bruker en modell som kobler sammen barns lek med det å stille og å ...løse problemer, til å analysere barnehagebarns engasjement med digitale apper og til andreklassingers skriving av regnefortellinger. Analysen viser hvordan lek kan oppstå når barna stiller problemer, og når de prøver ut ulike løsningsstrategier. Vi anser at resultatet av forskningen kan gi innsikt til matematikklærere i de første skoleårene om lekens potensial i arbeid med problemstilling og problemløsning. English abstract Play with problems With the reintroduction of play in the school’s curriculum, there is a need to assess how play has been linked to mathematics in kindergarten. We use a model that connects children’s play with posing and solving problems to analyse kindergarten children’s involvement with digital apps and 2nd grade students’ writing of regnefortellinger or number stories. The analysis shows how play can occur when the children pose problems and when they try out different solution strategies. We believe that the results of the research can provide insight to mathematics teachers in the first years of school about the potential for play in problem posing and problem solving.
ABSTRACT
Humpback whales (Megaptera novaeangliae) are seasonal breeders, annually migrating from high‐latitude summer feeding grounds to low‐latitude winter breeding grounds. The social matrix on the ...winter grounds is a loose network of interacting individuals and groups and notably includes lone males that produce long bouts of complex song that collectively yield an asynchronous chorus. Occasionally, a male will sing while accompanying other whales. Despite a wealth of knowledge about the social matrix, the full characterization of the mating system remains unresolved, without any firm consensus, as does the function of song within that system. Here, I consider and critically analyse three proposed functions of song that have received the most attention in the literature: female attraction to individual singers, determining or facilitating male–male interactions, and attracting females to a male aggregation within the context of a lekking system. Female attraction suggests that humpback song is an advertisement and invitation to females, but field observations and song playback studies reveal that female visits to individual singers are virtually absent. Other observations suggest instead that females might convey their presence to singers (or to other males) through the percussive sounds of flipper or tail slapping or possibly through vocalizations. There is some evidence for male–male interactions, both dominance and affiliative: visits to singers are almost always other lone males not singing at that time. The joiner may be seeking a coalition with the singer to engage cooperatively in attempts to obtain females, or may be seeking to disrupt the song or to affirm his dominance. Some observations support one or the other intent. However, other observations, in part based on the brevity of most pairings, suggest that the joiner is prospecting, seeking to determine whether the singer is accompanying a female, and if not soon departs. In the lekking hypothesis, the aggregation of vocalizing males on a winter ground and the visits there by non‐maternal females apparently for mating meet the fundamental definition of a lekking system and its role though communal display in attracting females to the aggregation, although not to an individual singer. Communal singing is viewed as a form of by‐product mutualism in which individuals benefit one another as incidental consequences of their own selfish actions. Possibly, communal singing may also act to stimulate female receptivity. Thus, there are both limitations and merit in all three proposals. Full consideration of song as serving multiple functions is therefore necessary to understand its role in the mating system and the forces acting on the evolution of song. I suggest that song may be the prime vector recruiting colonists to new winter grounds pioneered by vagrant males as population pressures increase or as former winter grounds become unavailable or undesirable, with such instances documented relatively recently. Speculatively, song may have evolved historically as an aggregating call during the dynamic ocean conditions and resulting habitat uncertainties in the late Miocene–early Pliocene epochs when Megaptera began to proliferate. Early song may have been comprised of simpler precursor sounds that through natural selection and ritualization evolved into complex song.
Lek har fra Normalplan 1922 vært omtalt som en del av kroppsøvingsfaget i skolen, og som del av fornyelsen av faget i Kunnskapsløftet 2020 (LK20) skal lek vektlegges i større grad enn tidligere. Det ...finnes lite forskning om hvordan læreplanene omtaler lek og lekens plass i kroppsøvingsundervisningen. I det store tilfanget av lekteori ser det ut til å være enighet om noen kjennetegn ved leken, men det er til dels sterk uenighet om andre. Artikkelen undersøker på denne bakgrunn følgende problemstilling: Hvordan er lek konseptualisert i norske læreplaner i kroppsøving fra 1922 til og med Kunnskapsløftet 2020 (LK20)? Dette gjøres gjennom analyse av i hvilke kombinasjoner begrepet lek er brukt i de ulike læreplanene, og hvilke forventinger som skapes til lek, gjennom lekens retoriske funksjon. Med utgangspunkt i historisk konseptualisering Koselleck (1985) gjennomføres en nærlesning og analyse av læreplanene basert på «conceptually oriented criticism» (Jasinski, 2001a; 2001b). Resultatene viser at læreplanene skaper forventninger om at lek skal gi ulike typer bidrag i kroppsøving og at de ulike forventningene kan stå i ulike relasjoner til annet innhold og metoder i faget. Dette kan også forstås som et uttrykk for asymmetri. Selv om lek gjerne omtales som å ha egenverdi, er det i et historisk perspektiv de instrumentelle forventningene til lek som i størst grad blir retorisk synlig i læreplanene. Vi mener det er et behov for å diskutere lekbegrepet i kroppsøving og hva lek skal bidra med i faget. Videre er det også behov for mer forskning om hva som foregår i kroppsøving når lek er en del av undervisningen.
Lek har fra Normalplan 1922 vært omtalt som en del av kroppsøvingsfaget i skolen, og som del av fornyelsen av faget i Kunnskapsløftet 2020 (LK20) skal lek vektlegges i større grad enn tidligere. Det ...finnes lite forskning om hvordan læreplanene omtaler lek og lekens plass i kroppsøvingsundervisningen. I det store tilfanget av lekteori ser det ut til å være enighet om noen kjennetegn ved leken, men det er til dels sterk uenighet om andre. Artikkelen undersøker på denne bakgrunn følgende problemstilling: Hvordan er lek konseptualisert i norske læreplaner i kroppsøving fra 1922 til og med Kunnskapsløftet 2020 (LK20)? Dette gjøres gjennom analyse av i hvilke kombinasjoner begrepet lek er brukt i de ulike læreplanene, og hvilke forventinger som skapes til lek, gjennom lekens retoriske funksjon. Med utgangspunkt i historisk konseptualisering Koselleck (1985) gjennomføres en nærlesning og analyse av læreplanene basert på «conceptually oriented criticism» (Jasinski, 2001a; 2001b). Resultatene viser at læreplanene skaper forventninger om at lek skal gi ulike typer bidrag i kroppsøving og at de ulike forventningene kan stå i ulike relasjoner til annet innhold og metoder i faget. Dette kan også forstås som et uttrykk for asymmetri. Selv om lek gjerne omtales som å ha egenverdi, er det i et historisk perspektiv de instrumentelle forventningene til lek som i størst grad blir retorisk synlig i læreplanene. Vi mener det er et behov for å diskutere lekbegrepet i kroppsøving og hva lek skal bidra med i faget. Videre er det også behov for mer forskning om hva som foregår i kroppsøving når lek er en del av undervisningen.
The Pha Lek Fe-polymetallic deposit in the southwest of the Truong Son orogenic belt records the evolution and metallogenesis of the southeastern Asia Tethys. Debates remain on the roles the Late ...Triassic volcanism played in the formation of the iron oxides of the deposit. Petrographic and SEM studies led to the recognition of two dominant iron oxides (magnetite and hematite) and three stages of mineralization (pre-ore, syn-ore, and post-ore stages). In situ LA–ICP–MS analyses for trace elements and Fe and O isotopic analyses were applied to understand the origin of the iron oxides. Generally, iron oxide of the syn-ore stage has higher total trace elements than post-ore stage, and magnetite has higher lithophile elements, whereas hematite has higher chalocophile elements. The trace-element abundance in magnetite is most comparable to porphyry-skarn-hydrothermal magnetite, and hematite is more comparable to supergene and secondary, non-magmatic hydrothermal chemistry. All δ
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Fe values of the iron-oxide separates are above 0‰ and have an igneous signature, and syn-ore stage magnetite has relatively higher δ
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Fe values than the post-ore stage hematite. All δ
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O values of the iron-oxide separates are below 1‰ and plot within the non-igneous field, and show a similar decreasing trend from syn-ore stage magnetite to post-ore stage hematite. We propose that the Triassic volcanic activities played a limited role during the mineralization process; the deposit was formed because of the Late Carboniferous–Early Permian, porphyry-skarn-related, magmatic hydrothermal alteration; and the mixing of non-magmatic fluid and/or the supergene weathering caused the wide reprecipitation of Fe oxides. An evolutionary mineralization model related to the low-angle subduction for the deposit is also proposed.
Läroplanens krav på att förskolans innehåll och arbetssätt skall vila på vetenskaplig grund och beprövad erfarenhet innebär att förskolans didaktiska verktyg behöver få stöd av forskning. Då lek har ...en central plats i förskolan kan en utveckling av ett lekfullt verktyg som dockor vara motiverat. Därför syftar denna studie till att studera hur forskning behandlar möjligheter och utmaningar med dockor som didaktiskt verktyg i förskolan. En systematisk granskning har genomförts av 29 vetenskapliga artiklar. Fyra områden med möjligheter för dockor som didaktiskt verktyg identifieras, förskolebarns sociala kompetens, kommunikation, ämneslärande och barns lek. Vidare framkom två områden med utmaningar, pedagogiska och kontextuella, relaterat till dockor som didaktiskt verktyg. Diskussionen berör både möjligheterna och utmaningarna med dockor som didaktiskt verktyg. Dockor konstateras ha en potential som didaktiskt verktyg i förskolan.
Det har skjedd store endringer i barnehagesektoren i Norge de siste årene. Barnehagen har blitt et sentralt utdanningspolitisk satsingsområde, de største private barnehagekjedenes eierandel har økt ...vesentlig og barnehagepedagogikken er blitt et attraktivt marked for produsenter av standardiserte programmer og manualer. I denne artikkelen diskuteres ulike ideer om utdanning og vilkårene for barns rettigheter basert på tekstanalyse av 100 årsplaner for barnehager. Det er gjort en kvantitativ innholdsanalyse for å kartlegge forekomsten av ord og begreper innenfor kategoriene deltakelse, utdanning, omsorg og lek, hvile og fritid. Videre er et utvalg av 25 årsplaner analysert kvalitativt. Et av hovedfunnene er at større barnehager drevet som aksjeselskap, barnehager som kjøper programmer utenfra og barnehager tilknyttet Agderprosjektet, har en tendens til å vektlegge utdanning og læring i større grad enn omsorg, hvile og lek. Artikkelen avsluttes med en drøfting av mulige drivkrefter som kan ha innvirkning på barnehagepedagogikken.
The stalked barnacle Pollicipes pollicipes is an important economic resource in Portugal and Spain. Two extreme phenotypes can be identified, based on their morphology. More elongated barnacles are ...associated with bad quality and have a lower commercial value.
The fishers perception about the existence, definition and causes for this phenotypical/quality variation was evaluated through a survey performed in Portugal and Galicia, Spain. The existence of two extreme commercial qualities was validated. Good quality barnacles were mainly defined as thick and short in both countries. In Spain (Galicia), the definition of bad quality animals corresponded mainly to the terms long and thin, while in Portugal, fishers used a wider variety of terms including watery, thin and soft. The characteristics of the rock and the hydrodynamics were the causes most referred by the fishers for this variation.
The morphological variation of P. pollicipes was described by the ratio between maximal rostro-carinal length (RC) and total height (TH): RC/TH values > 0.4 indicate good quality barnacles; and values < 0.4 indicate bad quality barnacles.
Although morphological variation between the two extreme qualities/phenotypes was found, no genetic (amplified fragment length polymorphism - AFLP) or epigenetic (methylation sensitive amplification polymorphism - MSAP) differences were detected.
•Fishers confirmed the existence of two commercial qualities of Pollicipes pollicipes.•Good quality barnacles were defined by fishers as being thick and short.•Bad quality barnacles definition included the terms long, thin, watery, and soft.•RC/TH ratio can describe the morphological variation between the extreme phenotypes•No genetic or epigenetic differences were detected between both qualities/phenotypes.
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