695 research outputs found
An Archaeological Site on Karluk Island in Crozier Strait, N.W.T.
During a marine geophysical exploration, in 1973, of the proposed route of a gas pipeline across Crozier Strait (between Bathurst Island and Little Cornwallis Island) in the Canadian Arctic Archipelago, the present author landed on the western side of Karluk Island, which is situated in the narrowest part of the Strait. There, conspicuous on a small point facing south and west, and directly west of a small lake, he noticed a newly-erected small cairn of a lead-zinc claim which led him inadvertently to the discovery of an archaeological site. Three or four depressions, each not more than 30 cm deep and filled with a thick, spongy, brilliant green moss, stood out in contrast to the surrounding brown rock rubble. ..
Effects of Prescribed Burns on Grassland Breeding Birds at Mississippi Sandhill Crane National Wildlife Refuge
There has been a critical decline in grassland bird populations due to habitat fragmentation and deterioration, and suppression of natural fires. Alteration of the disturbance cycle may lead to changes in vegetation structure and thus habitat suitability for breeding grassland birds. Management practices at the Mississippi Sandhill Crane National Wildlife Refuge, including the use of prescribed fire, are in need of evaluation. My study asked what frequency of prescribed burns is necessary to support breeding grassland birds and whether vegetation structure varies among burn units. In this study, bird abundance and species richness did not differ significantly among burn units and vegetation cover-type was not a strong predictor of these factors either. There was evidence of site utilization by breeding grassland birds immediately following a burn, which suggests that the bird community is able to recovery quickly post-fire and these units may serve as viable habitat for breeding grassland birds
Children's working understanding of knowledge sources : confidence in knowledge gained from testimony
In three experiments children aged between 3 and 5 years (N = 38; 52; 94; mean ages 3;7 to 5;2) indicated their confidence in their knowledge of the identity of a hidden toy. With the exception of some 3-year-olds, children revealed working understanding of their knowledge source by showing high confidence when they had seen or felt the toy, and lower confidence when they had been told its identity by an apparently well-informed speaker, especially when the speaker subsequently doubted the adequacy of his access to the toy. After a 2-minute delay, 3-to 4- year olds, unlike
4- to 5-year-olds, failed to see the implications of the speakerâs doubt about his access
Minding the children: a longitudinal study of mental state talk, theory of mind and behavioural adjustment from age 3 to age 10
Mothersâ use of mental state talk (MST) is linked to young childrenâs performance on false belief tests of theory of mind (ToM) and to their behaviour in social contexts. However, little is known about MST beyond the early years. This investigation is the first to examine continuity in both mother and child MST from preschool (age 3â4 years) to middle childhood (age 10) and examines the role of early maternal MST in childrenâs later ToM and use of MST. We examine the novel association between MST and childrenâs behavioural adjustment from preâschool into late childhood. Participants were motherâchild dyads from a 7âyear longitudinal study. Measures of MST, ToM, and language were administered at home when children were 3 and 4 years old and again at the age of 10. Also at 10, behavioural adjustment was measured using the Strengths and Difficulties Questionnaire. Mother and child MST were highly stable from preschool to later childhood. Early maternal MST accounted for unique variance in later child MST and behavioural adjustment at 10 years of age; children whose mothers used more MST, specifically references to cognitions, when they were 3 or 4 experienced fewer behavioural difficulties (externalising behaviour) when they were 10 years old
Children's suggestibility in relation to their understanding about sources of knowledge
In the experiments reported here, children chose either to maintain their initial belief about an object's identity or to accept the experimenter's contradicting suggestion. Both 3â to 4âyearâolds and 4â to 5âyearâolds were good at accepting the suggestion only when the experimenter was better informed than they were (implicit source monitoring). They were less accurate at recalling both their own and the experimenter's information access (explicit recall of experience), though they performed well above chance. Children were least accurate at reporting whether their final belief was based on what they were told or on what they experienced directly (explicit source monitoring). Contrasting results emerged when children decided between contradictory suggestions from two differentially informed adults: Threeâ to 4âyearâolds were more accurate at reporting the knowledge source of the adult they believed than at deciding which suggestion was reliable. Decision making in this observation task may require reflective understanding akin to that required for explicit source judgments when the child participates in the task
Mindblind eyes: an absence of spontaneous theory of mind in Asperger syndrome
Adults with Asperger syndrome can understand mental states such as desires and beliefs (mentalizing) when explicitly prompted to do so, despite having impairments in social communication. We directly tested the hypothesis that such individuals nevertheless fail to mentalize spontaneously. To this end, we used an eye-tracking task that has revealed the spontaneous ability to mentalize in typically developing infants. We showed that, like infants, neurotypical adultsâ (n = 17 participants) eye movements anticipated an actorâs behavior on the basis of her false belief. This was not the case for individuals with Asperger syndrome (n = 19). Thus, these individuals do not attribute mental states spontaneously, but they may be able to do so in explicit tasks through compensatory learning
Enigmatic deep-water mounds on the Orphan Knoll, Labrador Sea
Deep-sea mounds can have a variety of origins and may provide hard-substrate features in depths that are normally dominated by mud. Orphan Knoll, a 2 km high bedrock horst off northeast Newfoundland, hosts more than 200 mounds, or mound complexes, of unknown composition, in water depths of 1720â2500 m. Most mounds are 10â600 m high, with average mound height 187 m, and 1â3 km wide. The study objective was to characterize the size, shape, orientation, and composition of the enigmatic Orphan Knoll mounds, in order to determine their age and origin. Archival ship-based side-scan sonar, multibeam sonar, airgun, high-resolution sparker and 3.5 kHz acoustic sub-bottom profiling, and newly acquired ship-based multibeam sonar, video transects by remotely operated vehicle (ROV), rock samples, and near-bottom multibeam sonar data were analyzed. Four mounds were studied during two ROV dives. Archival sidescan sonar data show > 200 mounds. Sparker profiles show that the mound crests are covered by condensed stratified Quaternary sediment and airgun seismic data show faults reaching near the seafloor. New multibeam sonar data show mounds are dominantly conical to elliptical in shape, but without preferred orientation or alignment. Remotely operated vehicle (ROV) transects and near-bottom multibeam showed that three mounds were rounded and symmetrically arranged, while a fourth was more asymmetrical, with steep faces on the southwestern and southeastern flanks, where finely bedded to massive sedimentary bedrock outcropped dipping 15â45°SW. Rock samples from the mounds include Eocene calcareous ooze and mid-Miocene bedded pelagic limestone. Thick ferromanganese crusts were found on many surfaces, obscuring possible outcrops from physical sampling. Polymetallic nodules were found on the slope of one mound. Ice-rafted detritus, including igneous and metamorphic rocks and Paleozoic limestone and dolostone, was common in the sediments immediately surrounding the mounds. Quaternary sub-fossil solitary scleractinian corals accumulated over a span of at least 0.18 Ma at the base of one mound. The presence of uplifted condensed Eocene-Miocene rocks on the mounds and faulting in seismic profiles suggest uplift during reactivation of old rift-related faults during the Neogene, with seabed mass wasting creating residual mounds, which were then draped by Quaternary proglacial muds. Sculpting of hemipelagic Quaternary sediment by bottom currents probably contributed to mound morphology
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