Association patterns in three populations of Hector's dolphin, Cephalorhynchus hectori

1999 ◽  
Vol 77 (1) ◽  
pp. 13-18 ◽  
Author(s):  
Stefan Bräger

Most delphinids are very social and spend much time in the presence of conspecifics. The proportion of co-occurrences of any two individuals is usually measured by means of association indices. In this study, the "half-weight index" was used to describe the association patterns in three previously unstudied populations of Hector's dolphin, Cephalorhynchus hectori, around the South Island of New Zealand. For inclusion in this analysis individuals were photoidentified repeatedly over a 2-year study period. Only about 1% of the individual associations of dolphin pairs (dyads) tested were found to be significantly different (p less than or equal to 0.01) from random distributions derived from a new constrained Monte Carlo randomisation. The overall association patterns in the two study populations off Kaikoura ( n = 48 individuals) and Moeraki (n = 24) did not differ significantly from what could be expected by chance (p = 0.07 and 0.09, respectively), whereas those in the Jackson Bay population (n = 38) were significantly different from chance (p < 0.0002). Hector's dolphins appear to have a typical fission-fusion society, with many weak associations within the wider envelope of the local population.

Author(s):  
E.Bruce Levy

THE ultimate structure in vegetation is determined by dominance, and dominance is based on the ability of the individual to respond to its environment. No two plants arc exactly alike in their demands : each plant has its special growing-place. The indigenous forests in general carry a single dominant that largely determines the physiognomic features of the formation-the tawa or rimu, or white pine, or kauri, or totara, or southern beech. In forest development we recognize succession, and dominants appear to mark each phase in the .succession : thus we have the manuka dominance, bracken fern,. the indigenous induced hard fern, piripiri dominance, wineberry, mahoe, five-finger dominance, progressing to rewarewa, hinau, or kamahi dominance. In the tussock grasslands we see the same rise to dominance according to growing-place- the fescue tussock, the poa . tussock, the danthonia tussock ; and in the depleted lands of the South Island we see the scabweed dominant under the influence of the rabbit. In the artificial grasslands of New Zealand the trend to dominance is well observed - the rye-grass, cocksfoot, brown-top, Danthonia eilosa, .D. semiannzclaris, ratstail, paspalum, tall fescue, prairie-grass, floating sweetgrass, and Poa aquatica dommance respectively.


Author(s):  
Eva-Marie Kröller

This chapter discusses national literary histories in Australia, Canada, New Zealand, and the South Pacific and summarises the book's main findings regarding the construction and revision of narratives of national identity since 1950. In colonial and postcolonial cultures, literary history is often based on a paradox that says much about their evolving sense of collective identity, but perhaps even more about the strains within it. The chapter considers the complications typical of postcolonial literary history by focusing on the conflict between collective celebration and its refutation. It examines three issues relating to the histories of English-language fiction in Australia, Canada, New Zealand, and the South Pacific: problems of chronology and beginnings, with a special emphasis on Indigenous peoples; the role of the cultural elite and the history wars in the Australian context; and the influence of postcolonial networks on historical methodology.


2020 ◽  
Vol 26 (3) ◽  
pp. 223-244
Author(s):  
W. John Thrasher ◽  
Michael Mascagni

AbstractIt has been shown that when using a Monte Carlo algorithm to estimate the electrostatic free energy of a biomolecule in a solution, individual random walks can become entrapped in the geometry. We examine a proposed solution, using a sharp restart during the Walk-on-Subdomains step, in more detail. We show that the point at which this solution introduces significant bias is related to properties intrinsic to the molecule being examined. We also examine two potential methods of generating a sharp restart point and show that they both cause no significant bias in the examined molecules and increase the stability of the run times of the individual walks.


Author(s):  
Su Yeon Roh ◽  
Ik Young Chang

To date, the majority of research on migrant identity negotiation and adjustment has primarily focused on adults. However, identity- and adjustment-related issues linked with global migration are not only related to those who have recently arrived, but are also relevant for their subsequent descendants. Consequently, there is increasing recognition by that as a particular group, the “1.5 generation” who were born in their home country but came to new countries in early childhood and were educated there. This research, therefore, investigates 1.5 generation South Koreans’ adjustment and identity status in New Zealand. More specifically, this study explores two vital social spaces—family and school—which play a pivotal role in modulating 1.5 generation’s identity and adjustment in New Zealand. Drawing upon in-depth interviewing with twenty-five 1.5 generation Korean-New Zealanders, this paper reveals that there are two different experiences at home and school; (1) the family is argued to serve as a key space where the South Korean 1.5 generation confirms and retains their ethnic identity through experiences and embodiments of South Korean traditional values, but (2) school is almost the only space where the South Korean 1.5 generation in New Zealand can acquire the cultural tools of mainstream society through interaction with English speaking local peers and adults. Within this space, the South Korean 1.5 generation experiences the transformation of an ethnic sense of identity which is strongly constructed at home via the family. Overall, the paper discusses that 1.5 generation South Koreans experience a complex and contradictory process in negotiating their identity and adjusting into New Zealand through different involvement at home and school.


1929 ◽  
Vol 19 (1) ◽  
pp. 67-87 ◽  
Author(s):  
Jocelyn Toynbee

The paintings in the triclinium of the Villa Item, a dwelling-house excavated in 1909 outside the Porta Ercolanese at Pompeii, have not only often been published and discussed by foreign scholars, but they have also formed the subject of an important paper in this Journal. The artistic qualities of the paintings have been ably set forth: it has been established beyond all doubt that the subject they depict is some form of Dionysiac initiation: and, of the detailed interpretations of the first seven of the individual scenes, those originally put forward by de Petra and accepted, modified or developed by Mrs. Tillyard appear, so far as they go, to be unquestionably on the right lines. A fresh study of the Villa Item frescoes would seem, however, to be justified by the fact that the majority of previous writers have confined their attention almost entirely to the first seven scenes—the three to the east of the entrance on the north wall (fig. 3), the three on the east wall and the one to the east of the window on the south wall, to which the last figure on the east wall, the winged figure with the whip, undoubtedly belongs.


During the latter part of 1902 and the early months of 1903 I resolved to take as many observations of the rates of dissipation of positive and negative electric charges as possible, and to continue them over the whole 24 hours of the day, and, when opportunity offered, over longer periods. There appeared to be little information regarding the rate of dispersion during the night hours. At about the same time that these observations were being made, Nilsson was doing similar work at Upsala, and found a noticeable maximum value for atmospheric conductivity at about midnight. The observations were made on the Canterbury Plains of New Zealand, at a station about 20 feet above sea-level and about five miles due west from the sea coast. The apparatus used was Elster and Geitel’s Zerstreuungs- apparat , and the formula of reduction used was that given by them, viz:- E = 1/ t log V 0 /V- n / t ' log V' 0 /V' . In this formula E is proportional to the conductivity of the gas surrounding the instrument—for positive or negative charges, as the case may be. The constant “ n ” = ratio of capacity without cylinder ____________________________________ capacity with cylinder was determined by me to be 0·47, as the instrument was always used, with the protecting cover. The cover was always at one height above the base of the instrument, and was set so as to be as nearly co-axial with the discharging cylinder as could be judged by eye. No attempt was made to determine the actual capacity of the condenser cylinder and protecting cover, which would be a somewhat variable quantity owing- (1) to the differences on different days in attempting to cause the two to be co-axial; (2) to a certain amount of looseness in the fit of the shank of the cylinder on to its hole. The value above given for “ n "is the mean of several deter­minations made with different settings of the cover and cylinder. The individual values of “ n ” varied over about 0.03.


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