14 resultados para Indo-west Pacific

em Deakin Research Online - Australia


Relevância:

100.00% 100.00%

Publicador:

Resumo:

The abundant fossil record of well-preserved Bryozoa in samples from the Tertiary of Victoria and South Australia includes some 'first fossil finds' which are recorded here. Several are of species known from the Recent of the Australian or Indo-West-Pacific regions, but some represent genera with a much wider temporal and geographical range. Of the 11 species illustrated, six are known, or may be inferred, to have inhabited 'sand fauna' environments. Specimens of one species are complete enough to allow its formal description as Chlidoniopsis inopina sp. nov.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The genus Adeona is a characteristic and common part of the Australian shelf fauna, extending to the tropical Indo-West Pacific. The genus first appears in the fossil record of the Miocene of south-eastern Australia. Zooid dimorphism has been recognised initially from subtle differences in the external appearance, which have not been described previously. Detailed examination has shown enlarged brooding zooids with marked differences from autozooids in the internal structure of the peristomes and in the occurrence of a primary calcified orifice.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

However derived, predictions of global marine species diversity rely on existing real data. All methods, whether based on past rates of species descriptions, on expert opinion, on the fraction of undescribed species in samples collected, or on ratios between taxa in the taxonomic hierarchy, suffer the same limitation. Here we show that infaunal macrofauna (crustaceans and polychaetes) of the lower bathyal depth range are underrepresented among available data and documented results from Australia. The crustacean and polychaete fauna (only partially identified) of the bathyal continental margin of Western Australia comprised 805 species, representing a largely novel and endemic fauna. Overall, 94.6% of crustacean species were undescribed, while 72% of polychaete species were new to the Australian fauna, including all tanaidaceans, amphipods, and cumaceans, as well as most isopods. Most species were rare, and the species accumulation rate showed no sign of reaching an asymptote with increasing area sampled. Similar data are likely for the largely unexplored bathyal regions. This leads us to conclude that the numbers upon which extrapolations to larger areas are based are too low to provide confidence. The Southern Australian and Indo-West Pacific deep-sea regions contribute significantly to global species diversity. These regions and bathyal and abyssal habitats generally are extensive, but are so-far poorly sampled. They appear to be dominated by taxonomically poorly worked and species-rich taxa with limited distributions. The combination of high species richness among infaunal taxa-compared to better known taxa with larger individuals, higher endemism than presently acknowledged because of the presence of cryptic species, the low proportion of described species in these taxa, and the vast extent of unexplored bathyal and abyssal environments-will lead to further accumulation of new species as more and more deep sea regions are explored. It remains to be tested whether ratios of 10 or more undescribed to described species, found in this study for the dominant taxa and for the deep Southern Ocean and the Indo-West Pacific, are replicable in other areas. Our data and similar figures from other remote regions, and the lack of faunal overlap, suggest that Appeltans et al.'s (Current Biology 22:1-14, 2012) estimate that between one-third and two-thirds of the world's marine fauna is undescribed is low, and that Mora et al.'s (PLoS Biol 9(8):e1001127. doi:10.1371/journal.pbio.1001127, 2011) of 91% is more probable. We conclude that estimates of global species, however made, are based on limited data. © 2014 Senckenberg Gesellschaft für Naturforschung and Springer-Verlag Berlin Heidelberg.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

Twenty-one molecular genetic studies of thirteen antitropical Pacific fishes are herein reviewed. High dispersal potentials and Plio-Pleistocene transequatorial divergence are suggested for approximately half of the taxa studied, consistent with movement across the tropics during glacial periods. Divergences within two fish groups were mid-Miocene in age, corresponding to a period suggested for vicariant isolation associated with equatorial warming, but high dispersal potentials complicate the interpretation of biogeographic history. Only one study suggested transequatorial divergence older than 20 million years. There is a greater proportion of Pleistocene transequatorial divergences in the East Pacific than the West Pacific, consistent with the suggestion that conditions in the East Pacific are more amenable to the formation of antitropical distributions. Multiple transequatorial divergences have been observed within at least two groups, and instances of cryptic speciation have been identified twice. Areas for future research concern taxa that differ from the majority studied to date with respect to latitudinal distribution, bathymetry, evolutionary age, and dispersal potential. Molecular characters have demonstrated utility for the study of antitropical fishes, but with limitations.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Three closely allied shallow marine taxa, Neohornibrookella sorrentae (Chapman and Crespin), Neohornibrookella glyphica (Neil), and Neohornibrookella nepeani sp. nov. are recorded from latest early Miocene to late Pliocene strata in southeastern Australia. These taxa, together with Neohornibrookella quadranodosa (Holden) from the Miocene of Midway Island (Northwestern Hawaiian Islands), form a morphologically distinct group of relatively large species (the sorrentae-group) within the genus Neohornibrookella Jellinek. Latitudinal expansion of the subtropical and warm-temperate climatic belts together with the influence of warm western boundary surface currents associated with the North and South Pacific gyres, are likely to have played key roles in the Miocene dispersal of this species group. Species of the sorrentae-group first migrated south from equatorial west Pacific regions into southeastern Australia during the early Miocene, under the influence of the East Australian Current. During three time intervals (i) latest early Miocene, (ii) latest late Miocene and (iii) earliest late Pliocene, forceful pulses of the East Australian Current played a significant role in propelling the widespread distribution of thermophilic Neohornibrookella species across southeast Australian shallow marine realms. During intervening middle and late Miocene times, Neohornibrookella species are only sporadically present across the Bass Strait region of southeast Australia, indicating a weaker East Australian Current influence and the cooling influence of coastal upwelling. During the mid early Pliocene Neohornibrookella species disappeared from the western Bass Strait region, suggesting the complete exclusion of East Australian Current waters from this region. This was probably due to the counteracting influence of the eastward flowing Zeehan Current (extension of the Leeuwin Current) impinging on the western Bass Strait region. This mid early Pliocene palaeobiogeographical partition in Bass Strait, defined by the distribution of sorrentae-group species, is here termed the Bassian Gateway. The two species, N. sorrentae and N. glyphica, occur concurrently during the mid Miocene in southeast Australia, but are associated with different lithofacies. It is hypothesised that there is a heterochronic evolutionary relationship expressed in the ornament of these two species. The thaerocytherid genera Neohornibrookella Jellinek, Tenedocythere Sissingh and Bosasella Bonaduce are here included in the new ostracod subfamily Tenedocytherinae.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Concepts about space and time, such as the Asia-Pacific and the Asian Century, are not articulated lightly in international relations discourses. When a spatial or temporal term comes into vogue, it often comes with political connotations and policy implications. This is the context in which we ought to consider the making of the spatial term Indo-Pacific, which has recently made it into the lexicon of official speeches, think-tank reports, government white papers and scholarly works. While many pundits and practitioners are embracing this new formulation, others cast doubt on its usefulness or even question its actual existence. Yet, despite its sudden stardom in foreign policy circles and some debate around its policy implications, how the Indo-Pacific as a political spatial concept came about has not been well understood.To address this gap, this chapter will first briefly survey the Indo-Pacific debate and examine how the debate has not paid adequate attention to the issue of the Indo-Pacific as a discursive construct. It then turns to how the United States, Australia, Japan, India and China together contribute to the formation of this concept amid ongoing geopolitical anxieties about the shape and trajectory of future Asian regional order. While acknowledging China's role in this constitutive process, I argue that as a discursive construct the Indo-Pacific has been motivated primarily by geopolitical anxieties about a perceived emerging regional order dominated by China. Driven by such anxieties, the concept is not an innocent description of a natural region out there; it has the potential of fuelling regional rivalries and exacerbating security dilemmas. Given its possible destabilising consequences, the chapter concludes with a call for a critical reimagination of this now increasingly accepted term.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Explanations of the origin and genesis of Pacific field monuments commonly assume they reflect local social change in islands or island groups which were increasingly isolated following colonization. A recent review of early West Polynesian archaeology suggests that the penecontemporaneous appearance of various kinds of field monuments from eastern Melanesia to Polynesia may be better explained as evidence of interaction and the movement of people and/or ideas, possibly associated with the colonization of East Polynesia.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Strategic ties based on converging national interests shared perceptions of the evolving Asia-Pacific security environment are strengthening between India and USA. The sanctions imposed in response to IndiaEs 1998 nuclear tests were relaxed and military-to-military links were stored with the joining of India in US-led war on terror.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Development in Papua New Guinea ... is research into village level issues of logging. In New Britain, nationals are offered royalties for cutting their rainforest. Information about ecology and biodiversity is usually late in coming, and such information to them does not appear to advance their development. This thesis offers the most specific method for dealing with small communities in Papua New Guinea, and confronts the issue of self development. It is posited that all other development must encourage self development in Papua New Guinea. Evidence brought here shows the need to make the Melanesian community central to development strategies.

To accomplish such a strategy, there is a need to consider Melanesian cultures. An explanation of world views ensues. The world views of people of the Pasismanua region, of New Britain's south coast, was compared broadly with Melanesian cultures and Melanesian development in a variety of circumstances. Consequently, the suggestions made are broadly applicable to situations where resources must be well monitored. There are many such situations in Pacific nations, which suggests that the thesis will be of usc to a wide research community.

Since research is grounded in ethnographic as well as other research, this kind of study generates many other research questions, and the research is designed to lead to other studies. Certain aspects of the design become disclosed when the research has progressed. As well, the background of an expatriate researcher is intrusive, and must be mitigated by some form of participation in the host culture. This is a central tenet of the thesis. This participation increases sensitivity to culture and yields a circumspect consideration of the colonial issue. Occupied for many years by colonial powers especially Australia, all New Guinea including West New Britain shows the effects of colonisation. It also shows evidence of the new colonialism of cash-cropping, and of the destruction of biodiversity. This becomes a central theme, as does the position of this researcher as a participant in a global economic culture encroaching on and invited by Papua New Guinea.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

 This paper examines assumptions about democracy and the role of media held by journalism educators working outside Australia, and the extent to which those assumptions influence teaching styles, regardless of the maturity of the political systems in the nations in question. This paper looks at the work emerging from academics Beate Josephi, Barbie Zelizer, John Nerone, Cherian George and Silvio Waisbord, who argue in Journalism (2012) that there needs to be a change to the understanding by journalism scholars of the central place of journalism in democracy because that view is not global in its perspective. This paper specifically considers Zelizer’s point that “much of the scholarly world in the West – and specifically in the United States – depends directly or indirectly on the presumption of democracy and its accoutrements”. The researcher asks, “what can we learn about our Australian perspective on teaching journalism in the developing world where there may not, yet, be an operating democracy or a form of democracy that replicates the Western liberal model?”