title: Population genetic structures and dispersal patterns of arthropods in New Zealand and the Ross Dependency, Antarctica

authors: Stevens, Mark I.

abstract: Climatic and geological changes have been recognised as fundamental mechanisms in the evolution of populations. This thesis assesses population genetic structures and dispersal patterns of arthropods in two geographic regions-Antarctica and New Zealand-using molecular techniques in conjunction with distributional data and dispersal experiments. 
Regional genetic divergence was revealed using allozymes and mtDNA (COI) for populations of the endemic Antarctic collembolan Gomphiocephalus hodgsoni from southern Victoria Land and Ross Island (Ross Dependency). Genetic discontinuities across geographical barriers (e.g. sea-ice) suggest limited dispersal opportunities and long-term habitat fragmentation throughout the Pleistocene. In addition, the identification of two sympatric and genetically divergent groups throughout one of the continental sites (Taylor Valley) suggests that these mechanisms have been conducive to speciation. The limited mixing of mtDNA haplotypes between one island site (Cape Bird) and one continental site (Granite Harbour) is unlikely to be accounted for by the un-aided dispersal capacity of G. hodgsoni and recent human- or bird-mediated dispersal is highly probable. Furthermore, recent localised dispersal of Collembola was identified in two continental sites (Taylor Valley and Granite Harbour) through comparisons with previous distributional studies, and suggests that range expansion of up to 5 km has occurred within the last 40 years.
The endemic estuarine amphipods Paracorophium lucasi and P. excavatum from North, South and Chatham Islands of New Zealand were examined using allozyme analyses that also identified clear genetic breaks across geographical barriers (e.g. land-bridges) separating biogeographic regions. However, populations of P. lucasi were more divergent than populations of P. excavatum over similar geographic distances, but in most cases gene flow appears to maintain a homogenous population genetic structure in populations that share a common coastline. These results are congruent with a high rate of female-biased juvenile dispersal that was identified during field experiments with Paracorophium spp. in Tauranga Harbour. Such dispersal may be a mechanism to avoid inbreeding and inter- and intraspecific competition. During these experiments, I identified the New Zealand Paracorophium species, as well as P. brisbanensis, previously recorded only from Australia. I conclude that this latter species is unlikely to be indigenous to New Zealand or the result of natural dispersal from Australia, but rather anthropogenic translocation (i.e. shipping activities). 
This research reveals limited dispersal and high levels of genetic divergence for three arthropod taxa from fragmented habitats in Antarctica and New Zealand. I conclude that such levels of cryptic diversity indicate the inadequacies of morphology-based classification schemes. Accordingly, assessments based on genetic diversity (e.g. mtDNA analyses) are required.

text: Population genetic structures and dispersal patterns of arthropods in New Zealand and the Ross Dependency, Antarctica Climatic and geological changes have been recognised as fundamental mechanisms in the evolution of populations. This thesis assesses population genetic structures and dispersal patterns of arthropods in two geographic regions-Antarctica and New Zealand-using molecular techniques in conjunction with distributional data and dispersal experiments. 
Regional genetic divergence was revealed using allozymes and mtDNA (COI) for populations of the endemic Antarctic collembolan Gomphiocephalus hodgsoni from southern Victoria Land and Ross Island (Ross Dependency). Genetic discontinuities across geographical barriers (e.g. sea-ice) suggest limited dispersal opportunities and long-term habitat fragmentation throughout the Pleistocene. In addition, the identification of two sympatric and genetically divergent groups throughout one of the continental sites (Taylor Valley) suggests that these mechanisms have been conducive to speciation. The limited mixing of mtDNA haplotypes between one island site (Cape Bird) and one continental site (Granite Harbour) is unlikely to be accounted for by the un-aided dispersal capacity of G. hodgsoni and recent human- or bird-mediated dispersal is highly probable. Furthermore, recent localised dispersal of Collembola was identified in two continental sites (Taylor Valley and Granite Harbour) through comparisons with previous distributional studies, and suggests that range expansion of up to 5 km has occurred within the last 40 years.
The endemic estuarine amphipods Paracorophium lucasi and P. excavatum from North, South and Chatham Islands of New Zealand were examined using allozyme analyses that also identified clear genetic breaks across geographical barriers (e.g. land-bridges) separating biogeographic regions. However, populations of P. lucasi were more divergent than populations of P. excavatum over similar geographic distances, but in most cases gene flow appears to maintain a homogenous population genetic structure in populations that share a common coastline. These results are congruent with a high rate of female-biased juvenile dispersal that was identified during field experiments with Paracorophium spp. in Tauranga Harbour. Such dispersal may be a mechanism to avoid inbreeding and inter- and intraspecific competition. During these experiments, I identified the New Zealand Paracorophium species, as well as P. brisbanensis, previously recorded only from Australia. I conclude that this latter species is unlikely to be indigenous to New Zealand or the result of natural dispersal from Australia, but rather anthropogenic translocation (i.e. shipping activities). 
This research reveals limited dispersal and high levels of genetic divergence for three arthropod taxa from fragmented habitats in Antarctica and New Zealand. I conclude that such levels of cryptic diversity indicate the inadequacies of morphology-based classification schemes. Accordingly, assessments based on genetic diversity (e.g. mtDNA analyses) are required.

year: 2002

title: Effects of New Zealand general elections on stock market returns

authors: Abidin, Sazali Zainal

subjects: New Zealand

abstract: This paper examines stock returns under both National and Labour governments in New Zealand, offering further insight into the existence of the political cycle effect. Findings indicate the existence of a political cycle effect in stock returns, consistent with a number of recent studies performed within both Australia and New Zealand. New Zealand’s right-of-centre National party are found to be associated with significantly higher stock returns during their terms in office than their left-of-centre counterparts, the Labour party. Our findings add to a growing body of literature, particularly outside of the United States, where investors can expect stock returns to vary depending upon the governing political party and can make better investment decisions accordingly.

text: Effects of New Zealand general elections on stock market returns This paper examines stock returns under both National and Labour governments in New Zealand, offering further insight into the existence of the political cycle effect. Findings indicate the existence of a political cycle effect in stock returns, consistent with a number of recent studies performed within both Australia and New Zealand. New Zealand’s right-of-centre National party are found to be associated with significantly higher stock returns during their terms in office than their left-of-centre counterparts, the Labour party. Our findings add to a growing body of literature, particularly outside of the United States, where investors can expect stock returns to vary depending upon the governing political party and can make better investment decisions accordingly.

year: 2010

title: Māori social identities in New Zealand and Hawai'i

authors: Nikora, Linda Waimarie

subjects: Maori

abstract: This research is comprised of two narrative interview studies of Māori in two different settings, New Zealand (n=20) and Hawai'i (n=30).  The data was gathered over the 1994-1996 period.  The two settings have some commonalities and differences.  In both settings Māori are required to make decisions about the continuity of their ethnic Māori identities and hereditary cultural identities of iwi, hapu and whanau, and the part that they wish these identities to play in their daily lives.  The focus of this research was about how Māori create meaning in their lives and maintain their social identities across and within those contexts they move through. 

The findings of this research suggest that Māori in New Zealand continue to value and gain meaning and satisfaction from their cultural collectivities and the social identities derived from them.  However, the results tend to suggest that there are changes in the ways that individuals conceptualise these identities and concomitantly, how they see of themselves.
For New Zealand participants, conceptions of hapu and iwi appear to be converging with an increasing focus on the physicality of marae, its environment and symbolism, and the social events and relationships negotiated in that space.  New Zealand participants saw some hapu and iwi maintenance activities as more legitimate than others.  More value was placed on returning to hapu and iwi homelands however irregular these returns were.  In contrast, conceptions of hapu and iwi held by participants in Hawai'i seemed less intense.  There were few opportunities to engage with other hapu or iwi members.  Being Māori had greater meaning and was understood, probed and valued by others in the culturally plural context of Hawai'i.  For New Zealand participants, being Māori was enacted in the context of being a discriminated, negatively constructed minority.  All were aware of the defining effect that the presence of a dominant majority could have and countered these effects by engaging in social justice and in-group solidarity activities.

The changing identity conceptions held by members of Māori social groups will have implications for a sense of community and social cohesion, for tribal asset management, service delivery and crown settlement processes.  If Māori are redefining and renegotiating their social identities to achieve greater meaning and satisfaction then these changes are important to respond to and recognise.

text: Māori social identities in New Zealand and Hawai'i This research is comprised of two narrative interview studies of Māori in two different settings, New Zealand (n=20) and Hawai'i (n=30).  The data was gathered over the 1994-1996 period.  The two settings have some commonalities and differences.  In both settings Māori are required to make decisions about the continuity of their ethnic Māori identities and hereditary cultural identities of iwi, hapu and whanau, and the part that they wish these identities to play in their daily lives.  The focus of this research was about how Māori create meaning in their lives and maintain their social identities across and within those contexts they move through. 

The findings of this research suggest that Māori in New Zealand continue to value and gain meaning and satisfaction from their cultural collectivities and the social identities derived from them.  However, the results tend to suggest that there are changes in the ways that individuals conceptualise these identities and concomitantly, how they see of themselves.
For New Zealand participants, conceptions of hapu and iwi appear to be converging with an increasing focus on the physicality of marae, its environment and symbolism, and the social events and relationships negotiated in that space.  New Zealand participants saw some hapu and iwi maintenance activities as more legitimate than others.  More value was placed on returning to hapu and iwi homelands however irregular these returns were.  In contrast, conceptions of hapu and iwi held by participants in Hawai'i seemed less intense.  There were few opportunities to engage with other hapu or iwi members.  Being Māori had greater meaning and was understood, probed and valued by others in the culturally plural context of Hawai'i.  For New Zealand participants, being Māori was enacted in the context of being a discriminated, negatively constructed minority.  All were aware of the defining effect that the presence of a dominant majority could have and countered these effects by engaging in social justice and in-group solidarity activities.

The changing identity conceptions held by members of Māori social groups will have implications for a sense of community and social cohesion, for tribal asset management, service delivery and crown settlement processes.  If Māori are redefining and renegotiating their social identities to achieve greater meaning and satisfaction then these changes are important to respond to and recognise.

year: 2007