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121.
Maeva Judith Orliac Pierre-Olivier Antoine Grégoire Métais Laurent Marivaux Jean-Yves Crochet Jean-Loup Welcomme Syed Rafiqul Hassan Baqri Ghazala Roohi 《Die Naturwissenschaften》2009,96(8):911-920
New dental remains of listriodont suids are described from the lower member of the early to middle Miocene Vihowa Formation
of the Bugti Hills, Pakistan. The material is homogeneous in terms of morphology and dimensions and referred as a whole to
Listriodon guptai Pilgrim, 1926. This species is also mentioned in coeval deposits of the Zinda Pir Dome, Pakistan, dating back to ca. 19 Ma.
The early occurrence of an advanced listriodont in Pakistan constrains the age of acquisition of several characters correlated
to lophodonty within Listriodontini, and raises major questions about the early history of the Old World Listriodontinae.
Strong morphological similarity between Listriodon guptai and the African species Listriodon akatikubas found in the late early Miocene of Maboko (Kenya, ca. 16.5 Ma) suggests that this latter is most probably a migrant originating
from Asia. 相似文献
122.
Pio DV Broennimann O Barraclough TG Reeves G Rebelo AG Thuiller W Guisan A Salamin N 《Conservation biology》2011,25(6):1229-1239
Considering genetic relatedness among species has long been argued as an important step toward measuring biological diversity more accurately, rather than relying solely on species richness. Some researchers have correlated measures of phylogenetic diversity and species richness across a series of sites and suggest that values of phylogenetic diversity do not differ enough from those of species richness to justify their inclusion in conservation planning. We compared predictions of species richness and 10 measures of phylogenetic diversity by creating distribution models for 168 individual species of a species-rich plant family, the Cape Proteaceae. When we used average amounts of land set aside for conservation to compare areas selected on the basis of species richness with areas selected on the basis of phylogenetic diversity, correlations between species richness and different measures of phylogenetic diversity varied considerably. Correlations between species richness and measures that were based on the length of phylogenetic tree branches and tree shape were weaker than those that were based on tree shape alone. Elevation explained up to 31% of the segregation of species rich versus phylogenetically rich areas. Given these results, the increased availability of molecular data, and the known ecological effect of phylogenetically rich communities, consideration of phylogenetic diversity in conservation decision making may be feasible and informative. 相似文献
123.
Contemporary studies on sustainability indicator systems (SISs) typically focus on the technical advancement of indicator construction, on qualitative impacts of indicator programmes and on impacts on governance, decision-making and sustainability as a social construct. Yet, their implementation so far has rarely been addressed, even though monitoring and the use of indicator results fall far behind the number of SISs developed. This study aims at the identification of requirements for the development of and constraints to the implementation of SISs in five Asian cities of developing countries. Interviews with local key actors are held, and a qualitative content analysis is carried out. Findings include evidence on the degree of indicator implementation in the case study cities, a hexagonal model for the classification of requirements and constraints, as well as general conclusions for barriers to the use of SISs. 相似文献
124.
Louchart A 《Die Naturwissenschaften》2008,95(12):1109-1119
During modern birds history, climatic and environmental conditions have evolved on wide scales. In a continuously changing
world, landbirds annual migrations emerged and developed. However, models accounting for the origins of these avian migrations
were formulated with static ecogeographic perspectives. Here I reviewed Cenozoic paleoclimatic and paleontological data relative
to the palearctic–paleotropical long distance (LD) migration system. This led to propose a new model for the origin of LD
migrations, the ‘shifting home’ model (SHM). It is based on a dynamic perspective of climate evolution and may apply to the
origins of most modern migrations. Non-migrant tropical African bird taxa were present at European latitudes during most of
the Cenozoic. Their distribution limits shifted progressively toward modern tropical latitudes during periods of global cooling
and increasing seasonality. In parallel, decreasing winter temperatures in the western Palearctic drove shifts of population
winter ranges toward the equator. I propose that this induced the emergence of most short distance migrations, and in turn
LD migrations. This model reconciliates ecologically tropical ancestry of most LD migrants with predominant winter range shifts,
in accordance with requirements for heritable homing. In addition, it is more parsimonious than other non-exclusive models.
Greater intrinsic plasticity of winter ranges implied by the SHM is supported by recently observed impacts of the present
global warming on migrating birds. This may induce particular threats to some LD migrants. The ancestral, breeding homes of
LD migrants were not ‘northern’ or ‘southern’ but shifted across high and middle latitudes while migrations emerged through
winter range shifts themselves.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献