Author Keywords: Neuroptera; Myrmeleontidae; Cueta trivirgata; ants; Ocymyrmex robustior; micro-climate; diet; behaviour; heat torpor; Namib Desert 相似文献
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1.
Late Quaternary climate change,relict populations and present‐day refugia in the northern Atacama Desert: a case study from Quebrada La Higuera (18° S) 下载免费PDF全文
2.
Keith T. Killingbeck 《Plant and Soil》2008,304(1-2):145-155
Paradoxically low nitrogen resorption efficiency in the drought-deciduous desert shrub Fouquieria splendens Engelm (ocotillo) triggered tests of the hypotheses that resorption is often low in this species and that resorption is influenced
by zinc. Resorption efficiency and proficiency were measured in 1989 and 1994 at two sites in the Chihuahuan Desert in plants
to which zinc, or zinc and nitrogen were added. Resorption of nitrogen, phosphorus, and zinc in unfertilized plants varied
temporally and spatially, but was both efficient (66%, 49%, and 40%, respectively) and proficient (0.55%, 0.09%, and 9.4 μg
g−1, respectively) as determined by comparison to worldwide resorption patterns in a wide variety of other species. Applications
of zinc had no significant effect on the resorption of nitrogen and phosphorus, but did influence the resorption of zinc.
Resorption of zinc was significantly less efficient in zinc-treated plants than controls at only one of the two sites in one
of the 2 years, yet resorption of zinc was significantly less proficient in zinc-treated plants than controls in both years
and at both sites. This pattern of zinc resorption adds insight into the continuing debate regarding the relationship between
fertility and resorption because the data used to fuel the debate have almost exclusively described macronutrients, not trace
metals. The high variability in resorption among individuals, sites, and years observed for F. splendens may well be an attribute of many desert-dwelling, drought-deciduous plants. When senescence is controlled primarily by water
availability rather than photoperiod, especially in a landscape characterized by unpredictable amounts and timing of precipitation,
high variability in associated processes such as resorption may be inevitable. 相似文献
3.
Juan Viruel Pilar Catalán José Gabriel Segarra‐Moragues 《Journal of Biogeography》2012,39(6):1073-1085
Aim The Chilean endemic Dioscorea biloba (Dioscoreaceae) is a dioecious geophyte that shows a remarkable 600 km north–south disjunction in the peripheral arid area of the Atacama Desert. Its restricted present‐day distribution and probable Neogene origin indicate that its populations have a history linked to that of the Atacama Desert, making this an ideal model species with which to investigate the biogeography of the region. Location Chile, Atacama Desert and peripheral arid area. Methods Two hundred and seventy‐five individuals from nine populations were genotyped for seven nuclear microsatellite loci, and plastid trnL–F and trnT–L sequences were obtained for a representative subset of these. Analyses included the estimation of genetic diversity and population structure through clustering, Bayesian and analysis of molecular variance analyses, and statistical parsimony networks of chloroplast haplotypes. Isolation by distance was tested against alternative dispersal hypotheses. Results Microsatellite markers revealed moderate to high levels of genetic diversity within populations, with those from the southern Limarí Valley showing the highest values and northern populations showing less exclusive alleles. Bayesian analysis of microsatellite data identified three genetic groups that corresponded to geographical ranges. Chloroplast phylogeography revealed no haplotypes shared between northern and southern ranges, and little haplotype sharing between the two neighbouring southern valleys. Dispersal models suggested the presence of extinct hypothetical populations between the southern and northern ranges. Main conclusions Our results are consistent with prolonged isolation of the northern and southern groups, mediated by the life‐history traits of the species. Significant isolation was revealed at both large and moderate distances as gene flow was not evident even between neighbouring valleys. Bayesian analyses of microsatellite and chloroplast haplotype diversity identified the southern area of Limarí as the probable area of origin of the species. Our data do not support recent dispersal of D. biloba from the southern range into Antofagasta, but indicate the fragmentation of an earlier wider range, concomitant with the Pliocene–Pleistocene climatic oscillations, with subsequent extinctions of the Atacama Desert populations and the divergence of the peripheral ones as a consequence of genetic drift. 相似文献
4.
Theoretical models of species coexistence between desert mammals have generally been based on a combination of food and microhabitat selection by granivorous rodents. Although these models are applicable in various deserts of the world, they cannot explain resource use by mammals in Neotropical deserts. The present study examines diet composition in a mammal assemblage in the Monte desert, Argentina. The results show that two main strategies are used by these mammals: medium‐sized species (hystricognath rodents: Dolichotis patagonum, Lagostomus maximus, Microcavia australis and Galea musteloides; and an exotic lagomorph: Lepus europaeus) are herbivores, whereas small‐sized species (a marsupial: Thylamys pusillus; and sigmodontine rodents: Graomys griseoflavus, Akodon molinae, Calomys musculinus, Eligmodontia typus) are omnivorous. Small mammals also show a tendency towards granivory (C. musculinus), insectivory (A. molinae and T. pusillus) and folivory (G. griseoflavus). 相似文献
5.
《Saudi Journal of Biological Sciences》2022,29(1):650-659
Sporadic rains in the Atacama Desert reveal a high biodiversity of plant species that only occur there. One of these rare species is the “Red añañuca” (Zephyranthes phycelloides), formerly known as Rhodophiala phycelloides. Many species of Zephyranthes in the Atacama Desert are dangerously threatened, due to massive extraction of bulbs and cutting of flowers. Therefore, studies of the biodiversity of these endemic species, which are essential for their conservation, should be conducted sooner rather than later. There are some chloroplast genomes available for Amaryllidaceae species, however there is no complete chloroplast genome available for any of the species of Zephyranthes subgenus Myostemma. The aim of the present work was to characterize and analyze the chloroplast of Z. phycelloides by NGS sequencing. The chloroplast genome of the Z. phycelloides consists of 158,107 bp, with typical quadripartite structures: a large single copy (LSC, 86,129 bp), a small single copy (SSC, 18,352 bp), and two inverted repeats (IR, 26,813 bp). One hundred thirty-seven genes were identified: 87 coding genes, 8 rRNA, 38 tRNA and 4 pseudogenes. The number of SSRs was 64 in Z. phycelloides and a total of 43 repeats were detected. The phylogenetic analysis of Z. phycelloides shows a distinct subclade with respect to Z. mesochloa. The average nucleotide variability (Pi) between Z. phycelloides and Z. mesochloa was of 0.02000, and seven loci with high variability were identified: psbA, trnSGCU-trnGUCC, trnDGUC-trnYGUA, trnLUAA-trnFGAA, rbcL, psbE-petL and ndhG-ndhI. The differences between the species are furthermore confirmed by the high amount of SNPs between these two species. Here, we report for the first time the complete cp genome of one species of the Zephyranthes subgenus Myostemma, which can be used for phylogenetic and population genomic studies. 相似文献
6.
Solitary and paired adult (nine) and subadult (one) male chacma baboons, Papio ursinus, were observed over a period of years living in part of a wooded desert canyon not used by adjacent troops. These extratroop males were silent when alone and gave only one alarm vocalization, the “wa-hoo” call, when paired. The space occupied by them is unsuitable for use by troops according to criteria for adequate sleeping sites and access to water. But the foods available to them, especially figs, but also other fruits and fresh acacia seeds, were abundant. These foods are more highly preferred by baboons than those foods available to troop members. Troop members deplete these resources and shift to less preferred foods with lower water content and longer processing times. All of the adult members of the troop adjacent to these isolated males were infected with a skin disease. Isolated males were not so afflicted and so cannot have originated from, or ever been a part of, this troop. They probably moved to the space where they were observed from other inland troops, traveling to their current home range along the narrow canyon river course. 相似文献
7.
Alan Clive Marsh 《Journal of thermal biology》1987,12(4):295-300
1. 1.Cueta trivirgata larvae construct pits in the dry Kuiseb River bed in the Namib Desert.
2. 2.An art, Ocymyrmex robustior comprises 65.4% of the biomass of prey consumed by the ant-lions.
3. 3.O. robustior is active between surface temperatures of 27–68°C.
4. 4.Ant-lions tolerate high body temperatures (LD50 = 53.4°C).
5. 5.By exploiting the pit microclimate and by digging below the surface during extreme thermal loads, ant-lions can capture prey at surface temperatures of 13–63°C.
6. 6.These behavioural and physiological adaptations enable ant-lions to maximize the duration of vigilance and hence prey capture success.
8.
9.
I. D. PULFORD K. J. MURPHY G. DICKINSON J. A. BRIGGS I. SPRINGUEL 《Botanical journal of the Linnean Society. Linnean Society of London》1992,108(2):131-141
PULFORD, I. D., MURPHY, K. J., DICKINSON, G., BRIGGS, J. A. & SPRINGUEL, I., 1992. Ecological resources for conservation and development in Wadi Allaqi, Egypt. The creation of Lake Nasser behind the Aswan High Dam on the River Nile has brought about significant environmental changes in Upper Egypt. A multidisciplinary project was started in 1987 to assess the environmental changes associated with periodic inundation in desert ecosystems. The data presented here provide a baseline for studies aimed at assessing the potential for, and ecological impacts of, sustainable development in the target area, and may act as a blueprint for wider-scale development. Soil, water, vegetation, animal and human resources are being monitored. There has been a major increase in plant communities dominated by riverain species, at the expense of the original desert wadi vegetation. The water has attracted human settlement, with some 200–250 people now living in the wadi. The inherent high fertility of the soil has allowed them to grow a range of crops in small plots, using a system of shifting cultivation dictated by the lake water level. While this degree of development may be sustainable, larger-scale development of the fragile wadi ecosystem demands a full assessment of appropriate management techniques. 相似文献
10.
R. C. Garrick C. A. Meadows A. N. Nicolas J. D. Nason R. J. Dyer 《Conservation Genetics》2008,9(6):1673-1676
We developed seven nuclear intron markers for Euphorbia lomelii. New exon-primed intron-crossing (EPIC) oligonucleotides were used for initial amplification and sequencing, then locus-specific
primers and restriction-fragment-length polymorphism genotyping assays were designed. Loci showed no significant deviation
from Hardy–Weinberg and linkage equilibrium, and they cross-amplify in at least three congeneric species.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献