How does habitat fragmentation affect biodiversity? A controversial question at the core of conservation biology

2019 ◽  
Vol 232 ◽  
pp. 271-273 ◽  
Author(s):  
Abraham J. Miller-Rushing ◽  
Richard B. Primack ◽  
Vincent Devictor ◽  
Richard T. Corlett ◽  
Graeme S. Cumming ◽  
...  
Keyword(s):  
Habitat Fragmentation ◽  
Conservation Biology ◽  
The Core

scholarly journals Diversity and Distribution of Lepidopteran Butterflies in Kota District, Rajasthan

2021 ◽  
Vol 1 (2) ◽  
pp. 24-29
Author(s):  
Manish Kumar Gupta ◽  
◽  
Dr. Anupama Jain
Keyword(s):  
Habitat Fragmentation ◽  
Conservation Biology ◽  
Biological Diversity ◽  
Single Species ◽  
Industrial Area ◽  
Survey Area ◽  
Habitat Ecology ◽  
Applied Ecology ◽  
Agriculture Land ◽  
Index Of Diversity

Understanding the standing point of biodiversity is an integral part of studying habitat ecology in the arena of the applied ecology and conservation biology. Considering this, a study was conducted to understand the biodiversity of the single species, i.e. Lepidoptera in four different sites of Kota district. Four distinct habitat fragmentation sites, Chambal Garden, Ganesh Udhyan, Industrial Area and agriculture land were selected to understand the diversity and distribution of lepidopteran butterfly. As this group of butterfly is considered as “umbrella taxa”, detailed study of its assemblages could be directly correlated with the changes in microclimates in the selected regions. Therefore, diversity of the Lepidoptera was calculated by Simpson’s index of diversity and Shannon-Weiner Index. Among these four areas, Chambal Garden and Ganesh Udhyan are dominated with the Lepidoptera whereas, decline in abundance could be observed remaining two areas. This study indicated a rich and diverse butterfly habitat in the selected survey area, which could be served a s a future referral for measuring and monitoring biological diversity.

Are species genetically more sensitive to habitat fragmentation on the periphery of their range compared to the core? A case study on the sand lizard (Lacerta agilis)

2016 ◽  
Vol 32 (1) ◽  
pp. 131-145 ◽  
Author(s):  
Klaus Henle ◽  
Claudia Andres ◽  
Detlef Bernhard ◽  
Annegret Grimm ◽  
Pavel Stoev ◽  
...  
Keyword(s):  
Habitat Fragmentation ◽  
The Core ◽  
Sand Lizard ◽  
Lacerta Agilis

scholarly journals Atlantic Forest fragmentation affects the genetic variation distribution pattern in blue manakins, Chiroxiphia caudata (Aves, Pipridae)

2018 ◽  
Author(s):  
Leonardo P. Niero ◽  
Mercival R. Francisco ◽  
Bruno H. Saranholi ◽  
Luis F. Silveira ◽  
Pedro M. Galetti Jr
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Gene Flow ◽  
Discriminant Analysis ◽  
Habitat Fragmentation ◽  
Atlantic Forest ◽  
Conservation Biology ◽  
Generalist Species ◽  
Private Alleles ◽  
Forest Biome

Habitat fragmentation is one of the main threats to the biodiversity and one of the main challenges faced by conservation biology. This study assessed the effects of habitat fragmentation on the genetic variability of the blue manakin Chiroxiphia caudata, an endemic bird of Atlantic Forest biome. Nine microsatellite loci were used to analyze individuals from five Atlantic Forest areas. Private alleles were found in all areas. Fst, Dest, Bayesian and Discriminant analysis of principal components (DAPC) indicated that populations are genetically structured, but the distance could not explain the differentiation between areas. The fragmentation and the reduction of gene flow may be acting in order to increase the differentiation between areas. Thus, even a generalist species may be affected by habitat fragmentation. Despite this, the whole complex of fragmented areas in Atlantic Forest appears to play an important role for the blue manakin by sheltering its genetic diversity as a whole.

scholarly journals Atlantic Forest fragmentation affects the genetic variation distribution pattern in blue manakins, Chiroxiphia caudata (Aves, Pipridae)

2018 ◽  
Author(s):  
Leonardo P. Niero ◽  
Mercival R. Francisco ◽  
Bruno H. Saranholi ◽  
Luis F. Silveira ◽  
Pedro M. Galetti Jr
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Gene Flow ◽  
Discriminant Analysis ◽  
Habitat Fragmentation ◽  
Atlantic Forest ◽  
Conservation Biology ◽  
Generalist Species ◽  
Private Alleles ◽  
Forest Biome

Habitat fragmentation is one of the main threats to the biodiversity and one of the main challenges faced by conservation biology. This study assessed the effects of habitat fragmentation on the genetic variability of the blue manakin Chiroxiphia caudata, an endemic bird of Atlantic Forest biome. Nine microsatellite loci were used to analyze individuals from five Atlantic Forest areas. Private alleles were found in all areas. Fst, Dest, Bayesian and Discriminant analysis of principal components (DAPC) indicated that populations are genetically structured, but the distance could not explain the differentiation between areas. The fragmentation and the reduction of gene flow may be acting in order to increase the differentiation between areas. Thus, even a generalist species may be affected by habitat fragmentation. Despite this, the whole complex of fragmented areas in Atlantic Forest appears to play an important role for the blue manakin by sheltering its genetic diversity as a whole.

Forty years of bias in habitat fragmentation research

2017 ◽  
Author(s):  
Lenore Fahrig
Keyword(s):  
Habitat Fragmentation ◽  
Habitat Loss ◽  
Conservation Biology ◽  
Habitat Destruction ◽  
The Body ◽  
Positive Effects ◽  
Major Threat ◽  
The Common ◽  
Per Se

This chapter evaluates biases that contribute to the common misrepresentation of fragmentation as a major threat to biodiversity. The idea that habitat fragmentation seriously threatens biodiversity is so widespread that it might be considered a “conservation biology principle.” However, effects attributed to habitat fragmentation are usually confounded with effects of habitat loss. A recent review of the effects of habitat fragmentation per se (effects independent of habitat loss) indicated that 76% of significant effects of fragmentation were positive, and in no situation were most effects negative. Comparing the abstracts of papers with the actual results reported in the body of each paper revealed that fewer than half of the authors who found only positive fragmentation effects actually discuss these positive effects in their abstracts. Thus, authors themselves reinforce the misrepresentation of the fragmentation literature, potentially because authors fear that their results could be incorrectly used to justify habitat destruction.

What face familiarity feelings say about the lateralization of specific entities within the core system

2019 ◽  
Vol 42 ◽  
Author(s):  
Guido Gainotti
Keyword(s):  
Temporal Lobe ◽  
Memory System ◽  
Core System ◽  
The Core ◽  
Memory Traces ◽  
Specific Memory ◽  
Target Article ◽  
Temporal Structures ◽  
The Right

Abstract The target article carefully describes the memory system, centered on the temporal lobe that builds specific memory traces. It does not, however, mention the laterality effects that exist within this system. This commentary briefly surveys evidence showing that clear asymmetries exist within the temporal lobe structures subserving the core system and that the right temporal structures mainly underpin face familiarity feelings.

A scanning electron microscopic study on dissolving process of cholesterol gallstones by chenodeoxycholic acid (CDCA)

1978 ◽  
Vol 36 (2) ◽  
pp. 522-523
Author(s):  
T. Kanetaka ◽  
M. Cho ◽  
S. Kawamura ◽  
T. Sado ◽  
K. Hara
Keyword(s):  
Electron Microscope ◽  
Chenodeoxycholic Acid ◽  
Outer Surface ◽  
Electron Microscopic ◽  
Cholesterol Gallstones ◽  
The Core ◽  
Scanning Electron Microscopic Study ◽  
Scanning Electron Microscopic ◽  
Acceleration Voltage ◽  
Scanning Electron

The authors have investigated the dissolution process of human cholesterol gallstones using a scanning electron microscope(SEM). This study was carried out by comparing control gallstones incubated in beagle bile with gallstones obtained from patients who were treated with chenodeoxycholic acid(CDCA).The cholesterol gallstones for this study were obtained from 14 patients. Three control patients were treated without CDCA and eleven patients were treated with CDCA 300-600 mg/day for periods ranging from four to twenty five months. It was confirmed through chemical analysis that these gallstones contained more than 80% cholesterol in both the outer surface and the core.The specimen were obtained from the outer surface and the core of the gallstones. Each specimen was attached to alminum sheet and coated with carbon to 100Å thickness. The SEM observation was made by Hitachi S-550 with 20 kV acceleration voltage and with 60-20, 000X magnification.

The Structure and Development of Microbodies in the Fat Body and other Tissues of an Insect (Calpodes Ethlius)

1970 ◽  
Vol 28 ◽  
pp. 148-149
Author(s):  
M. Locke ◽  
J. T. McMahon
Keyword(s):  
Electron Microscopy ◽  
Liquid Crystals ◽  
Fat Body ◽  
Competitive Inhibitor ◽  
Dense Core ◽  
Urate Oxidase ◽  
Blood Proteins ◽  
Free Base ◽  
The Core ◽  
The Matrix

The fat body of insects has always been compared functionally to the liver of vertebrates. Both synthesize and store glycogen and lipid and are concerned with the formation of blood proteins. The comparison becomes even more apt with the discovery of microbodies and the localization of urate oxidase and catalase in insect fat body.The microbodies are oval to spherical bodies about 1μ across with a depression and dense core on one side. The core is made of coiled tubules together with dense material close to the depressed membrane. The tubules may appear loose or densely packed but always intertwined like liquid crystals, never straight as in solid crystals (Fig. 1). When fat body is reacted with diaminobenzidine free base and H2O2 at pH 9.0 to determine the distribution of catalase, electron microscopy shows the enzyme in the matrix of the microbodies (Fig. 2). The reaction is abolished by 3-amino-1, 2, 4-triazole, a competitive inhibitor of catalase. The fat body is the only tissue which consistantly reacts positively for urate oxidase. The reaction product is sharply localized in granules of about the same size and distribution as the microbodies. The reaction is inhibited by 2, 6, 8-trichloropurine, a competitive inhibitor of urate oxidase.

Exsolution and inversion in pigeonite from the Whin Sill, Northern England

1978 ◽  
Vol 36 (1) ◽  
pp. 474-475
Author(s):  
P.P.K. Smith
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Homogeneous Nucleation ◽  
Silicate Mineral ◽  
Antiphase Boundaries ◽  
Two Phase ◽  
Primitive Form ◽  
The Core ◽  
Nucleation Mechanisms ◽  
And Inversion

Grains of pigeonite, a calcium-poor silicate mineral of the pyroxene group, from the Whin Sill dolerite have been ion-thinned and examined by TEM. The pigeonite is strongly zoned chemically from the composition Wo8En64FS28 in the core to Wo13En34FS53 at the rim. Two phase transformations have occurred during the cooling of this pigeonite:- exsolution of augite, a more calcic pyroxene, and inversion of the pigeonite from the high- temperature C face-centred form to the low-temperature primitive form, with the formation of antiphase boundaries (APB's). Different sequences of these exsolution and inversion reactions, together with different nucleation mechanisms of the augite, have created three distinct microstructures depending on the position in the grain.In the core of the grains small platelets of augite about 0.02μm thick have farmed parallel to the (001) plane (Fig. 1). These are thought to have exsolved by homogeneous nucleation. Subsequently the inversion of the pigeonite has led to the creation of APB's.

Intramitochondrial Viruses of Reptilian Cell Origin

1972 ◽  
Vol 30 ◽  
pp. 318-319
Author(s):  
Philip D. Lunger ◽  
H. Fred Clark
Keyword(s):  
Particle Production ◽  
Outer Zone ◽  
Density Variation ◽  
Core Region ◽  
Mitochondrial Membranes ◽  
Virus Particles ◽  
The Core ◽  
Vipera Russelli ◽  
Maturation Stages ◽  
Type Particle

In the course of fine structure studies of spontaneous “C-type” particle production in a viper (Vipera russelli) spleen cell line, designated VSW, virus particles were frequently observed within mitochondria. The latter were usually enlarged or swollen, compared to virus-free mitochondria, and displayed a considerable degree of cristae disorganization.Intramitochondrial viruses measure 90 to 100 mμ in diameter, and consist of a nucleoid or core region of varying density and measuring approximately 45 mμ in diameter. Nucleoid density variation is presumed to reflect varying degrees of condensation, and hence maturation stages. The core region is surrounded by a less-dense outer zone presumably representing viral capsid.Particles are usually situated in peripheral regions of the mitochondrion. In most instances they appear to be lodged between loosely apposed inner and outer mitochondrial membranes.

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