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1.
Sub-Antarctic Marion Island has had a permanent research station for 50 years and the islands Wandering Albatrosses have been intensively studied for 20 years. The reactions of breeding birds to approaches by a human on foot were recorded. Three response variables were calculated: intensity of vocal reaction (IVR), intensity of non-vocal reaction (INR) and overall response index (ORI). At 5 m from the nest, twice as many birds stood and/or vocalised as at 15 m. Nearest neighbour distance, age and gender did not explain individual variability of responses. Study colony birds had higher IVR scores than non-study colony birds; birds at colonies closest to the station had the highest ORI scores. A better breeding record was associated with lower IVR and ORI scores, but a causative relationship remains to be demonstrated. A minimum viewing distance of 25 m is recommended for breeding Wandering Albatrosses.
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Marienne S. de VilliersEmail: Fax: +27-21-6503434 |
John CooperEmail: |
Peter G. RyanEmail: |
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T. Ryan Gregory 《Evolution》2009,2(2):156-175
Natural selection is one of the central mechanisms of evolutionary change and is the process responsible for the evolution
of adaptive features. Without a working knowledge of natural selection, it is impossible to understand how or why living things
have come to exhibit their diversity and complexity. An understanding of natural selection also is becoming increasingly relevant
in practical contexts, including medicine, agriculture, and resource management. Unfortunately, studies indicate that natural
selection is generally very poorly understood, even among many individuals with postsecondary biological education. This paper
provides an overview of the basic process of natural selection, discusses the extent and possible causes of misunderstandings
of the process, and presents a review of the most common misconceptions that must be corrected before a functional understanding
of natural selection and adaptive evolution can be achieved.
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T. Ryan GregoryEmail: |
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The recent contribution by Jarmila Kukalová-Peck on Hennigian phylogenetics and hexapod limb evolution is critically evaluated.
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Michael S. Engel (Corresponding author)Email: |
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Natalia V. Ivanova Aron J. Fazekas Paul D. N. Hebert 《Plant Molecular Biology Reporter》2008,26(3):186-198
Many plant species are considered difficult for DNA isolation due to their high concentrations of secondary metabolites such
as polysaccharides and polyphenols. Several protocols have been developed to overcome this problem, but they are typically
time-consuming, not scalable for high throughput and not compatible with automation. Although a variety of commercial kits
are available for plant DNA isolation, their cost is high and these kits usually have limited taxonomic applicability. In
a previous study we developed an inexpensive automation-friendly protocol for DNA extraction from animal tissues. Here we
demonstrate that a similar protocol allows DNA isolation from plants.
相似文献
Natalia V. IvanovaEmail: |
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Patterns of genome size diversity in the ray-finned fishes 总被引:1,自引:0,他引:1
The ray-finned fishes make up about half of all vertebrate diversity and are by far the best represented group in the Animal
Genome Size Database. However, they have traditionally been the least well investigated among vertebrates in terms of patterns
and consequences of genome size diversity. This article synthesizes and expands upon existing information about genome size
diversity in ray-finned fishes. Specifically, compiled data from the Animal Genome Size Database and FishBase are used to
examine the potential patterns of interspecific genome size variability according to ecology, environment, morphology, growth,
physiology, reproduction, longevity, and taxonomic diversity. Polyploidy and haploid genome sizes are considered separately,
revealing differences in their respective consequences. This represents the most comprehensive summary of fish genome size
diversity presented to date, and highlights areas of particular interest to investigate as more data become available.
相似文献
T. Ryan GregoryEmail: |
12.
T. Ryan Gregory 《Evolution》2008,1(3):259-273
The occurrence, generality, and causes of large-scale evolutionary trends—directional changes over long periods of time—have
been the subject of intensive study and debate in evolutionary science. Large-scale patterns in the history of life have also
been of considerable interest to nonspecialists, although misinterpretations and misunderstandings of this important issue
are common and can have significant implications for an overall understanding of evolution. This paper provides an overview
of how trends are identified, categorized, and explained in evolutionary biology. Rather than reviewing any particular trend
in detail, the intent is to provide a framework for understanding large-scale evolutionary patterns in general and to highlight
the fact that both the patterns and their underlying causes are usually quite complex.
相似文献
T. Ryan GregoryEmail: |
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The maintenance of exceptionally high numbers of folk varieties by the Piaroa people of the Venezuelan Amazon is considered.
We cataloged 113 manioc folk varieties, their nomenclature, use and relevant characters, revealing significant insights into
the role of manioc in Piaroa social life. Through a qualitative investigation of the cultivation, processing and symbolic
significance of manioc (Manihot esculenta) in two Piaroa regions over a period of 18 years, we have found that such agrobiodiversity can only be fully explained by
a combination of multiple factors, including pragmatic and ecological considerations, the subtle and complex diversity of
Piaroa manioc preparations and a variety of sociocultural factors, such as manioc’s role as a mediator of social relationships
and as a marker of cultural and social heritage.
相似文献
Stanford ZentEmail: |
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A key point in the analysis of dynamical models of biological systems is to handle systems of relatively high dimensions.
In the present paper we propose a method to hierarchically organize a certain type of piecewise affine (PWA) differential
systems. This specific class of systems has been extensively studied for the past few years, as it provides a good framework
to model gene regulatory networks. The method, shown on several examples, allows a qualitative analysis of the asymptotic
behavior of a PWA system, decomposing it into several smaller subsystems. This technique, based on the well-known strongly
connected components decomposition, is not new. However, its adaptation to the non-smooth PWA differential equations turns
out to be quite relevant because of the strong discrete structure underlying these equations. Its biological relevance is
shown on a 7-dimensional PWA system modeling the gene network responsible for the carbon starvation response in Escherichia coli.
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Laurent Tournier (Corresponding author)Email: |
Jean-Luc GouzéEmail: |
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Peter Godfrey-Smith 《Biology & philosophy》2007,22(3):429-437
Jablonka and Lamb's claim that evolutionary biology is undergoing a ‘revolution’ is queried. But the very concept of revolutionary
change has uncertain application to a field organized in the manner of contemporary biology. The explanatory primacy of sequence
properties is also discussed.
相似文献
Peter Godfrey-SmithEmail: |
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Methanogens growing on C-1 substrates synthesize 2-carbon acetyl groups in the form of acetyl-CoA for carbon assimilation
using the multienzyme complex acetyl-CoA decarbonylase/synthase (ACDS) which contains five different subunits encoded within
an operon. In species growing on acetate ACDS also functions to cleave the acetate C-C bond for energy production by methanogenesis.
A number of species of Methanosarcina that are capable of growth on either C-1 compounds or acetate contain two separate ACDS operons, and questions have been
raised about whether or not these operons play separate roles in acetate synthesis and cleavage. Methanosarcina thermophila genomic DNA was analyzed for the presence of two ACDS operons by PCR amplifications with different primer pairs, restriction
enzyme analyses, DNA sequencing and Southern blot analyses. A single ACDS operon was identified and characterized, with no
evidence for more than one. MALDI mass spectrometric analyses were carried out on ACDS preparations from methanol- and acetate-grown
cells. Peptide fragmentation patterns showed that the same ACDS subunits were present regardless of growth conditions. The
evidence indicates that a single form of ACDS is used both for acetate cleavage during growth on acetate and for acetate synthesis
during growth on C-1 substrates.
Electronic Supplementary Material Supplementary material is available for this article at
相似文献
David A. Grahame (Corresponding author)Email: |
Edward DeMoll (Corresponding author)Email: |
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Douglas Medin Norbert Ross Douglas Cox Scott Atran 《Human ecology: an interdisciplinary journal》2007,35(3):315-329
There is a continuing controversy over Native American fishing and hunting rights. We show that Native American (Menominee)
and European American fish experts have a common knowledge base and share values and attitudes associated with fishing practices
(though organized around different ethical principles). Nonetheless, perceived group differences are dramatic (especially European American perceptions of Native Americans). Cultural differences in models
of nature and associated inference processes appear to mediate these stereotypes and may hold the key to reducing intergroup
conflict over resources.
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Douglas MedinEmail: |
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Philip Richard Sullivan 《Biology & philosophy》2009,24(1):65-79
This paper demonstrates that the human visual system, the primary sensory conduit for primates, processes ambient energy in
a way that obligatorily constructs the objects that we ineluctably perceive. And since our perceptual apparatus processes
information only in terms of objects (along with the properties and movements of objects), we are limited in our ability to comprehend ‘what
is’ when we move beyond our ordinary world of midsize objects—as, for example, when we address the micro microworld of quantum
physics.
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Philip Richard SullivanEmail: |
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Margaret Otlowski 《Journal of bioethical inquiry》2007,4(2):135-150
This paper provides a legal overview of key issues associated with donation of genetic samples and information from a donor
perspective. In particular, it addresses the property status of samples as well as issues in respect of consent, privacy,
commercialisation and benefit sharing. The paper highlights the need for appropriate protection and safeguards for individuals,
but also, importantly, for understanding what donors actually think and want in terms of genetic research and the use of their
samples and information. The paper seeks to emphasise the importance of transparency and accountability in the conduct of
research in order to maximise donor participation and confidence and public trust in general.
相似文献
Margaret OtlowskiEmail: |
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Causal Explanation of Indonesian Forest Fires: Concepts, Applications, and Research Priorities 总被引:1,自引:0,他引:1
Andrew P. Vayda 《Human ecology: an interdisciplinary journal》2006,34(5):615-635
Problems with studies, claims, and assumptions that have been made about the causes of fires in Indonesia's tropical moist forests are identified, and the kinds of concepts, methods, prioritizing, and data needed to resolve the problems are discussed. Separate sections are devoted to studying ignitions, studying fire susceptibility and fire behavior, and using the goal of causal explanation to guide interdisciplinary research.
相似文献
Andrew P. VaydaEmail: |