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1.
Species’ life histories are often classified on a continuum from “fast” to “slow”, yet there is no consistently used definition
of this continuum. For example, some researchers include body mass as one of the traits defining the continuum, others factor
it out by analysing body-mass residuals, a third group performs both of these analyses and uses the terms “fast” and “slow”
in both ways, while still others do not mention body mass at all. Our analysis of European and North American freshwater fish,
mammals, and birds (N = 2,288 species) shows the fundamental differences between life-history patterns of raw data and of body-mass residuals.
Specifically, in fish and mammals, the number of traits defining the continuum decreases if body-mass residuals are analysed.
In birds, the continuum is defined by a different set of traits if body mass is factored out. Our study also exposes important
dissimilarities among the three taxonomic groups analysed. For example, while mammals and birds with a “slow” life history
have a low fecundity, the opposite is true for fish. We conclude that our understanding of life histories will improve if
differences between patterns of raw data and of body-mass residuals are acknowledged, as well as differences among taxonomic
groups, instead of using the “fast–slow continuum” too indiscriminately for any covarying traits that appear to suit the idea. 相似文献
2.
Competitive dominance among sessile marine organisms in a high Arctic boulder community 总被引:1,自引:1,他引:0
In most hard substrate environments, space is a limiting resource for sessile organisms. Competition for space is often high and is a structuring force within the community. In the Beaufort Sea’s Boulder Patch, crustose coralline red algae are major space occupiers. This research determined if coralline algae were competitively dominant over other sessile organisms. To test this hypothesis, overgrowth was documented in terms of “winners” and “losers” on the contact borders between different species. Crustose corallines occurred in over 80% of the observed interactions but were only winners in approximately half of them. Most frequently, bryozoans, tunicates, and sponges were superior competitors over crustose corallines, while at the same time these invertebrate groups were among the least abundant space occupiers. 相似文献
3.
Tea plant [Camellia
sinensis (L.) O.Kuntze)] is one of the most popular non-alcoholic beverage crops in the world today. In recent years, many clonal
tea cultivars have been developed and widely planted to replace the diverse traditional tea populations. In this article,
we study the relationships between classifications based on simple sequence repeat (SSR) markers and on morphological traits
for 185 tea plant cultivars. Results show that the genetic diversity index (H) is between 0.229 and 0.803, and the mean value is 0.543; the observed heterozygosity (H
o) ranges from 0.103 to 0.683, with an average of 0.340, while the genetic identity varies from 0.267 to 0.984. Based on tea-making
properties, the genetic diversity in the “black-green tea” group is much higher than in the “Oolong tea” group. Based on morphological
traits, cluster analysis classifies the 185 cultivars into three groups, “group I,” “group II” and “group III.” Most cultivars
are related based on the geographical origin and their genetic backgrounds. 相似文献
4.
In a 5-ha area of primary lowland rain forest in Borneo, we observed four polydomous colonies of the night-active giant ant
Camponotus gigas. The nonoverlapping, three-dimensional territories in the canopy had a ground size up to 0.8 ha. C. gigas showed a distinct territorial behavior: (1) specific “barrack” nests, especially containing many majors, were situated at
the borders and were established during long-term territorial conflicts; (2) trunk trails were regularly patrolled by majors
that attacked alien conspecifics and some other ant species violently; and (3) sentinels, often involved in long-enduring
conflicts with neighboring ant colonies, defended the borders at bridgeheads. Interspecific conflicts with sympatric Camponotus species always led to violent, “bloody” fights of all castes. Intraspecific conflicts, however, were solved by ritual fights
(“front leg boxing”) of majors. C. gigas performed a de-escalation strategy to end short periods of true intraspecific “ant war” that we provoked experimentally.
Artificially induced ritualized combats continued over weeks also in the absence of baits, indicating that borders may become
established by long-term conflicts of attrition. We discuss the differences between ritual fights in desert and rain-forest
ants and apply Lanchester's theory of battles to our findings.
Received: October 17, 2000 / Accepted: May 14, 2001 相似文献
5.
Personality means suites of correlated behavioural traits, also referred to as “behavioural syndromes” or “personality dimensions”.
Across animal taxa similar combinations of traits seem to prevail, which may have proximate foundation in common neuroendocrine
mechanisms. Hitherto, these have been rarely studied in intact social settings. We investigated personalities of greylag goose
males from a free-roaming flock that shows complex social relationships. In connection with our longitudinal study on the
consistency of behavioural and physiological responses to multiple challenges, we asked whether and how single, personality-related
behavioural traits correlate with each other to form personality dimension(s). We tested whether these dimensions were related
to physiological characteristics that previously showed limited plasticity (heart rate (HR), baseline and stress-induced excreted
immuno-reactive corticosterone (BM), and testosterone metabolites levels) and, furthermore, to age, body measures, and dominance
rank. Principal-components analysis based on behavioural variables revealed two factors: 51.1% of variability was explained
by “aggressiveness” and a further 19.1% by “sociability”. “Aggressiveness” comprised correlated measures of aggression, subordinance,
boldness, vigilance, and proximity to the mate. This “aggressiveness” positively correlated with stress-induced BM levels,
the HR increase during aggressive interactions, and with dominance rank, which may suggest proximate and functional contingencies
of this personality dimension. 相似文献
6.
A classic community assembly hypothesis is that all guilds must be represented before additional species from any given guild
enter the community. We conceptually extend this hypothesis to continuous functional traits, refine the hypothesis with an
eco-evolutionary model of interaction network community assembly, and compare the resultant continuous trait assembly rule
to empirical data. Our extension of the “guild assembly rule” to continuous functional traits was rejected, in part, because
the eco-evolutionary model predicted trait assembly to be characterized by the expansion of trait space and trait/species sorting within trait space. Hence, the guild rule may not be broadly applicable. A “revised” assembly rule
did, however, emerge from the eco-evolutionary model: as communities assemble, the range in trait values will increase to
a maximum and then remain relatively constant irrespective of further changes in species richness. This rule makes the corollary
prediction that the trait range will, on average, be a saturating function of species richness. To determine if the assembly
rule is at work in natural communities, we compared this corollary prediction to empirical data. Consistent with our assembly
rule, trait “space” (broadly defined) commonly saturates with species richness. Our assembly rule may thus represent a general
constraint placed on community assembly. In addition, taxonomic scale similarly influences the predicted and empirically observed
relationship between trait “space” and richness. Empirical support for the model’s predictions suggests that studying continuous
functional traits in the context of eco-evolutionary models is a powerful approach for elucidating general processes of community
assembly. 相似文献
7.
Russell Hopfenberg 《Human ecology: an interdisciplinary journal》2009,37(5):643-651
Human population growth has been identified as a primary cause of ecologically destructive phenomena and, if left unchecked,
will threaten the survivability of the human species. It has been demonstrated that genetic feedback is the mechanism by which
species achieve ecological balance. The present analysis shows the applicability of this mechanism to human population regulation.
In this model, the traits of behavior and culture are explained as following a four step process, similar to, and nested within
genetic evolution. As species extinction is part and parcel of evolution, and environmental circumstances are changing rapidly,
the population regulatory change that would take place on the genetic level of integration would be human extinction. However,
the change on the cultural level, requiring a revision of the social contingency from “food production must be increased to
feed a growing population” to “food production increases cause population increases,” would lead to human sustainability. 相似文献
8.
Fluctuating asymmetry (FA) is small deviations from perfect symmetry in normally bilaterally symmetrical traits. We examined
the relationship between FA of five body traits (ear height, length of three digits, and ankle circumference) and self-reported
scores of physical and verbal aggression in a sample of 90 boys aged 10 to 15 years. The relationships between FA and scores
of aggression (particularly physical aggression) were found to be negative; in other words, the most symmetrical boys showed
highest aggression. One trait (ankle circumference) showed the characteristics of “ideal” FA—parametric mean of zero and a
normal distribution. Mean asymmetries calculated from six repeated measures of ankle FA in 30 subjects taken over a period
of five months showed strong negative associations with scores of physical aggression which were independent of age, height,
and weight.
It is argued that soft tissue “cyclical” FA (as opposed to “fixed” bony FA) is dependent on the secretion of hormones: for
example, cortisol. Causal associations between behavioral traits such as aggresion and hormones will lead to similar correlations
between FA and behavior.
John Manning is a senior lecturer in the School of Biological Sciences at the University of Liverpool. His research interests
are in symmetry as an indicator of good genes, disease resistance, fertility, and hormonal status in human and nonhuman animals.
Daniel Wood has a B.Sc. in anatomy and biology from Liverpool University. At present he is a postgraduate student in the School
of Biological Sciences. His research interests are in fluctuating asymmetry and its behavioral correlates in adolescent boys. 相似文献
9.
Madoka Y Kashiwagi T Hirotsu N Ishimaru K 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2008,116(5):603-612
Rice (Oryza sativa L.) chromosome segment substitution lines (CSSLs), in which chromosomal segments of the Indian landrace “Kasalath” replace
the corresponding endogenous segments in the genome of the Japanese premium rice “Koshihikari”, are available and together
cover the entire genome. Chromosome regions affecting a trait (CRATs) can be identified by comparison of phenotypes with genotypes of CSSLs. We detected 99 CRATs for 15 agronomic
or morphological traits. “Kasalath” had positively acting alleles in 53 CRATs. Its CRATs increased panicle number per plant
by up to 23.3%, grain number per panicle by up to 30.8%, and total grain number by up to 15.1%, relative to “Koshihikari”.
CRATs were identified for grain size (grain thickness and width), with positive effects of about 5.0%. A CRAT on chromosome 8
almost doubled the weight of roots in uppermost soil layers compared to “Koshihikari”. Additionally, “Kasalath” possessed
CRATs for higher lodging resistance (reduction in plant height and increase in stem diameter). In some cases, multiple CRATs
were detected in the same chromosome regions. Therefore, CSSLs with these chromosome segments might be useful breeding materials
for the simultaneous improvement of multiple traits. Five CRATs, one for plant height on chromosome 1, one for stem diameter
on chromosome 8, and three for heading date on chromosomes 6, 7, and 8 overlapped with the corresponding QTLs that already
had been mapped with back-crossed inbred lines of “Nipponbare” and “Kasalath”. In both “Koshihikari” CRATs and “Nipponbare”
QTLs, “Kasalath” had similar effects.
Both Y. Madoka and T. Kashiwagi have contributed equally to this article. 相似文献
10.
Five traits of early child development were studied in 656 infants from the day of birth till 2 years of age. The infants
selected for follow-up were born at 26–42 weeks of gestational age and with a birth weight accordingly ranging from 860 to
4560g. Analysis of variance was carried out for each of the following five traits which entailed the age at which a child:
1) turned himself over (turned); 2) sat unsupported for a few seconds (sat); 3) stood up (stood); 4) walked unsupported (walked);
and 5) cut its first tooth (tooth). The results of this survey show no significant sex differences in the age of initial occurrence
of any of the studied traits. Comparison with older siblings of the surveyed infants indicated a significant sibling resemblance
component for all 5 trais, with the respective intraclass correlation coefficients ranging between 0.34 and 0.53. Gestational
age and birth weight, but not “tooth”, appeared to be important messages of an infant's motor development, insofar as onset
of the studied traits. The separate correlations of “turned”, “sat”, “stood” and “walked” with gestational age or weight were
all negative and statistically highly significant.
Research Unit — Human Population Biology, Division of Anatomy and Anthropology 相似文献
11.
Plants have traits against herbivory that may occur together and increase defense efficiency. We tested whether there are
defense syndromes in a cerrado community and, if so, whether there is a phylogenetic signal in them. We measured nine defense
traits from a woodland cerrado community in southeastern Brazil. We tested the correlation between all pairs of traits and
grouped the species into defense syndromes according to their traits. Most pairwise correlations of traits were complementary.
Plants with lower specific leaf area also presented tougher leaves, with low nitrogen, more trichomes, and tannins. We found
five syndromes: two with low defenses and high nutritional quality, two with high defenses and low nutritional quality, and
one with traits compensating each other. There were two predominant strategies against herbivory in cerrado: “tolerance” and
“low nutritional quality” syndromes. Phylogeny did not determine the suite of traits species presented. We argue that herbivory
exerts significant selection pressure on these plant defense traits. 相似文献
12.
Jing Zhang Yan Liu Dan Yu Hongze Song Jingjin Cui Tao Liu 《Journal of applied phycology》2011,23(2):165-171
Hybridization of gametophytes, continuous self-crossing and targeted selection were utilized to breed a new Laminaria variety. After five-generation selection breeding, the new variety “Rongfu” was obtained. Its male parent “Yuanza No.10”
was the high-yield cultivation variety, and its female parent was variety “Fujian” which could tolerate relatively high seawater
temperature. “Yuanza No.10” and “Fujian” were different but complement in their morphological characteristics and biological
habits. Variety “Rongfu” was bred through their hybridization which exhibited high-yield potential and high seawater temperature
tolerance. The results of traits evaluation in consecutive years showed that “Rongfu” attained higher yields by 24–27% compared
to the control (widely used commercial variety) and also contained considerable amounts of iodine, mannitol, and algin. When
seawater temperature was 18–21°C, the blade growth of “Rongfu” was maintained and tissue loss by abrasion was significantly
lower than the control. Since the adoption of variety “Rongfu” in 2001, its cultivation areas have been extended to Shandong,
Fujian and Guangdong province and have reached 14,133 ha currently, i.e., almost one-tenth of the total cultivation areas
of Laminaria in China. The results of Random Amplified Polymorphic DNA analysis showed that the relationship between “Rongfu” and other
cultivation varieties in China was very close. 相似文献
13.
Hilary Cunningham 《Dialectical Anthropology》2009,33(2):143-156
This paper explores the complex and often contradictory ways in which state borders, and by extension territorial sovereignty,
have become repoliticized over the past decade. In the 1990s, it was commonplace to describe globalization as auguring a new
post-Westphalian world, one in which the nation-state and territorial forms of state sovereignty were disappearing. Both critics
of and advocates for globalization made claims to a new “borderless world” and “de-territorialization”—though from very different
political vantage points. Yet territorial borders did not become uniformly less salient in the new world orders that emerged
under neoliberalism, and in many cases, the securitization of international borders became more acute. Moreover, particularly post 9-11, states often deepened enforcement measures
at their international boundary lines and “border regimes” have become critical to the expanding securitization of the nation-state
and the capital interest of elites. Antiborder activists circa Seattle and beyond have played a central role in critiquing,
politicizing, and drawing our attention to the border as a site of expanding state power, the logics of capital and the kinds of enclosures that continue to structure deep inequalities
across the globe. 相似文献
14.
Nathalie Gontier 《Evolution》2011,4(3):515-538
It is a popularly held view that Darwin was the first author to draw a phylogenetic tree diagram. However, as is the case
with most popular beliefs, this one also does not hold true. Firstly, Darwin never called his diagram of common descent a
tree. Secondly, even before Darwin, tree diagrams were used by a variety of philosophical, religious, and secular scholars
to depict phenomena such as “logical relationships,” “affiliations,” “genealogical descent,” “affinity,” and “historical relatedness”
between the elements portrayed on the tree. Moreover, historically, tree diagrams themselves can be grouped into a larger
class of diagrams that were drawn to depict natural and/or divine order in the world. In this paper, we trace the historical
roots and cultural meanings of these tree diagrams. It will be demonstrated that tree diagrams as we know them are the outgrowth
of ancient philosophical attempts to find the “true order” of the world, and to map the world “as it is” (ontologically),
according to its true essence. This philosophical idea would begin a fascinating journey throughout Western European history.
It lies at the foundation of the famous “scala naturae,” as well as religious and secular genealogical thinking, especially
in regard to divine, familial (kinship), and linguistic pedigrees that were often depicted by tree images. These scala naturae
would fuse with genealogical, pedigree thinking, and the trees that were the result of this blend would, from the nineteenth
century onward, also include the element of time. The recognition of time would eventually lead to the recognition of evolution
as a fact of nature, and subsequently, tree iconographies would come to represent exclusively the evolutionary descent of
species. 相似文献
15.
Jenks AC 《Culture, medicine and psychiatry》2011,35(2):209-235
The incorporation of “culture” into U.S. biomedicine has been increasing at a rapid pace over the last several decades. Advocates
for “cultural competence” point to changing patient demographics and growing health disparities as they call for improved
educational efforts that train health providers to care for patients from a variety of backgrounds. Medical anthropologists
have long been critical of the approach to “culture” that emerges in cultural competence efforts, identifying an essentialized,
static notion of culture that is conflated with racial and ethnic categories and seen to exist primarily among exotic “Others.”
With this approach, culture can become a “list of traits” associated with various racial and ethnic groups that must be mastered
by health providers and applied to patients as necessary. This article uses an ethnographic examination of cultural competence
training to highlight recent efforts to develop more nuanced approaches to teaching culture. I argue that much of contemporary
cultural competence education has rejected the “list of traits” approach and instead aims to produce a new kind of health
provider who is “open-minded,” willing to learn about difference, and treats each patient as an individual. This shift, however,
can ultimately reinforce behavioral understandings of culture and draw attention away from the social conditions and power
differentials that underlie health inequalities. 相似文献
16.
The settlement of the “Alta Valsesia” during the XIII century by the ethnic group “Walser” coming from the Switzerland region
“Vallese”, left clear historical and cultural traces. In the present study we analysed the “Alagna Valsesia” community (Piedmont).
The aim of this research is to reconstruct the demographic and the matrimonial structure of this cultural and geographic isolate
over three centuries and to evaluate the degree of isolation through the analysis of some biodemographic parameters calculated
on the bases of parish registers, from 1618 to 1899 (1503 marriages). Data on the population dynamics highlighted an early
depopulation, since 1500, than led in 1800 to a decline to population of about 60%, relating to the well known phenomenon
of the leaving of mountainous isolate. The analysis of the marriages shows a low rate of endogamic mating (82%). This rate
reach the highest peak 93% between 1650 and 1659, then it decreases to the minimum values 67% in the middle of 1700. The rates
of consanguineous and isonymic marriages are around 20% and 4–5% respectively, reaching the maximum values during 1800; with
the only exception for the period between 1700 and 1749, when the rates decreases because of a substantial migratory flow.
Inbreeding coefficient stressed out — values between 0,4×10–3 and 2,4×10–3, not so different from the ones reported for other
Italian mountainous isolates. The analysis of the seasonality of marriages high-lighted a strong concentration of marriages
during winter months, particularly in January and February, when works were suspended because of the cold. 相似文献
17.
Patrik Krebs Gianni B. Pezzatti Stefano Mazzoleni Lee M. Talbot Marco Conedera 《Theorie in den Biowissenschaften》2010,129(1):53-69
“Fire regime” has become, in recent decades, a key concept in many scientific domains. In spite of its wide spread use, the
concept still lacks a clear and wide established definition. Many believe that it was first discussed in a famous report on
national park management in the United States, and that it may be simply defined as a selection of a few measurable parameters
that summarize the fire occurrence patterns in an area. This view has been uncritically perpetuated in the scientific community
in the last decades. In this paper we attempt a historical reconstruction of the origin, the evolution and the current meaning
of “fire regime” as a concept. Its roots go back to the 19th century in France and to the first half of the 20th century in
French African colonies. The “fire regime” concept took time to evolve and pass from French into English usage and thus to
the whole scientific community. This coincided with a paradigm shift in the early 1960s in the United States, where a favourable
cultural, social and scientific climate led to the natural role of fires as a major disturbance in ecosystem dynamics becoming
fully acknowledged. Today the concept of “fire regime” refers to a collection of several fire-related parameters that may
be organized, assembled and used in different ways according to the needs of the users. A structure for the most relevant
categories of parameters is proposed, aiming to contribute to a unified concept of “fire regime” that can reconcile the physical
nature of fire with the socio-ecological context within which it occurs. 相似文献
18.
Jamshid J. Tehrani 《Evolution》2011,4(3):390-396
Ever since the publication of The Origin of Species, anthropologists and archaeologists have been in turns enchanted and repulsed by the idea that cultural diversity can be
explained by a Darwinian model of descent with modification. Over the last decade, this debate has intensified following the
publication of a number of studies that have sought to reconstruct cultural histories using modern computational methods of
phylogenetic analysis imported from biology. In this paper, I focus on evolution of tribal textile assemblages in Iran and
Central Asia. Using cladistic phylogenetic analysis, I show that similarities and differences among the assemblages can be
largely explained in terms of descent with modification from ancestral assemblages. Interestingly, the phylogenetic signal
in design characters is just as strong (if not stronger) than the signal in technical characters. This may seem surprising
given that techniques, like genes, are transmitted “vertically” from mothers to daughters whereas designs are frequently transmitted
“horizontally” among peers. However, a closer examination reveals that the transmission of designs between weavers mainly
occurs within, rather than between groups, and that, as in many cultures past and present, there are important constraints
on the latter. This highlights that differences in the ways in which genes and cultural traits are transmitted among individuals
should not be assumed to lead to differences in macro-level patterns of evolution, as many archaeologists and anthropologists
have supposed. 相似文献
19.
Andrea Michaela Bauer F. Hoti M. von Korff K. Pillen J. Léon M. J. Sillanpää 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,119(1):105-123
A common difficulty in mapping quantitative trait loci (QTLs) is that QTL effects may show environment specificity and thus
differ across environments. Furthermore, quantitative traits are likely to be influenced by multiple QTLs or genes having
different effect sizes. There is currently a need for efficient mapping strategies to account for both multiple QTLs and marker-by-environment
interactions. Thus, the objective of our study was to develop a Bayesian multi-locus multi-environmental method of QTL analysis.
This strategy is compared to (1) Bayesian multi-locus mapping, where each environment is analysed separately, (2) Restricted
Maximum Likelihood (REML) single-locus method using a mixed hierarchical model, and (3) REML forward selection applying a
mixed hierarchical model. For this study, we used data on multi-environmental field trials of 301 BC2DH lines derived from a cross between the spring barley elite cultivar Scarlett and the wild donor ISR42-8 from Israel. The
lines were genotyped by 98 SSR markers and measured for the agronomic traits “ears per m2,” “days until heading,” “plant height,”
“thousand grain weight,” and “grain yield”. Additionally, a simulation study was performed to verify the QTL results obtained
in the spring barley population. In general, the results of Bayesian QTL mapping are in accordance with REML methods. In this
study, Bayesian multi-locus multi-environmental analysis is a valuable method that is particularly suitable if lines are cultivated
in multi-environmental field trials.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
20.
Raquel Sánchez-Pérez Federico Dicenta Pedro Martínez-Gómez 《Tree Genetics & Genomes》2012,8(2):379-389
The chilling and heat requirements and flowering time were studied, for 2 years, in an almond progeny from the cross between
the late-flowering French selection “R1000” and the early-flowering Spanish “Desmayo Largueta”. These three temperature-dependent
traits showed quantitative inheritance, although for chilling requirements and flowering time a major gene could be involved,
modified by other minor genes. The results indicate that flowering time is mainly a consequence of the chilling requirements;
heat requirements having a smaller effect. In agreement with the genetic findings, a significant Quantitative Trait Loci (QTL)
for chilling requirements was found in G4 together with other minor QTLs in G1, G3, and G7. For heat requirements, two QTLs
in G2 and G7 were identified. The results also show the high influence of temperature in the expression of the three traits
and their QTL analyses. In addition, QTL analysis for flowering time allowed the identification of one significant QTL in
linkage group 4 (G4) that explained most of the phenotypic variation together with other minor QTLs located in G1, G6, and
G7. 相似文献