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1.
The fast-slow paradigm of life history theory has been a popular approach to individual differences in the evolutionary behavioral sciences. Currently, however, the fast-slow paradigm faces several theoretical and empirical challenges. Motivated by questions regarding the validity of certain assumptions of the paradigm, the current study provides an empirical investigation of human female “fast” versus “slow” strategies. In a sample of 1867 women recruited using MTurk, we use structural equation modeling (SEM) to test whether childhood exposure to different environmental variables had unique effects on proposed life history traits, whether mediated by—or independent of—pubertal timing. Models also test whether the proposed life history traits covary with one another as expected by the paradigm. Data reveal that exposure to violence and poor health in particular, but not environmental harshness or unpredictability in general, had significant effects on pubertal timing. Pubertal timing appeared to mediate effects of childhood environments on age at sexual debut, but not any other adult outcome (e.g., sociosexual orientations, reproductive outcomes). Some associations with mating strategies were incompatible with assumptions of the prevailing fast-slow paradigm; for instance, greater short-term mating orientation was positively associated with childhood socioeconomic status and negatively associated with offspring number. These results highlight the need for a new or revised theoretical approach to understanding developmental, mating, and reproductive strategies.  相似文献   

2.
This study of values placed on wildlife by Bantu and Yaka Pygmy forest dwellers (n = 200) in Northern Congo identified and analyzed two wildlife value orientations - “anthropocentric” and “biocentric.” The former, strongly displayed across all segments of both societies, was likely motivated by heavy reliance on bushmeat and human–wildlife conflicts, and was linked to attitudes approving the killing of animals for human benefit. The “biocentric” orientation was more common among formally educated male respondents who do not hunt and positively linked to attitudes favoring conservation. Wildlife management strategies should consider including 1) sustainable local wildlife exploitation, 2) livelihood projects that provide a real alternative to hunting, and 3) human–wildlife conflict mitigation.  相似文献   

3.
The transdiagnostic expression of psychotic experiences in common mental disorder (anxiety/depression/substance use disorder) is associated with a poorer prognosis, and a small minority of people may indeed develop a clinical picture that meets criteria for schizophrenia. However, it appears neither useful nor valid to observe early states of multidimensional psychopathology in young people through the “schizo”‐prism, and apply misleadingly simple, unnecessary and inefficient binary concepts of “risk” and “transition”. A review of the “ultra‐high risk” (UHR) or “clinical high risk” (CHR) literature indicates that UHR/CHR samples are highly heterogeneous and represent individuals diagnosed with common mental disorder (anxiety/depression/substance use disorder) and a degree of psychotic experiences. Epidemiological research has shown that psychotic experiences are a (possibly non‐causal) marker of the severity of multidimensional psychopathology, driving poor outcome, yet notions of “risk” and “transition” in UHR/CHR research are restrictively defined on the basis of positive psychotic phenomena alone, ignoring how baseline differences in multidimensional psychopathology may differentially impact course and outcome. The concepts of “risk” and “transition” in UHR/CHR research are measured on the same dimensional scale, yet are used to produce artificial diagnostic shifts. In fact, “transition” in UHR/CHR research occurs mainly as a function of variable sample enrichment strategies rather than the UHR/CHR “criteria” themselves. Furthermore, transition rates in UHR/CHR research are inflated as they do not exclude false positives associated with the natural fluctuation of dimensional expression of psychosis. Biological associations with “transition” thus likely represent false positive findings, as was the initial claim of strong effects of omega‐3 polyunsatured fatty acids in UHR samples. A large body of UHR/CHR intervention research has focused on the questionable outcome of “transition”, which shows lack of correlation with functional outcome. It may be more productive to consider the full range of person‐specific psychopathology in all young individuals who seek help for mental health problems, instead of “policing” youngsters for the transdiagnostic dimension of psychosis. Instead of the relatively inefficient medical high‐risk approach, a public health perspective, focusing on improved access to a low‐stigma, high‐hope, small scale and youth‐specific environment with acceptable language and interventions may represent a more useful and efficient strategy.  相似文献   

4.
Dehydroepiandrosterone (DHEA) and cortisol are the most abundant hormones of the human fetal and adult adrenals released as end products of a tightly coordinated endocrine response to stress. Together, they mediate short- and long-term stress responses and enable physiological and behavioral adjustments necessary for maintaining homeostasis. Detrimental effects of chronic or repeated elevations in cortisol on behavioral and emotional health are well documented. Evidence for actions of DHEA that offset or oppose those of cortisol has stimulated interest in examining their levels as a ratio, as an alternate index of adrenocortical activity and the net effects of cortisol. Such research necessitates a thorough understanding of the co-actions of these hormones on physiological functioning and in association with developmental outcomes. This review addresses the state of the science in understanding the role of DHEA, cortisol, and their ratio in typical development and developmental psychopathology. A rationale for studying DHEA and cortisol in concert is supported by physiological data on the coordinated synthesis and release of these hormones in the adrenal and by their opposing physiological actions. We then present evidence that researching cortisol and DHEA necessitates a developmental perspective. Age-related changes in DHEA and cortisol are described from the perinatal period through adolescence, along with observed associations of these hormones with developmental psychopathology. Along the way, we identify several major knowledge gaps in the role of DHEA in modulating cortisol in typical development and developmental psychopathology with implications for future research.  相似文献   

5.
In this contribution, we address a major puzzle in the evolution of human material culture: If maturing individuals just learn their parental generation's material culture, then what is the origin of key innovations as documented in the archeological record? We approach this question by coupling a life‐history model of the costs and benefits of experimentation with a niche‐construction perspective. Niche‐construction theory suggests that the behavior of organisms and their modification of the world around them have important evolutionary ramifications by altering developmental settings and selection pressures. Part of Homo sapiens' niche is the active provisioning of children with play objects — sometimes functional miniatures of adult tools — and the encouragement of object play, such as playful knapping with stones. Our model suggests that salient material culture innovation may occur or be primed in a late childhood or adolescence sweet spot when cognitive and physical abilities are sufficiently mature but before the full onset of the concerns and costs associated with reproduction. We evaluate the model against a series of archeological cases and make suggestions for future research.  相似文献   

6.
In this study we examined the effects of long-term selection on early and late reproduction in the bean weevil. The pure lines and the hybrids between the lines within a selection regime were compared for longevity, early and late female fecundity, male mating ability, pre-adult developmental time and wet adult weight. Comparison of hybrid with pure lines provided some evidence for inbreeding despression in the lines from both selection regimes. We found that virgin and mated adults of both sexes from the “old” lines lived longer than “young” line beetles. Comparisons of the hybrid “young” with hybrid “old” lines revealed a trade-off between early and late fecundity of females. For noncompetitive mating ability of males there was no difference between the lines with different rates of senescence when the males were young. But, when the males were older, beetles from the lines selected for delayed senescence expressed superior mating ability. In addition, the “old” line beetles take longer to develop and are heavier than those from “young” line beetles. Although these data suggest that shorter pre-adult developmental time may imply more rapid senescence, there is the possibility of inadvertent selection for rapid development in the “young” lines and this complicates the interpretation of the observed trade-off between the pre-adult and adult performances.  相似文献   

7.
8.
Few studies have examined the impact of childhood attention deficit hyperactivity disorder (ADHD) symptoms on adult ADHD functional outcomes. To address this issue dimensionally, ADHD symptoms in childhood and adulthood and their relation to educational deficits and work disability are studied in a clinical sample of adult patients with previously untreated ADHD. About 250 adults diagnosed systematically with ADHD according to DSM-IV were prospectively recruited. Primary outcomes were high school dropout and being out of the work last year. Childhood ADHD symptoms, sex differences, comorbidities of other mental disorders, and adult ADHD symptoms were examined by historical data, clinician interviews, and questionnaires. High levels of ADHD symptom severity in childhood were related to dropping out of high school [odds ratio (OR) = 3.0], as were higher numbers of hyperactive–impulsive symptoms in childhood. Significantly, more women than men were long-term work disabled (OR = 2.0). After adjusting for age and gender, persisting high levels of ADHD inattention symptoms in adulthood (OR = 2.5), number of comorbid disorders, and particularly anxiety disorders were significantly related to long-term work disability. Childhood hyperactive–impulsive symptoms and overall severity of childhood ADHD symptoms were associated with high school dropout rates; however, persisting ADHD inattention symptoms and comorbid mental disorders in adulthood were more correlated to occupational impairment. These findings underline proposals for studies on early recognition and interventions for ADHD and psychiatric comorbidity. They further suggest that inattentive symptoms be a focus of adult ADHD treatment and that workplace interventions be considered to prevent long-term work disability.  相似文献   

9.
10.
Increasing evidence suggests that micro (mi)RNAs play important roles in various biological process. To evaluate the roles of miRNA in the porcine liver, we investigated the dynamic profiles of microRNAomes using liver tissue from pigs during the embryonic period (embryonic day 90), weaning stage (postnatal day 30), and adult stage (7 years old). A total of 186 unique miRNAs were differentially expressed during liver development. We also identified that 17, 13, and 6 miRNAs were specifically abundant at embryonic day 90, postnatal day 30, and at 7 years, respectively. Besides regulating basic cellular roles in development, miRNAs expressed at the three developmental stages also participated in regulating “embryonic liver development,” “early hepatic growth and generating a functioning liver,” and “energy metabolic processes,” respectively. Our study indicates that miRNAs are extensively involved in liver development, and provides a valuable resource for the further elucidation of miRNA regulatory roles during liver development.  相似文献   

11.
Abstract

Correlative techniques for estimating environmental requirements of species – variably termed ecological niche modeling or species distribution modeling – are becoming very popular tools for ecologists and biogeographers in understanding diverse aspects of biodiversity. These tools, however, are frequently applied in ways that do not fit well into knowledge frameworks in population ecology and biogeography, or into the realities of sampling biodiversity over real-world landscapes. We offer 10 “fixes” – adjustments to typical methodologies that will take into account population ecological and biogeographic frameworks to produce better models.  相似文献   

12.
The opening of the Deux-Ouvertures cave is on the left bank of the Ardèche River, just before the canyon exit on the land of the village of Saint-Martin d’Ardèche in the Southwest of France. Although it has been known since 1896, the deep part of one of the galleries was not discovered until 1985. The surface of this gallery was covered by animal bones, 90% of which belonged to Ursus spelaeus. In 2007, two osseous human fragments were discovered: the distal part of an adult humerus and the diaphysis of a radius belonging to a young individual. These two specimens are the topic of the present paper. Although the date of the humerus (34,440–33,730 cal BP) corresponds to the period when bears frequented the caves, the dates of the diaphysis of the radius (4410–4570 cal BP), found at the heart of the “decorated Paleolithic sector”, lead us to assume that it was transported there, perhaps deliberately. The study of the two human bones originating in the Deux-Ouvertures cave illustrates that the diaphysis of the radius, belonging to a young individual of the Neolithic period, does not exhibit any differences in comparison to modern radii. By contrast, the distal part of the adult humerus, although it is incomplete and altered, is the first example that has been dated in the Ardèche of adult human remains associated with a decorated Paleolithic cave. This specimen, aside perhaps from the width of its median column, is rather slender and does not present any significant difference in relation to other upper Paleolithic humeri.  相似文献   

13.
We used our novel and programmable Porpoise Alarm (PAL, patd.) to synthesize life-like, electronic harbour porpoise communication signals based on those described for captive animals. In the Little Belt, Denmark, we employed PAL (source level 158 ± 1 dB p–p re 1 μPa@1 m; centroid frequency 133 ± 8.5 kHz) to synthesize three aggressive click train types termed “A”, “F3” and “M1” to naive, free-living harbour porpoises. Via theodolite tracking (372 h of total visual effort spread over 10 expeditions) we found that, depending on signal type, porpoises either avoid or become attracted to PAL: Signal types “A” and “F3” are slight deterrents, porpoises increasing minimum range (+23 to 32 m, respectively), whereas “M1” attracts porpoises, reducing range (by ? 29 m). As determined via archival acoustic detectors (AADs), both signals “F3” and “M1” led the animals to significantly intensify their click rate (by +10% and 68%, respectively) while signal “A” led to a significant reduction ( ? 59%). We propose that equipping fishing gear with PAL emitting signal “F3” could potentially reduce porpoise by-catch by increasing (1) awareness through enhanced echolocation and (2) distance to the nets. Detection probability and radius of PAL/AAD tandems could be improved by emitting signal “M1” to focus porpoise echolocation signals on the AAD. The signal may also be useful in luring animals away from hazards, which may be helpful for conservation measures prior to the onset of harmful acoustic activities such as pile-driving, seismic exploration or ammunition clearance.  相似文献   

14.
15.
Parental investment varies in mammalian species, with male care of young being more common in social and monogamous species. Monogamy is commonly observed in canid species, with both males and females, and often “helper” individuals, providing some degree of care for the young. Social units of the swift fox (Vulpes velox), a small North American canid species, usually consist of a male–female pair and occasionally helpers. The role of parental investment and behavior in swift fox society is currently poorly understood. We observed swift fox dens during the pup-rearing season in each of 2 years to evaluate attendance and frequency of visits to natal dens by adult males and females. Female foxes remained at dens longer and visited them more frequently than did male foxes. Female attendance and visitation decreased throughout the pup-rearing season as pups became older and more independent. Environmental factors, including climate and its effect on prey, appeared to contribute to differences in fox behavior between the 2 years. We observed only one fox outside of the breeding pair attending a den in each of the 2 years, both of which were males. We concluded that each of these two foxes were living within the social unit of the male–female pair as a trio, but not serving as a helper and contributing to the care of the pups. Our results increased knowledge of the ecology and behavior of the swift fox, a species of conservation concern in the Great Plains of North America.  相似文献   

16.
Muscle spindles are skeletal muscle mechanoreceptors that provide proprioceptive information to the central nervous system. The human adult masseter muscle has greater number, larger and more complex muscle spindles than the adult biceps. For a better knowledge of muscle diversity and physiological properties, this study examined the myosin heavy chain (MyHC) expression of muscle spindle intrafusal fibres in the human young masseter and young biceps muscles by using a panel of monoclonal antibodies (mAbs) against different MyHC isoforms. Eight MyHC isoforms were detected in both muscles-slow-tonic, I, IIa, IIx, foetal, embryonic, α-cardiac and an isoform not previously reported in intrafusal fibres, termed IIx′. Individual fibres co-expressed 2–6 isoforms. MyHC-slow tonic separated bag1, AS-bag1 and bag2 fibres from chain fibres. Typically, bag fibres also expressed MyHC-I and α-cardiac, whereas chain fibres expressed IIa and foetal. In the young masseter 98 % of bag1 showed MyHC-α cardiac versus 30 % in the young biceps, 35 % of bag2 showed MyHC-IIx′ versus none in biceps, 17 % of the chain fibres showed MyHC-I versus 61 % in the biceps. In conclusion, the result showed fundamental similarities in intrafusal MyHC expression between young masseter and biceps, but also marked differences implying muscle-specific proprioceptive control, probably related to diverse evolutionary and developmental origins. Finding of similarities in MyHC expression between young and adult masseter and biceps muscle spindles, respectively, in accordance with previously reported similarities in mATPase fibre type composition suggest early maturation of muscle spindles, preceding extrafusal fibres in growth and maturation.  相似文献   

17.
Niche areas of ships, such as lateral thruster tunnels, sea chests, and propellers, are often hot spots for the accumulation of biofouling organisms, a potential source of aquatic invasive species. Yet, the relative importance of different niche areas is poorly resolved, in terms of both total surface area and the associated biota (i.e., the species of organisms and their abundances). To address this information gap, a method was developed to estimate the extent of various niche areas in the global fleet of 120,252 commercial ships active between 1999 and 2013. The total niche area for these vessels was estimated to be 32,996 × 103 m2, representing approximately 10% of the total wetted surface area (WSA) available for colonization by biota. Considering the portion of niche areas relative to the total WSA, it was highest for passenger vessels (27%), followed by tugs (25%), and fishing vessels (21%), with niche areas representing a small portion of the WSA for bulk carriers and tankers (7–8%). Examining the different types of niche areas, thruster tunnels had the greatest total extent (10,189 × 103 m2), representing a disproportionately large contribution (>50%) of the total niche area for passenger vessels and tugs compared to other vessel types. This result, combined with the use and cleaning of thrusters, may render them “super-hot spots” of biofouling. The uneven distribution and extent of niche areas across vessels has implications for transfers of organisms and management strategies to reduce invasions associated with the surfaces of ships.  相似文献   

18.
The aim of this study was to provide validity for the Spanish version of the Morningness–Eveningness-Stability Scale – improved (MESSi), a novel evolved assessment of circadian typology which considers the subjective phase and amplitude by morning affect (MA), eveningness (EV) and distinctness (DI; subjective amplitude) sub-scales. Convergence validity of the MESSi with the reduced Morningness–Eveningness Questionnaire (rMEQ) and relationships with the General Health Questionnaire (GHQ-12) and sensitivity to reward and punishment (SR and SP) were analyzed. Two different Spanish samples, young undergraduate students (n = 891, 18–30 years) and adult workers (n = 577, 31–65 years) participated in this study. Exploratory structural equation modeling (ESEM) of MESSi displayed acceptable fit of a three-factors measurement model. Percentiles of the MA, EV and DI sub-scales were obtained for students and adults. The MESSi showed good convergence validity with the rMEQ scores, with a higher correlation coefficient between MA, EV and lower with DI sub-scales. In both, young students and adult workers, MA was negatively related with the GHQ-12 and SP, but the percentage of explained variance (6% and 3%) was lower than the positive correlations between DI, the GHQ-12 and SP (20% and 13%). Morning types presented higher MA and lower EV scores than the other two typologies in both students and adult workers, whereas only differences in DI were found among students (lowest in evening type). Candidates to psychological symptoms and mental disorders (“true cases”), with the clinical cut-off criteria of the GHQ-12, showed lower MA and higher DI in students, whereas only DI was higher for “true cases” among adults. These results supported that subjective amplitude is a factor related to, but also differentiated of, morningness–eveningness (preferred time for a certain activity). The measure of amplitude might be more important than circadian phase in health consequences.  相似文献   

19.
Many animal species attempt to enhance their environments through niche construction or environmental engineering. Such efforts at environmental modification are proposed to play an important and underappreciated role in shaping biotic communities and evolutionary processes. 1 , 2 Homo sapiens is acknowledged as the ultimate niche constructing species in terms of our rich repertoire of ecosystem engineering skills and the magnitude of their impact. We have been trying to make the world a better place—for ourselves—for tens of thousands of years. I argue here that it is within this general context of niche‐construction behavior that our distant ancestors initially domesticated plants and animals and, in the process, first gained the ability to significantly alter the world's environments. The general concept of niche construction also provides the logical link between current efforts to understand domestication being conducted at two disconnected scales of analysis. At the level of individual plant and animal species, on one hand, there recently have been significant advances in our knowledge of the what, when, and where of domestication of an ever‐increasing number of species worldwide. 3 At the same time, large‐scale regional or universal developmental models of the transition to food production continue to be formulated. These incorporate a variety of “macro‐evolutionary” causal variables that may account for why human societies first domesticated plants and animals. 4 , 5 This essay employs the general concept of niche construction to address the intervening question of how, and to connect these two scales of analysis by identifying the general behavioral context within which human societies responded to “macroevolutionary” causal variables and forged new human plant or animal relationships of domestication.  相似文献   

20.
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