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1.
BMC Ecol ; 20(1): 70, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33334346

RESUMO

BACKGROUND: Earlier breeding is one of the strongest responses to global change in birds and is a key factor determining reproductive success. In most studies of climate effects, the focus has been on large-scale environmental indices or temperature averaged over large geographical areas, neglecting that animals are affected by the local conditions in their home ranges. In riverine ecosystems, climate change is altering the flow regime, in addition to changes resulting from the increasing demand for renewable and clean hydropower. Together with increasing temperatures, this can lead to shifts in the time window available for successful breeding of birds associated with the riverine habitat. Here, we investigated specifically how the environmental conditions at the territory level influence timing of breeding in a passerine bird with an aquatic lifestyle, the white-throated dipper Cinclus cinclus. We relate daily river discharge and other important hydrological parameters, to a long-term dataset of breeding phenology (1978-2015) in a natural river system. RESULTS: Dippers bred earlier when winter river discharge and groundwater levels in the weeks prior to breeding were high, and when there was little snow in the catchment area. Breeding was also earlier at lower altitudes, although the effect dramatically declined over the period. This suggests that territories at higher altitudes had more open water in winter later in the study period, which permitted early breeding also here. Unexpectedly, the largest effect inducing earlier breeding time was territory river discharge during the winter months and not immediately prior to breeding. The territory river discharge also increased during the study period. CONCLUSIONS: The observed earlier breeding can thus be interpreted as a response to climate change. Measuring environmental variation at the scale of the territory thus provides detailed information about the interactions between organisms and the abiotic environment.


Assuntos
Hidrologia , Passeriformes , Animais , Cruzamento , Mudança Climática , Ecossistema
2.
Folia Primatol (Basel) ; 91(6): 669-687, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32126549

RESUMO

With 60% of all primate species now threatened with extinction and many species only persisting in small populations in forest fragments, conservation action is urgently needed. But what type of action? Here we argue that restoration of primate habitat will be an essential component of strategies aimed at conserving primates and preventing the extinctions that may occur before the end of the century and propose that primates can act as flagship species for restoration efforts. To do this we gathered a team of academics from around the world with experience in restoration so that we could provide examples of why primate restoration ecology is needed, outline how primates can act as flagship species for restoration efforts of tropical forest, review what little is known about how primate populations respond to restoration efforts, and make specific recommendations of the next steps needed to make restoration of primate populations successful. We set four priorities: (1) academics must effectively communicate both the value of primates and the need for restoration; (2) more research is needed on how primates contribute to forest restoration; (3) more effort must be put into Masters and PhD level training for tropical country nationals; and finally (4) more emphasis is needed to monitor the responses of regenerating forest and primate populations where restoration efforts are initiated. We are optimistic that populations of many threatened species can recover, and extinctions can be prevented, but only if concerted large-scale efforts are made soon and if these efforts include primate habitat restoration.

3.
R Soc Open Sci ; 6(9): 190772, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31598305

RESUMO

African wolves (AWs) are sympatric with endangered Ethiopian wolves (EWs) in parts of their range. Scat analyses have suggested a dietary overlap between AWs and EWs, raising the potential for exploitative competition, and a possible conservation threat to EWs. However, in contrast to that of the well-studied EW, the foraging ecology of AWs remains poorly characterized. Accordingly, we studied the foraging ecology of radio-collared AWs (n = 11 individuals) at two localities with varying levels of anthropogenic disturbance in the Ethiopian Highlands, the Guassa-Menz Community Conservation Area (GMCCA) and Borena-Saynt National Park (BSNP), accumulating 845 h of focal observation across 2952 feeding events. We also monitored rodent abundance and rodent trapping activity by local farmers who experience conflict with AWs. The AW diet consisted largely of rodents (22.0%), insects (24.8%), and goats and sheep (24.3%). Of the total rodents captured by farmers using local traps during peak barley production (July to November) in GMCCA, averaging 24.7 ± 8.5 rodents/hectare/day, 81% (N = 3009) were scavenged by AWs. Further, of all the rodents consumed by AWs, most (74%) were carcasses. These results reveal complex interactions between AWs and local farmers, and highlight the scavenging niche occupied by AWs in anthropogenically altered landscapes in contrast to the active hunting exhibited by EWs in more intact habitats. While AWs cause economic damage to local farmers through livestock predation, they appear to play an important role in scavenging pest rodents among farmlands, a pattern of behaviour which likely mitigates direct and indirect competition with EWs. We suggest two routes to promote the coexistence of AWs and EWs in the Ethiopian highlands: local education efforts highlighting the complex role AWs play in highland ecosystems to reduce their persecution, and enforced protection of intact habitats to preserve habitat preferred by EWs.

4.
Ecol Evol ; 9(11): 6665-6677, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31236251

RESUMO

Translocation of organisms within or outside its native range carries the risk of modifying the community of the recipient ecosystems and induces gene flow between locally adapted populations or closely related species. In this study, we evaluated the genetic consequences of large-scale translocation of cleaner wrasses that has become a common practice within the salmon aquaculture industry in northern Europe to combat sea lice infestation. A major concern with this practice is the potential for hybridization of escaped organisms with the local, recipient wrasse population, and thus potentially introduce exogenous alleles and breaking down coadapted gene complexes in local populations. We investigated the potential threat for such genetic introgressions in a large seminatural mesocosm basin. The experimental setting represented a simulated translocation of corkwing wrasse (Symphodus melops) that occurs on a large scale in the Norwegian salmon industry. Parentage assignment analysis of mesocosm's offspring revealed 30% (195 out of 651 offspring) interbreeding between the two populations, despite their being genetically (F ST = 0.094, p < 0.05) and phenotypically differentiated. Moreover, our results suggest that reproductive fitness of the translocated western population doubled that of the local southern population. Our results confirm that human translocations may overcome the impediments imposed by natural habitat discontinuities and urge for immediate action to manage the genetic resources of these small benthic wrasses.

5.
Proc Natl Acad Sci U S A ; 116(9): 3624-3629, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30808752

RESUMO

Dengue is a climate-sensitive mosquito-borne disease with increasing geographic extent and human incidence. Although the climate-epidemic association and outbreak risks have been assessed using both statistical and mathematical models, local mosquito population dynamics have not been incorporated in a unified predictive framework. Here, we use mosquito surveillance data from 2005 to 2015 in China to integrate a generalized additive model of mosquito dynamics with a susceptible-infected-recovered (SIR) compartmental model of viral transmission to establish a predictive model linking climate and seasonal dengue risk. The findings illustrate that spatiotemporal dynamics of dengue are predictable from the local vector dynamics, which in turn, can be predicted by climate conditions. On the basis of the similar epidemiology and transmission cycles, we believe that this integrated approach and the finer mosquito surveillance data provide a framework that can be extended to predict outbreak risk of other mosquito-borne diseases as well as project dengue risk maps for future climate scenarios.


Assuntos
Vírus da Dengue/patogenicidade , Dengue/epidemiologia , Surtos de Doenças , Mosquitos Vetores/genética , Animais , China , Mudança Climática , Culicidae/patogenicidade , Culicidae/virologia , Dengue/transmissão , Dengue/virologia , Vírus da Dengue/genética , Vetores de Doenças , Modelos Teóricos , Mosquitos Vetores/virologia
6.
Primate Biol ; 6(1): 7-16, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32110714

RESUMO

Black-and-white colobus (Colobus guereza Rüppell, 1835) are arboreal Old World monkeys inhabiting large parts of the deciduous and evergreen forests of sub-Saharan Africa. Two of the eight subspecies of Colobus guereza are endemic to Ethiopia: C. g. gallarum and C. g. guereza. However, the validity of the Ethiopian taxa is debated and observed morphological differences were attributed to clinal variation within C. g. guereza. To date, no molecular phylogeny of the Ethiopian guerezas is available to facilitate their taxonomic classification. We used mitochondrial DNA markers from 94 samples collected across Ethiopia to reconstruct a phylogeny of respective mitochondrial lineages. In our phylogenetic reconstruction, augmented by orthologous sequence information of non-Ethiopian black-and-white colobus from GenBank, we found two major Ethiopian mitochondrial clades, with one being largely congruent with the distribution of C. g. guereza. The second clade was found only at two locations in the eastern part of the putative range of C. g. gallarum. This second lineage clustered with the lowland form, C. g. occidentalis, from central Africa, whereas the C. g. guereza lineages clustered with C. g. caudatus and C. g. kikuyuensis from Kenya and northern Tanzania. These two guereza lineages diverged around 0.7 million years ago. In addition, mitochondrial sequence information does not support unequivocally a distinction of C. g. caudatus and C. g. kikuyuensis. Our findings indicate a previous biogeographic connection between the ranges of C. g. occidentalis and C. g. gallarum and a possible secondary invasion of Ethiopia by members of the C. g. guereza-C. g. caudatus-C. g. kikuyuensis clade. Given these phylogenetic relationships, our study supports the two-taxa hypothesis, making C. g. gallarum an Ethiopian endemic, and, in combination with the taxon's very restricted range, makes it one of the most endangered subspecies of black-and-white colobus.

7.
Proc Natl Acad Sci U S A ; 115(50): E11790-E11797, 2018 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-30478041

RESUMO

Over the last few years, genomic studies on Yersinia pestis, the causative agent of all known plague epidemics, have considerably increased in numbers, spanning a period of about 5,000 y. Nonetheless, questions concerning historical reservoirs and routes of transmission remain open. Here, we present and describe five genomes from the second half of the 14th century and reconstruct the evolutionary history of Y. pestis by reanalyzing previously published genomes and by building a comprehensive phylogeny focused on strains attributed to the Second Plague Pandemic (14th to 18th century). Corroborated by historical and ecological evidence, the presented phylogeny, which includes our Y. pestis genomes, could support the hypothesis of an entry of plague into Western European ports through distinct waves of introduction during the Medieval Period, possibly by means of fur trade routes, as well as the recirculation of plague within the human population via trade routes and human movement.


Assuntos
Pandemias/história , Peste/história , Yersinia pestis/genética , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Europa (Continente)/epidemiologia , Evolução Molecular , Fósseis/microbiologia , Genoma Bacteriano , História Medieval , Humanos , Filogenia , Peste/epidemiologia , Peste/microbiologia , Polimorfismo de Nucleotídeo Único , Fatores de Tempo , Yersinia pestis/classificação
8.
Proc Natl Acad Sci U S A ; 115(41): 10422-10427, 2018 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-30249639

RESUMO

Louse-borne relapsing fever (LBRF) is known to have killed millions of people over the course of European history and remains a major cause of mortality in parts of the world. Its pathogen, Borrelia recurrentis, shares a common vector with global killers such as typhus and plague and is known for its involvement in devastating historical epidemics such as the Irish potato famine. Here, we describe a European and historical genome of B recurrentis, recovered from a 15th century skeleton from Oslo. Our distinct European lineage has a discrete genomic makeup, displaying an ancestral oppA-1 gene and gene loss in antigenic variation sites. Our results illustrate the potential of ancient DNA research to elucidate dynamics of reductive evolution in a specialized human pathogen and to uncover aspects of human health usually invisible to the archaeological record.


Assuntos
Proteínas de Bactérias/genética , Borrelia/genética , Genoma Bacteriano , Metagenômica , Febre Recorrente/genética , Adulto , Animais , Borrelia/classificação , Borrelia/patogenicidade , Criança , Feminino , História do Século XV , Humanos , Filogenia , Febre Recorrente/história , Febre Recorrente/microbiologia , Países Escandinavos e Nórdicos
9.
Evolution ; 72(11): 2325-2342, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30259522

RESUMO

In changing environments, phenotypic traits are shaped by numerous agents of selection. The optimal phenotypic value maximizing the fitness of an individual thus varies through time and space with various environmental covariates. Selection may differ between different life-cycle stages and act on correlated traits inducing changes in the distribution of several traits simultaneously. Despite increasing interests in environmental sensitivity of phenotypic selection, estimating varying selective optima on various traits throughout the life cycle, while considering (a)biotic factors as potential selective agents has remained challenging. Here, we provide a statistical model to measure varying selective optima from longitudinal data. We apply our approach to analyze environmental sensitivity of phenotypic selection on egg-laying date and clutch size throughout the life cycle of a white-throated dipper population. We show the presence of a joint optimal phenotype that varies over the 35-year period, being dependent on altitude and temperature. We also find that optimal laying date is density-dependent, with high population density favoring earlier laying dates. By providing a flexible approach, widely applicable to free-ranging populations for which long-term data on individual phenotypes, fitness, and environmental factors are available, our study improves the understanding of phenotypic selection in varying environments.


Assuntos
Tamanho da Ninhada , Oviposição/fisiologia , Passeriformes/fisiologia , Fenótipo , Fatores Etários , Altitude , Animais , Feminino , Estágios do Ciclo de Vida , Modelos Estatísticos , Noruega , Densidade Demográfica , Temperatura
11.
R Soc Open Sci ; 5(5): 172207, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29892409

RESUMO

Carnivore populations are declining globally due to range contraction, persecution and prey depletion. One consequence of these patterns is increased range and niche overlap with other carnivores, and thus an elevated potential for competitive exclusion. Here, we document competition between an endangered canid, the Ethiopian wolf (EW), and the newly discovered African wolf (AW) in central Ethiopia. The diet of the ecological specialist EW was dominated by rodents, whereas the AW consumed a more diverse diet also including insects and non-rodent mammals. EWs used predominantly intact habitat, whereas AWs used mostly areas disturbed by humans and their livestock. We observed 82 encounters between the two species, of which 94% were agonistic. The outcomes of agonistic encounters followed a territory-specific dominance pattern, with EWs dominating in intact habitat and AWs in human-disturbed areas. For AWs, the likelihood of winning encounters also increased with group size. Rodent species consumed by EWs were also available in the human-disturbed areas, suggesting that these areas could be suitable habitat for EWs if AWs were not present. Increasing human encroachment not only affects the prey base of EWs, but also may impact their survival by intensifying competition with sympatric AWs.

12.
Biol Lett ; 14(6)2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29875207

RESUMO

Intralocus sexual conflicts arise whenever the fitness optima for a trait expressed in both males and females differ between the sexes and shared genetic architecture constrains the sexes from evolving independently towards their respective optima. Such sexual conflicts are commonplace in nature, yet their long-term evolutionary consequences remain unexplored. Using a Bayesian phylogenetic comparative framework, we studied the macroevolutionary dynamics of intersexual trait integration in stalk-eyed flies (Diopsidae) spanning a time frame of more than 25 Myr. We report that increased intensity of sexual selection on male eyestalks is associated with reduced intersexual eyestalk integration, as well as sex-specific rates of eyestalk evolution. Despite this, lineages where males have been under strong sexual selection for millions of years still exhibit high levels of intersexual trait integration. This low level of decoupling between the sexes may indicate that exaggerated female eyestalks are in fact adaptive-or alternatively, that there are strong constraints on reducing trait integration between the sexes. Future work should seek to clarify the relative roles of constraints and selection in contributing to the varying levels of intersexual trait integration in stalk-eyed flies, and in this way clarify whether sexual conflicts can act as constraints on adaptive evolution even on macroevolutionary time scales.


Assuntos
Evolução Biológica , Dípteros/classificação , Caracteres Sexuais , Animais , Dípteros/anatomia & histologia , Olho/anatomia & histologia , Feminino , Masculino , Filogenia , Seleção Genética
13.
Biol Rev Camb Philos Soc ; 93(4): 1813-1831, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29732670

RESUMO

Environmentally transmitted diseases are comparatively poorly understood and managed, and their ecology is particularly understudied. Here we identify challenges of studying environmental transmission and persistence with a six-sided interdisciplinary review of the biology of anthrax (Bacillus anthracis). Anthrax is a zoonotic disease capable of maintaining infectious spore banks in soil for decades (or even potentially centuries), and the mechanisms of its environmental persistence have been the topic of significant research and controversy. Where anthrax is endemic, it plays an important ecological role, shaping the dynamics of entire herbivore communities. The complex eco-epidemiology of anthrax, and the mysterious biology of Bacillus anthracis during its environmental stage, have necessitated an interdisciplinary approach to pathogen research. Here, we illustrate different disciplinary perspectives through key advances made by researchers working in Etosha National Park, a long-term ecological research site in Namibia that has exemplified the complexities of the enzootic process of anthrax over decades of surveillance. In Etosha, the role of scavengers and alternative routes (waterborne transmission and flies) has proved unimportant relative to the long-term persistence of anthrax spores in soil and their infection of herbivore hosts. Carcass deposition facilitates green-ups of vegetation to attract herbivores, potentially facilitated by the role of anthrax spores in the rhizosphere. The underlying seasonal pattern of vegetation, and herbivores' immune and behavioural responses to anthrax risk, interact to produce regular 'anthrax seasons' that appear to be a stable feature of the Etosha ecosystem. Through the lens of microbiologists, geneticists, immunologists, ecologists, epidemiologists, and clinicians, we discuss how anthrax dynamics are shaped at the smallest scale by population genetics and interactions within the bacterial communities up to the broadest scales of ecosystem structure. We illustrate the benefits and challenges of this interdisciplinary approach to disease ecology, and suggest ways anthrax might offer insights into the biology of other important pathogens. Bacillus anthracis, and the more recently emerged Bacillus cereus biovar anthracis, share key features with other environmentally transmitted pathogens, including several zoonoses and panzootics of special interest for global health and conservation efforts. Understanding the dynamics of anthrax, and developing interdisciplinary research programs that explore environmental persistence, is a critical step forward for understanding these emerging threats.


Assuntos
Bacillus anthracis/genética , Bacillus anthracis/fisiologia , Pesquisa Interdisciplinar , Microbiologia do Solo , Esporos Bacterianos , Animais , Antraz/microbiologia , Humanos
14.
Ecol Evol ; 8(8): 4065-4073, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29721280

RESUMO

Interactions between birds and fish are often overlooked in aquatic ecosystems. We studied the influence of Atlantic salmon and brown trout on the breeding population size and reproductive output of the white-throated dipper in a Norwegian river. Acidic precipitation led to the extinction of salmon, but salmon recolonized after liming was initiated in 1991. We compared the dipper population size and reproductive output before (1978-1992) and after (1993-2014) salmon recolonization. Despite a rapid and substantial increase in juvenile salmon, the breeding dipper population size and reproductive output were not influenced by juvenile salmon, trout, or total salmonid density. This might be due to different feeding strategies in salmonids and dippers, where salmonids are mainly feeding on drift, while the dipper is a benthic feeder. The correlation between the size of the dipper population upstream and downstream of a salmonid migratory barrier was similar before and after recolonization, indicating that the downstream territories were not less attractive after the recolonization of salmon. Upstream dipper breeding success rates declined before the recolonization event and increased after, indicating improved water quality due to liming, and increasing invertebrate prey abundances and biodiversity. Surprisingly, upstream the migratory barrier, juvenile trout had a weak positive effect on the dipper population size, indicating that dippers may prey upon small trout. It is possible that wider downstream reaches might have higher abundances of alternative food, rending juvenile trout unimportant as prey. Abiotic factors such as winter temperatures and acidic precipitation with subsequent liming, potentially mediated by prey abundance, seem to play the most important role in the life history of the dipper.

16.
Proc Natl Acad Sci U S A ; 115(4): 750-755, 2018 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-29311333

RESUMO

In this contribution, we develop a theoretical framework for linking microprocesses (i.e., population dynamics and evolution through natural selection) with macrophenomena (such as interconnectedness and modularity within an ecological system). This is achieved by developing a measure of interconnectedness for population distributions defined on a trait space (generalizing the notion of modularity on graphs), in combination with an evolution equation for the population distribution. With this contribution, we provide a platform for understanding under what environmental, ecological, and evolutionary conditions ecosystems evolve toward being more or less modular. A major contribution of this work is that we are able to decompose the overall driver of changes at the macro level (such as interconnectedness) into three components: (i) ecologically driven change, (ii) evolutionarily driven change, and (iii) environmentally driven change.


Assuntos
Evolução Biológica , Ecologia/métodos , Dinâmica Populacional/estatística & dados numéricos , Biodiversidade , Ecossistema , Meio Ambiente , Modelos Teóricos , Fenótipo , Seleção Genética/fisiologia
17.
J Wildl Dis ; 54(1): 175-179, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29048263

RESUMO

: We captured 14 individual African wolves ( Canis lupaster) a total of 16 times in the Ethiopian Highlands in April 2015 and March 2016 by using rubber-lined foothold traps and immobilized them with dexmedetomidine-ketamine. Traps were baited with sheep meat and surveyed every 2 h. Capture efficiency (number of captures per number of visits) was 0.94, and capture rate (number of captures per number of trap nights) was 0.24. Trapped wolves were immobilized with 0.025 mg/kg dexmedetomidine and 8-10 mg/kg ketamine on the basis of respective estimated body mass. Mean (SD) induction times were 3.4 (0.5) min for subadults ( n=4), 3.5 (0.3) min for adult males ( n=4), and 4.7 (1.0) min for adult females ( n=6). Inductions were calm, muscle relaxation was good, and all animals were completely immobilized. Apart from increased rectal temperatures, no major negative side effects were observed. Atipamezole at 10 mg intramuscularly per milligram of dexmedetomidine administered was used for reversal at a mean of 43.5 (7.7) min after administration of dexmedetomidine-ketamine. Recoveries were relatively smooth, and animals were on feet, leaving the site within a mean of 13.6 (3.9) min, after atipamezole administration. Our results indicate that African wolves can be safely captured and immobilized by using rubber-lined foothold traps and dexmedetomidine and ketamine.


Assuntos
Dexmedetomidina/farmacologia , Ketamina/farmacologia , Restrição Física/veterinária , Lobos , Antagonistas de Receptores Adrenérgicos alfa 2/farmacologia , Animais , Animais Selvagens , Dexmedetomidina/administração & dosagem , Etiópia , Feminino , Imidazóis/farmacologia , Ketamina/administração & dosagem , Masculino
18.
Proc Natl Acad Sci U S A ; 114(49): 12970-12975, 2017 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-29109246

RESUMO

A wide range of climate change-induced effects have been implicated in the prevalence of infectious diseases. Disentangling causes and consequences, however, remains particularly challenging at historical time scales, for which the quality and quantity of most of the available natural proxy archives and written documentary sources often decline. Here, we reconstruct the spatiotemporal occurrence patterns of human epidemics for large parts of China and most of the last two millennia. Cold and dry climate conditions indirectly increased the prevalence of epidemics through the influences of locusts and famines. Our results further reveal that low-frequency, long-term temperature trends mainly contributed to negative associations with epidemics, while positive associations of epidemics with droughts, floods, locusts, and famines mainly coincided with both higher and lower frequency temperature variations. Nevertheless, unstable relationships between human epidemics and temperature changes were observed on relatively smaller time scales. Our study suggests that an intertwined, direct, and indirect array of biological, ecological, and societal responses to different aspects of past climatic changes strongly depended on the frequency domain and study period chosen.


Assuntos
Doenças Transmissíveis/epidemiologia , Epidemias/história , China/epidemiologia , Mudança Climática , Doenças Transmissíveis/história , Desastres/história , História Antiga , História Medieval , Humanos , Prevalência
19.
Nature ; 552(7683): 92-95, 2017 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-29186124

RESUMO

In the fossil record, taxa exhibit a regular pattern of waxing and waning of occupancy, range or diversity between their origin and extinction. This pattern appears to contradict the law of constant extinction, which states that the probability of extinction in a given taxon is independent of that taxon's age. It is nevertheless well established for species, genera and higher taxa of terrestrial mammals, marine invertebrates, marine microorganisms, and recent Hawaiian clades of animals and plants. Here we show that the apparent contradiction between a stochastically constant extinction rate and the seemingly deterministic waxing and waning pattern of taxa disappears when we consider their peak of expansion rather than their final extinction. To a first approximation, we find that biotic drivers of evolution pertain mainly to the peak of taxon expansion, whereas abiotic drivers mainly apply to taxon extinction. The Red Queen's hypothesis, which emphasizes biotic interactions, was originally proposed as an explanation of the law of constant extinction. Much effort has since been devoted to determining how this hypothesis, emphasizing competition for resources, relates to the effects of environmental change. One proposed resolution is that biotic and abiotic processes operate at different scales. By focusing attention on taxon expansion rather than survival, we resolve an apparent contradiction between the seemingly deterministic waxing and waning patterns over time and the randomness of extinction that the Red Queen's hypothesis implies.


Assuntos
Evolução Biológica , Extinção Biológica , Modelos Biológicos , Filogenia , Animais , Organismos Aquáticos/classificação , Comportamento Competitivo , Meio Ambiente , Fósseis , Hawaii , Mamíferos/classificação , Plantas/classificação , Densidade Demográfica , Probabilidade , Processos Estocásticos
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