Synchronization Of Life Cycles Research Articles

Predictable local adaptation in butterfly photoperiodism but not thermal performance along a latitudinal cline

AbstractIn seasonal environments, organisms must synchronize their life cycles to conditions favorable for growth and reproduction. Because season length varies geographically, local adaptation should arise in traits that regulate phenological responses. Geographic photoperiodism clines are well known, but comparable studies on thermal performance are equivocal and often overlook nonlinear responses. Therefore, we examined local adaptation in plastic responses to both photoperiod and temperature along a 752‐km latitudinal cline, by comparing four Swedish populations of the butterfly Pieris napi. Using a common garden design, we estimated (1) photoperiod response curves for diapause induction and (2) thermal performance curves for development and growth rates. We show that differences in photoperiodism follow the expected geographical pattern, where diapause is induced at longer daylengths in northern populations (where growth seasons are short and summer days long). However, population differences in thermal performance curves were small and seemingly idiosyncratic, without clear clinal patterns. Photoperiodic responses appear to evolve more readily than thermal responses, highlighting photoperiodism as a key driver of local life cycle synchronization.

To sleep or not to sleep: Dormancy and life history traits in Eucypris virens (Crustacea, Ostracoda).

Dormancy represents an investment with its own costs and benefit. Besides the advantage obtained from the avoidance of harsh environments and from the synchronization of life cycles with seasonal changes, an organism could benefit from a temporary stop in growth and reproduction. To test this hypothesis a transgenerational experiment was carried out comparing the life history traits of clonal females of Eucypris virens from resting and non-resting eggs at two different photoperiods: short day length (6:18 L:D), proxy of favorable but unpredictable late winter-spring hydroperiod, and long day length (16:8 L:D) proxy of dry predictable unfavorable season, inducing resting egg production and within-generation plasticity (WGP). Clonal females that were dormancy deprived showed the highest age at first deposition and the lowest fecundity. Dormancy seems to work as a resetting mechanism of reproduction. Transgenerational plasticity (TGP) had a bounce back pattern: the phenotype of F1 generation was influenced by cues experienced in the F0 generation but the effects of F0 exposure were not evident in the F2. TGP might be adaptive when a mother experiences some kind of seasonality or stochasticity producing both resting and nonresting eggs. A positive relationship between the number of resting eggs and the total number of eggs per females suggested the absence of trade-off between dormancy and reproduction. Both WGP and TGP increase the mother long term fitness with important consequences on population dynamics, on the way a species spread throughout space and time and might respond to climate change.

Service Relationship Orchestration: Lessons Learned From Running Large Scale Smart City Platforms on Kubernetes

Smart cities aim to make urban life more enjoyable and sustainable but their highly heterogeneous and distributed context creates unique operational challenges. In such an environment, multiple companies work together with government on applications and data streams spanning several management domains. Deploying these applications, each of which consists of several connected services, and maintaining an overview of application topologies remains difficult. Even though cloud modelling languages have been proposed to solve similar issues, they are not well fit for such a heterogeneous environment because they often require an “all or nothing” approach. Moreover, cloud modelling languages add an additional abstraction layer that rarely supports all features of the underlying platform and make it harder to reuse existing knowledge and tools. This research defines service relationships as the key element to modelling applications as topologies of services. We use this definition to pinpoint what is lacking in the state of the art Kubernetes orchestration tools and provide a blueprint for how relationship support can be added to any orchestrator. We present “orcon”, a proof of concept orchestrator that extends the Kubernetes API to allow managing relationships between services by adding metadata to service definitions. Our evaluation shows this orchestrator enables lifecycle synchronization and configuration change propagation with an overhead of only 0.44 seconds per service.

Synchronization of life cycles by collective transport and emergence of supercycles.

A model of physiological age, accompanied by nonlinear diffusion in space, is studied analytically and numerically, and is shown to develop nonstationary traveling population waves. A window of intermediate growth rates is found where collective supercycles are formed from individual (stochastic) life cycles. Supercycle periods can be considerably different (larger or smaller) than the average longevities of contributing individuals, while the time-averaged spatial expansion rate has a local maximum in the supercycling mode. A method of adiabatic similarity solutions is used to derive dependencies of the solution parameters on source and sink inhomogeneities, and obtain closed coupled dynamic equations for the age structure and leading and trailing fronts. Analytical results are compared with numerically computed similarity and full solutions for several types of population waves. We discuss possible model applications to development of lichen thallus, multiyear patterns of agricultural crop yields, and autocorrelation of locust swarming.

Analysis of the phoretic relationships between mites of the genus Trichouropoda Berlese (Parasitiformes: Uropodina) and the longhorn beetle Plagionotus detritus (Linnaeus) (Coleoptera: Cerambycidae) based on multiannual observations in Białowieża Primeval Forest, Central Europe

ABSTRACTWe studied the phoretic relationships between the mites of the genus Trichouropoda Berlese, 1916 (Uropodina) and the longhorn beetle Plagionotus detritus (Linnaeus, 1758) based on large samples of specimens (2050 beetles and 19,216 mites) collected in the Białowieża Primeval Forest in Central Europe. Phoresy was studied over the years 2014, 2015, and 2016, with the emphasis on multi-annual trends in host–phoront associations, seasonal changes in intensity of phoresy, proportion of carriers of mites in the beetle population, and preferences of phoretic deutonymphs for specific parts of the host’s body. The high repeatability in all the variables we studied indicates high stability of the phoretic relationships, probably resulting from the synchronization of life cycles of beetle dispersants and phoretic mites. The long-term coevolution of phoronts and carriers in a natural forest ecosystem, as well as the expected close association of mites with specific beetle-generated microhabitats in larval galleries, may be important factors affecting the strength of the phoretic relationship.

Correction: Obligate development of Blastocrithidia papi (Trypanosomatidae) in the Malpighian tubules of Pyrrhocoris apterus (Hemiptera) and coordination of host-parasite life cycles.

[This corrects the article DOI: 10.1371/journal.pone.0204467.].

Obligate development of Blastocrithidia papi (Trypanosomatidae) in the Malpighian tubules of Pyrrhocoris apterus (Hemiptera) and coordination of host-parasite life cycles.

Blastocrithidia papi is a unique trypanosomatid in that its life cycle is synchronized with that of its host, and includes an obligate stage of development in Malpighian tubules (MTs). This occurs in firebugs, which exited the winter diapause. In the short period, preceding the mating of overwintered insects, the flagellates penetrate MTs of the host, multiply attached to the epithelial surface with their flagella, and start forming cyst-like amastigotes (CLAs) in large agglomerates. By the moment of oviposition, a large number of CLAs are already available in the rectum. They are discharged on the eggs' surface with feces, used for transmission of bugs' symbiotic bacteria, which are compulsorily engulfed by the newly hatched nymphs along with the CLAs. The obligate development of B. papi in MTs is definitely linked to the life cycle synchronization. The absence of peristalsis allow the trypanosomatids to accumulate and form dense CLA-forming subpopulations, whereas the lack of peritrophic structures facilitates the extensive discharge of CLAs directly into the hindgut lumen. The massive release of CLAs associated with oviposition is indispensable for maximization of the infection efficiency at the most favorable time point.

Life cycle synchronization is a viral drug resistance mechanism.

Viral infections are one of the major causes of death worldwide, with HIV infection alone resulting in over 1.2 million casualties per year. Antiviral drugs are now being administered for a variety of viral infections, including HIV, hepatitis B and C, and influenza. These therapies target a specific phase of the virus’s life cycle, yet their ultimate success depends on a variety of factors, such as adherence to a prescribed regimen and the emergence of viral drug resistance. The epidemiology and evolution of drug resistance have been extensively characterized, and it is generally assumed that drug resistance arises from mutations that alter the virus’s susceptibility to the direct action of the drug. In this paper, we consider the possibility that a virus population can evolve towards synchronizing its life cycle with the pattern of drug therapy. The periodicity of the drug treatment could then allow for a virus strain whose life cycle length is a multiple of the dosing interval to replicate only when the concentration of the drug is lowest. This process, referred to as “drug tolerance by synchronization”, could allow the virus population to maximize its overall fitness without having to alter drug binding or complete its life cycle in the drug’s presence. We use mathematical models and stochastic simulations to show that life cycle synchronization can indeed be a mechanism of viral drug tolerance. We show that this effect is more likely to occur when the variability in both viral life cycle and drug dose timing are low. More generally, we find that in the presence of periodic drug levels, time-averaged calculations of viral fitness do not accurately predict drug levels needed to eradicate infection, even if there is no synchronization. We derive an analytical expression for viral fitness that is sufficient to explain the drug-pattern-dependent survival of strains with any life cycle length. We discuss the implications of these findings for clinically relevant antiviral strategies.

Evolutionary responses of aquatic macroinvertebrates to two contrasting flow regimes

Natural disturbances are agents of natural selection that drive multiple biological adaptations along evolutionary time. Frequent, high magnitude disturbances are expected to select for morphological and behavioral traits to resist or to avoid them. In contrast, predictable and seasonal disturbances are expected to select for synchronized life cycles to avoid unfavorable periods. We assessed the effect of flood disturbances on aquatic macroinvertebrates in two rivers with contrasting flow regimes: the Gila (USA) with seasonal floods and droughts, and the Thur (Switzerland) with a high frequency of aseasonal floods. Macroinvertebrates were analyzed based on 46 biological trait categories classified into morphological, life-cycle synchronization, and behavioral strategies. Flood effects on diversity and composition were much clearer for the Gila than for the Thur. Overall, biological adaptations were related to the flood regime of each river. Morphological adaptations to resist or avoid floods prevailed under frequent and aseasonal disturbances (the Thur), whereas life-cycle synchronization and behavioral adaptations were associated with highly seasonal, predictable, and low-frequency disturbances (the Gila). Given that forecasted future flow regimes differ between regions, our results suggest that the effects of future flow regime alterations will ultimately depend on the adaptation strategies to current flow regimes.

Life cycle size dynamics in Didymosphenia geminata (Bacillariophyceae).

Didymosphenia geminata has received a great deal of attention in the last 25years, and considerable effort has gone into determining the origin, ecological impact, and economic consequences of its invasive behavior. While environmental conditions are a controlling influence in distribution, the extreme success of the species may be tied to its basic biology and life history. Little is known, however, about population dynamics, size restoration and reproduction of D.geminata. The objective of this study was to determine the temporal patterns in cell size frequency, size restoration strategy, and synchronization of life cycles between populations in close proximity. We implemented FlowCam technology to measure the length of more than 100,000 D.geminata cells from two sites in South Boulder Creek, Colorado over 1year. We applied finite mixture modeling to uncover temporal patterns in size distribution. Our results show that collections of D.geminata exhibited a complex, multimodal size distribution, almost always containing four overlapping age cohorts. We failed to observe direct visual evidence of the sexual phase. Multiple abrupt and directional shifts in size distribution, however, were documented providing conclusive evidence of cell size restoration. Lastly, nodules in close proximity were asynchronous with respect to size frequency profiles and size diminution, highlighting the relevance of spatial heterogeneity in in situ diatom size dynamics. This study is the first to document the complexity of diatom cell size distribution in a lotic system, size restoration in D.geminata, and the variability in rates of size reduction at microhabitat spatial scales.

Post-polyploidisation morphotype diversification associates with gene copy number variation

Genetic models for polyploid crop adaptation provide important information relevant for future breeding prospects. A well-suited model is Brassica napus, a recent allopolyploid closely related to Arabidopsis thaliana. Flowering time is a major adaptation trait determining life cycle synchronization with the environment. Here we unravel natural genetic variation in B. napus flowering time regulators and investigate associations with evolutionary diversification into different life cycle morphotypes. Deep sequencing of 35 flowering regulators was performed in 280 diverse B. napus genotypes. High sequencing depth enabled high-quality calling of single-nucleotide polymorphisms (SNPs), insertion-deletions (InDels) and copy number variants (CNVs). By combining these data with genotyping data from the Brassica 60 K Illumina® Infinium SNP array, we performed a genome-wide marker distribution analysis across the 4 ecogeographical morphotypes. Twelve haplotypes, including Bna.FLC.A10, Bna.VIN3.A02 and the Bna.FT promoter on C02_random, were diagnostic for the diversification of winter and spring types. The subspecies split between oilseed/kale (B. napus ssp. napus) and swedes/rutabagas (B. napus ssp. napobrassica) was defined by 13 haplotypes, including genomic rearrangements encompassing copies of Bna.FLC, Bna.PHYA and Bna.GA3ox1. De novo variation in copies of important flowering-time genes in B. napus arose during allopolyploidisation, enabling sub-functionalisation that allowed different morphotypes to appropriately fine-tune their lifecycle.

The evolutionary ecology of interactive synchronism: the illusion of the optimal phenotype

AbstractIn this article, we discuss some ecological-evolutionary strategies that allow synchronization of organisms, resources, and conditions. Survival and reproduction require synchronization of life cycles of organisms with favourable environmental and ecological features and conditions. This interactive synchronization can occur directly, through pairwise or diffuse co-evolution, or indirectly, for example, as a result of actions of ecosystem engineers and facilitator species. Observations of specific interactions, especially those which have coevolved, may give the false impression that evolution results in optimal genotypes or phenotypes. However, some phenotypes may arise under evolutionary constraints, such as simultaneous evolution of multiple traits, lack of a chain of fit transitional forms leading to an optimal phenotype, or by limits inherent in the process of selection, set by the number of selective deaths and by interference between linked variants. Although there are no optimal phenotypes, optimization models applied to particular species may be useful for a better understanding of the nature of adaptations. The evolution of adaptive strategies results in variable life histories. These strategies can minimize adverse impacts on the fitness of extreme or severe environmental conditions on survival and reproduction, and may include reproductive strategies such as semelparity and iteroparity, or morphological, physiological, or behavioural traits such as diapause, seasonal polyphenism, migration, or bet-hedging. However, natural selection cannot indefinitely maintain intra-population variation, and lack of variation can ultimately extinguish populations.

Reproductive Requirements and Life Cycle of Iberorhyzobius rondensis (Coleoptera: Coccinellidae), Potential Biological Control Agent of Matsucoccus feytaudi (Hemiptera: Matsucoccidae).

Several pine bast scales (Hemiptera: Matsucoccidae) are important pests of pine trees in the Northern Hemisphere. Some species are invasive and cause significant economic and environmental impacts. Such is the case with Matsucoccus feytaudi Ducasse, an invasive pest of maritime pine forests in Southeastern France, Italy, and Corsica. The ladybird Iberorhyzobius rondensis (Eizaguirre) is a recently described species that is endemic to the Iberian Peninsula and is a potential candidate for the biological control of M. feytaudi. However, little is known of the biology of I. rondensis. As part of the risk assessment study for a classical biological control program, the phenology and reproductive mechanisms of the beetle were analyzed. I. rondensis is univoltine and is seasonally synchronized with the phenology of the prey M. feytaudi, which is also univoltine. An obligatory reproductive diapause of 5-6 mo and the need to feed on the eggs of the prey to begin oviposition emerged as the two primary mechanisms that assure life cycle synchronization of the ladybird with its prey. Female fecundity was also higher when the ladybirds were fed M. feytaudi eggs. Life cycle synchronization with M. feytaudi and reproduction triggered by consumption of prey eggs indicate that I. rondensis is a promising biological control agent of the pine bast scale.

Mismatch between birth date and vegetation phenology slows the demography of roe deer.

Author SummaryClimate change can alter the synchronization of life cycles between organisms at different points in the food chain. If species do not respond to climate change, the timing of peak resource availability may fail to match the timing of peak energy expenditure. Many bird species have been able to advance their laying date to match a change in the timing of caterpillar abundance. Herbivores are similarly expected to track changes in the timing of vegetation growth. In this study, we combine statistical analysis with demographic modeling to analyze the influence of a climate-driven shift in the timing of the spring vegetation flush on the birth date and demography of roe deer. In recent years, climate change has generated a marked increase in local temperatures and a progressively earlier vegetation flush. Despite these changes, we observed no shift in timing of the birth date of roe deer over the 27-year study period. This failure to track environmental change resulted in a mismatch between vegetation flush and birth date, which in turn caused a decrease in survival of the young, and hence a reduction in roe deer fitness. Birth date was under strong directional selection, but was not strongly heritable, suggesting that any evolutionary response of birth date to climate change might be limited. We suggest that a plastic response in birth date did not occur because reproduction is triggered by day length rather than resource availability in roe deer.

Assessment of Risks in Automobile Remanufacturing

With the advent of recycling economy era, the automobile remanufacturing industry has aroused wide concern of the society. This paper first proposes a risk map in automobile remanufacturing, including technology risks, market risks, management risks, cost risks, parts supply risks and life cycle synchronization risks. Then, it designs an assessment indicator system of risks in automobile remanufacturing and uses AHP approach to establish a model to assess risks in automobile remanufacturing. Finally, the paper calculation example and proves its correctness and practicality in the empirical analysis section.

Months of Asynchrony in Offspring Production but Synchronous Adult Emergence: The Role of Diapause in an Ectoparasite's Life Cycle

Off-host stages of temperate zone ectoparasites must overcome two challenges: coping with unfavorable seasons and synchronizing their life cycles with host availability. In general, little is known about the seasonal cycles of insect ectoparasites of warm-blooded animals. The current study investigates the unusual phenology of a viviparous hippoboscid fly, the deer ked (Lipoptena cervi L.), that parasitizes boreal cervids. Despite months of asynchrony in offspring production, the adults emerge synchronously in mid-August across the northern boreal zone. We examined the role of diapause variation in the synchronization of life cycles by testing adult emergence success and time in relation to offspring birth month (October to April) and with respect to chilling time and photoperiod. Unexpectedly, we found that photoperiod had no role in regulating the life cycle, but diapause was maintained as long as pupae were exposed to cold. Pupae born before February needed a slightly longer exposure to high temperatures to terminate diapause if the cold period was short. Despite the apparent importance of a long period of chilling for life cycle synchrony, it was not required to terminate diapause. This finding of cold mainly preventing, rather than promoting, diapause termination is not novel among temperate insects, but it is rare. Slow diapause termination as a response to exceptionally long exposure to high, not low, temperatures seems to be a cornerstone for synchronizing the life cycle in the deer ked.

Independent divergence of 13- and 17-y life cycles among three periodical cicada lineages

The evolution of 13- and 17-y periodical cicadas (Magicicada) is enigmatic because at any given location, up to three distinct species groups (Decim, Cassini, Decula) with synchronized life cycles are involved. Each species group is divided into one 13- and one 17-y species with the exception of the Decim group, which contains two 13-y species-13-y species are Magicicada tredecim, Magicicada neotredecim, Magicicada tredecassini, and Magicicada tredecula; and 17-y species are Magicicada septendecim, Magicicada cassini, and Magicicada septendecula. Here we show that the divergence leading to the present 13- and 17-y populations differs considerably among the species groups despite the fact that each group exhibits strikingly similar phylogeographic patterning. The earliest divergence of extant lineages occurred ∼4 Mya with one branch forming the Decim species group and the other subsequently splitting 2.5 Mya to form the Cassini and Decula species groups. The earliest split of extant lineages into 13- and 17-y life cycles occurred in the Decim lineage 0.5 Mya. All three species groups experienced at least one episode of life cycle divergence since the last glacial maximum. We hypothesize that despite independent origins, the three species groups achieved their current overlapping distributions because life-cycle synchronization of invading congeners to a dominant resident population enabled escape from predation and population persistence. The repeated life-cycle divergences supported by our data suggest the presence of a common genetic basis for the two life cycles in the three species groups.

A diffusion-induced transition in the phase separation of binary fluid mixtures subjected to a temperature ramp

Demixing of binary fluids under slow temperature ramps shows repeated waves of nucleation which arise as a consequence of the competition between generation of supersaturation by the temperature ramp and relaxation of supersaturation by diffusive transport and flow. Here, we use an advection-reaction-diffusion model to study the oscillations in the weak- and strong-diffusion regime. There is a sharp transition between the two regimes, which can only be understood based on the spatial distribution of the composition, rather than in terms of the average composition. Our results shed light on the parameter drift and secondary features observed in phase separating fluids subjected to a temperature ramp, and they bear intriguing communalities with macroscopic oscillations due to synchronization of life cycles in ageing populations.

Rapid seasonal adaptation of an alien bruchid after introduction: geographic variation in life cycle synchronization and critical photoperiod for diapause induction

Whether alien insects that are introduced into temperate regions adapt to seasonally changing environmental conditions is an important question in evolutionary biology. If rapid evolution has occurred in a non-native environment, a latitudinal cline in critical photoperiod for diapause induction (i.e., the photoperiod at which half of the individuals enter diapause) and in life cycle synchronization with host plant phenology should be evident among locations. The alien bruchid Acanthoscelides pallidipennis (Motschulsky) (Coleoptera: Bruchidae) is native to North America and introduced into Japan with the host plant Amorpha fruticosa L. (Fabaceae) in the late 1940s. To examine whether seasonal adaptation has occurred in A. pallidipennis, we conducted a laboratory experiment and phenological observations using three latitudinally different populations. We bred F1 eggs at 22 °C and five photoperiodic regimens – L:D = 10:14, 13:11, 14:10, 15:9, or 16:8 hours – and examined whether diapause was induced. The estimated critical photoperiod for diapause induction was longest in the most northern population and shortest in the most southern population. Life cycle was found to be synchronized with host phenology in each location. Also voltinism varied geographically, from univoltine in the northern population to bivoltine in the southern populations. These results showed that A. pallidipennis rapidly adapted to seasonal environmental conditions in Japan after its introduction.

Life cycle and sexual mode adaptations of the parasitic mite Ensliniella parasitica (Acari: Winterschmidtiidae) to its host, the eumenine wasp Allodynerus delphinalis (Hymenoptera: Vespidae)

We investigated two important life-history traits in parasites, i.e., life cycle and reproductive mode, that should be adapted to specific hosts using the parasitic mite Ensliniella parasitica Vitzthum, 1925 and the host wasp Allodynerus delphinalis (Giraud, 1866) in field- and laboratory-reared nests. The life cycle of E. parasitica was synchronized with that of the wasp; this synchronization facilitated dispersal. Life-cycle plasticity of the mite was low and development was halted on dead hosts. There was no significant difference in wasp juvenile mortality between mite-laden and mite-free individuals under controlled conditions. Therefore, the mites were suggested to be not toxic to the hosts. We confirmed for the first time that virgin female mites ovoviviparously produce arrhenotokous males the size of a protonymph to compensate for the absence of males in a cell. Although no obvious antagonistic behaviour between large (i.e., sexual) and small males was observed, large males mounted females on late prepupal hosts, about 1–2 days before either the egg or the small male was laid. We conclude that the adaptations of the mite to its host involve life-cycle synchronization, low-impact parasitism, and facultative parthenogenesis.