Two questions in the research of animal personality—whether there is a correlation between a personality trait and individual reproductive success,and what is the genetic basis underlying a personality trait—remain ...Two questions in the research of animal personality—whether there is a correlation between a personality trait and individual reproductive success,and what is the genetic basis underlying a personality trait—remain unresolved.We addressed these two questions in three shrub-nesting birds,the Azure-winged Magpie(Cyanopica cyanus,AM),White-collared Blackbird(Turdus albocinctus,WB),and Brown-cheeked Laughingthrush(Trochalopteron henrici,BL).The personality type of an individual was first identified according to its response to a territorial intruder.Then,we compared the fleeing distance,breeding parameters,and differential expressed genes(DEGs) in the brain transcriptome between bold and shy breeders.In the three species,bold breeders exhibited more aggressiveness towards an intruder of their territory than did shy breeders.The reproductive success of bold breeders was significantly higher than that of shy breeders in AM but not in WB and BL.The three species shared one DEG,crabp1,which was up-regulated in bold relative to in shy individuals.By regulating the expression of corticotropin-releasing hormone,higher crabp1 gene expression can decrease cellular response to retinoic acid.Therefore,bold individuals are insensitive to external stresses and able to exhibit more aggressiveness to intruders than their shier counterparts.Aggressiveness is beneficial to bold individuals in AM but not in WB and BL because the former could evoke neighbors to make the same response of defending against intruders but the latter could not.Although a personality trait may have the same genetic basis across species,its correlation with reproductive success depends largely on the life history style of a species.展开更多
As the largest genus of Halymeniaceae,Grateloupia has been widely reported.Here,we observed the life history and early development of Grateloupia constricata Li et Ding and investigated the effects of temperature,irra...As the largest genus of Halymeniaceae,Grateloupia has been widely reported.Here,we observed the life history and early development of Grateloupia constricata Li et Ding and investigated the effects of temperature,irradiance,and photoperiod on the discoid crust and sporeling development of G.constricata under laboratory conditions.We observed that the type of carpospore development was“mediate discal type”.The life history included homotypic gametophyte(haploid),carposporophyte(diploid),and tetrasporophyte(diploid),with typical isomorphic alternation of generations.The results of double factorial analysis showed that both single factorial effects and interaction among temperature,photoperiod,and irradiance were obviously significant on the discoid crust and sporeling development.Furthermore,we found that the optimum combination of condition for the early growth and development of G.constricata was temperature 20°C,irradiance 80μmol photons/(m^2·s)and photoperiod 16L:8D.This study provides the theoretical basis and technical support for the conservation of the Grateloupia germplasm,artificial breeding,large-scale cultivation and sustainable development.展开更多
Background:Black soldier fly(BSF)is one of the most promising species for the intensive breeding of insects given its adaptability and its efficiency in the conversion of waste.To maximize the production and use waste...Background:Black soldier fly(BSF)is one of the most promising species for the intensive breeding of insects given its adaptability and its efficiency in the conversion of waste.To maximize the production and use waste as substrates,it is essential to determine the larvae nutritional requirements.The study aims to evaluate the effects of5 practical,semi-purified and isoenergetic diets(PSPID)with increasing protein levels(10%,CP10;14%,CP14;16%,CP16;19%,CP19)on BSF life history traits.A total of 2000 six-day-old larvae were weighed and divided into groups of 100(4 replicates/treatment[PSPID and Gainesville diet(GA)used as environmental control]).In larva-prepupa stage,sampling was carried out on 30 individuals/replicate,while in prepupa-adult stage on 35.Results:In the whole larval stage,the CP16 treatment performed better when compared to the other groups.At18 days old,the CP14 treatment showed a higher weight than the CP19(P<0.01),while the CP10 and CP16weights were intermediate.On the contrary,the CP10 prepupae weight was higher than the CP19(P<0.01).The CP10 and CP14 pupae performed better in terms of weight when compared to the others(P<0.01).The dietary treatments did not affect the adult parameters.The sex significantly influenced both the exuvia weight,which was the greatest in females(P<0.001),and the fly lifespan,longest in males(P<0.05).Fly lifespan was also influenced by the interaction between treatment and sex,with the CP19 females showing a longer life than the others(P<0.05).Conclusions:In conclusion,the optimal protein level considering the whole larval stage is 16%on dry matter(DM).At 18 days old,looking at the size intended for the meal production,it can be considered 14%on DM.The result obtained on adult emergence in PSPID may not be attributable to the protein content.Further researches on macronutrients requirements determination have to be conducted to evaluate the substrates composition effects on BSF life history traits.展开更多
The complex life histories of demersal fishes are artificially separated into multiple stages along with changes in morphology and habitat.It is worth exploring whether the phenotypes expressed earlier and later durin...The complex life histories of demersal fishes are artificially separated into multiple stages along with changes in morphology and habitat.It is worth exploring whether the phenotypes expressed earlier and later during the life cycle are related or decoupled.The life stages of first year Pacific cod(Gadus macrocephalus)were tracked over different hatch years and regions to test whether the early life history had a long-lasting effect on subsequent growth.We further explored the contribution of growth in the early and subsequent life history stages to body size at the end of each stage.In addition to the accessory growth centre and the first annual ring,the other two checks on the otolith possibly related to settlement and entering deeper waters were identified in 75 Pacific cod individuals.The direct and indirect relationships among the life history stages was interpreted based on path analysis.The results showed that growth prior to the formation of the accessory growth centre had a significant effect on the absolute growth of the fish before and after settlement and migration to deep water.However,there was no or moderate evidence that early growth affected the body size at each stage,which was mainly regulated by growth during the stage.This study supports the lasting effect of early growth and clarifies that it affects size mainly by indirectly regulating staged growth.Quantifying the phenotype relationships and identifying the internal mechanisms form the basis for assessing population dynamics and understanding the processes behind the changes.展开更多
Dogtooth tuna,Gymnosarda unicolor were sampled off the east coast of Australia(southwest Pacific Ocean)from 2007 to 2012.Ages were determined by examining thin transverse sections of their sagittal otoliths and were b...Dogtooth tuna,Gymnosarda unicolor were sampled off the east coast of Australia(southwest Pacific Ocean)from 2007 to 2012.Ages were determined by examining thin transverse sections of their sagittal otoliths and were based on counts of alternating opaque and translucent zones(annual growth increments).Growth was rapid during the first year of life,after which growth in length was much reduced.Parameters of the constrained von Bertalanffy growth function(fork length-at-age)were L∞=1164.77(mm,FL)and K=0.44 year^(-1).Preliminary estimates of longevity indicate a maximum observed age of at least 20 years.There was a high degree of variation in the observed length and age of sexual maturity for G.unicolor.Despite this variation,the size at 50%maturity for female G.unicolor estimated in this study was 713 mm FL(<2 years of age).The diet of G.unicolor is very broad and covers a range of fish species.The life history characteristics of G.unicolor overall,indicate that this species may be somewhat resilient to fishing.However,reports of localised depletions,in association with heavy targeting by sports fishers,low effective population sizes and patchy recruitment indicate that this species is particularly vulnerable to overfishing.展开更多
There are no eternal individual lives so life continues by relaying with reproduction.Consequently,lifespan and fecundity are two essential genetic traits of life.The life history tradeoffs theory holds that there is ...There are no eternal individual lives so life continues by relaying with reproduction.Consequently,lifespan and fecundity are two essential genetic traits of life.The life history tradeoffs theory holds that there is an inverse relationship between lifespan and fecundity.This paper proposes two new concepts,i.e.,“lifespan of pathogens”and treatment of infections by“antibiogenesis”.The lifespan of pathogens is the time limitation of those tiny lives just as other large creatures.Notably,the lifespan of bacterium is the time interval from the cell division by which it is produced to next division by then its life ends and transforms to two new lives,or dies.Antibiogenesis means inhibiting generation of new lives.By the principle of life history tradeoffs,the lifespan of pathogens determines the speed of their proliferations and consequently the modality of infection.The treatment principle of antibiogenesis requires the duration of treatment to be determined by the lifespan of infected pathogens.The life history tradeoffs theory and the two concepts are helpful to understanding the pathobiology and shaping the clinical aspects of infectious diseases.展开更多
Understanding life history patterns,individual fitness and population fitness can assist with conservation of endangered species.Field data on life history traits(i.e.age specific fecundity,age specific mortality,age ...Understanding life history patterns,individual fitness and population fitness can assist with conservation of endangered species.Field data on life history traits(i.e.age specific fecundity,age specific mortality,age at first reproduction,litter size and adult life expectancy)were collected from 121 Hainan Eld’s deer(Cervus eldi hainanus Thomas,1918),an in situ herd of an endemic,rare and endangered cervid inhabiting Bangxi Natural Reserve of Hainan Island,from 1990 to 2002.First,we constructed a dynamic life table to analyze the life history pattern of the population,which showed that the difference between the average lifespan of males and females was not significant(P>0.05),and that the difference between the average lifespan of the whole Hainan Eld’s deer population and that of other Eld’s deer populations living in South Asia(P>0.05),North America(P>0.05)and Europe(P>0.05)was not significant.Second,we used individual reproductive success or number of offspring of a male over its lifetime to estimate male individual fitness.Statistic analysis showed that male individual fitness was not significantly correlated with total antler velvet mass.Third,we used the population intrinsic rate of increase to measure population fitness,and population fitness of Hainan Eld’s deer was compared with similar indexes of 5 other cervid species.Hainan Eld’s deer population fitness index was 0.012,the second lowest value relative to other cervids.Results indicated that this rare species is still endangered and is in need of additional protection.展开更多
Background: In temperate-breeding birds, individuals must adjust their physiological states from one life-history stage to another in response to changing conditions to maximize ecological fitness. Previous evidences ...Background: In temperate-breeding birds, individuals must adjust their physiological states from one life-history stage to another in response to changing conditions to maximize ecological fitness. Previous evidences have shown that body mass, size-corrected mass(SCM), and hematocrit(Hct) could be used as estimates of the energetic state of individuals to illustrate life-history trade-offs and individual quality in field physiology. Plasma alkaline phosphatase(ALP) plays critical roles in regulating the metabolism of energy but very limited information is known on its link with body mass or Hct.Methods: We determined the changes of plasma ALP levels in both early breeding and wintering stages of male Eurasian Tree Sparrows(Passer montanus), and examined the relationships between ALP and body mass, SCM, and Hct of the birds.Results: Our study showed that(1) in male Eurasian Tree Sparrows, body mass did not vary with life-history stage but plasma ALP activity significantly increased in the wintering stage compared to the breeding stage;(2) ALP activity was not correlated with individual body mass but was positively correlated with individual SCM and Hct. Such positive correlations, however, only occurred in the wintering but not in the breeding stages.Conclusions: Our results suggest that plasma ALP activities in free-living birds can be used as one of the indicators o body condition or nutritional status for analyzing individual variation in the wintering but not in the breeding stages. The life-history dependent relationships between plasma ALP activity and body condition may contribute to our better understanding of the trade-off between individual survival and reproduction in free-living animals.展开更多
Rickettsia consists of some of the most prevalent symbionts of insects and often plays a significant role in the biology of its hosts.Recently,a maternally inherited Torix group Rickettsia,provisionally named as RiTBt...Rickettsia consists of some of the most prevalent symbionts of insects and often plays a significant role in the biology of its hosts.Recently,a maternally inherited Torix group Rickettsia,provisionally named as RiTBt,was recorded in a species of notorious pest whitefly,tentatively named as Asia II 1,from the Bemisia tabaci complex.The role of this Rickettsia in the biology of its host is unknown.Here we investigated the impact of RiTBt on the performance and virus transmission capacity of Asia II 1.RiTBt did not significantly affect the life history parameters of the whitefly when the host insect was reared on tobacco,tomato,and cotton,three host plants with relatively low,medium and high suitability to the whitefly.Intriguingly,RiTBt slightly enhanced whitefly transmission of cotton leaf curl Multan virus(CLCuMuV),a virus that is transmitted by the whitefly in the field and has caused extensive damage to cotton production.Specifically,compared with whiteflies without RiTBt,following a 48 h virus acquisition whiteflies with RiTBt had higher titer of virus and showed higher efficiency of virus transmission.A rickettsial secretory protein BtR242 was identified as a putative virus-binding protein,and was observed to interact with the coat protein of CLCuMuV in vitro.Viral infection of the whitefly downregulated gene transcript levels of the BtR242 gene.These observations indicate that RiTBt has limited impact on the biology of the Asia II 1 whitefly,and whether this symbiont has functions in the biology of other host whiteflies warrants future investigation.展开更多
In this paper we review and integrate key aspects of behavioral and life history traits, food supply and populationdynamics of the white-footed mouse (Peromyscus leucopus), a species that is abundant and widely distri...In this paper we review and integrate key aspects of behavioral and life history traits, food supply and populationdynamics of the white-footed mouse (Peromyscus leucopus), a species that is abundant and widely distributedacross much of eastern North America. Results are based largely on a 33-year mark-and-recapture study in a forestfragment in northwest Ohio, USA. Behavioral plasticity in such reproductive traits as mating system and parentalcare allows this species to adjust quickly to changing environments. The species has a relatively “fast” life history,with rapid attainment of sexual maturity and high fecundity in the face of high mortality rates. Maximal reproductiveeffort early in life enables a rapid population response. Food supply, in the form of mast, determines thesize of the reproducing population in early spring, which, in turn, influences the size of the late summer peak population.The peak population size is also affected by short-term weather events possibly acting via the food supply.The effects of weather and food on population growth are in part mediated through competition, including defenseof space and suppression of reproduction. The inelasticity of female territories appears to set an upper limit topopulation density.展开更多
Recent research suggests that oxidative stress,via its links to metabolism and senescence,is a key mechanism linking life history traits such as fecundity and growth with survival;however,this has rarely been put unde...Recent research suggests that oxidative stress,via its links to metabolism and senescence,is a key mechanism linking life history traits such as fecundity and growth with survival;however,this has rarely been put under empirical scrutiny within free-living populations.Using a wild population of live-bearing skinks,we explored how plasma antioxidant activity(OXY),reactive oxidative metabolites(ROM),and the estimated oxidative stress index are associated with female and male life history.We found that male skinks have a significantly higher ROM and estimated oxidative stress index than female skinks,but this was not accompanied by a sex difference in mortality.Both sexes showed a non-linear association between OXY and age,indicating that the oldest and youngest individuals had the lowest OXY.Interestingly,female skinks with high OXY showed a decreased probability of survival to the following season.However,we found no significant associations between female reproductive investment(litter size or litter mass)or parturition date(i.e.metabolism)and oxidative status.Combined,our results offer mixed support for a role of oxidative stress in mediating life history traits and suggest that future studies need to explore oxidative stress during vitellogenesis in addition to using an intra-individual approach to understand the cost of reproduction and patterns of aging.展开更多
It has been demonstrated that phenotypic plasticity and genotype by envi-ronment interaction are important for coping with new and heterogeneous environments during invasions.Zaprionus indianus Gupta(Diptera:Drosophil...It has been demonstrated that phenotypic plasticity and genotype by envi-ronment interaction are important for coping with new and heterogeneous environments during invasions.Zaprionus indianus Gupta(Diptera:Drosophilidae)is an Afrotropical invasive fly species introduced to the South American continent in 1999.This species is generalist and polyphagous,since it develops and feeds in several different fruit species.These characteristics of Z.indianus suggest that phenotypic plasticity and genotype by environment interaction may be important in this species invasion process.In this sense,our aim was to investigate the role of genetic variation for phenotypic plasticity(geno-type by environment interaction)in Z.indianus invasion of the South American continent.Specifically,we quantified quantitative genetic variation and genotype by environment in-teractions of morphological and life history traits in different developmental environments,that is,host fruits.This was done in different populations in the invasive range of Z.indi-anus in Argentina.Results showed that Z.indianus populations have considerable amounts of quantitative genetic variation.Also,genotype by environment interactions was detected for the different traits analyzed in response to the different developmental environments.Interestingly,the amounts and patterns of these parameters differed between populations.We interpreled these results as the existence of diferences in evolutionary potential be-tween populations that have an important role in the short-and long-term success of the Z.indianus invasion process.展开更多
The fall armyworm(FAW),Spodoptera frugiperda,is a newly invasive,widespread agricultural pest in China.Understanding the suitability of the main field crops in Chinese agricultural system as host for this polyphagous ...The fall armyworm(FAW),Spodoptera frugiperda,is a newly invasive,widespread agricultural pest in China.Understanding the suitability of the main field crops in Chinese agricultural system as host for this polyphagous herbivore is especially important for making control strategy.Here,after FAWs were fed three important oil-bearing crops(oilseed rape,soybean and sunflower)planted in China and resultant population parameters were compared using the age-stage,two-sex life table method,survival of larvae on soybean was significantly lower than that on oilseed rape and sunflower.Developmental duration of larvae on soybean was also the longest(23.3 days).The highest pupation rate was recorded on sunflower.The highest pupal mass(0.19 g)was attained on oilseed rape,significantly higher than on the other host plants;the lowest mass was on soybean(0.15 g).On soybean,oilseed rape and sunflower,respectively,the average generation period was 42.21,39.10 and 40.44 d;the intrinsic rate of increase(r)was 0.0844,0.1041 and 0.1134;the finite rate of increase(λ)was 1.0881,1.1098 and 1.1202.While the most suitable host plant overall was sunflower,S.frugiperda completed development and increased its population on all three host plants.Thus,soybean,oilseed rape and sunflower were all suitable for FAW,and population monitoring and management of FAW in these crops should be increased.展开更多
Studying the population ecology of endangered plants provides important baseline information for its monitoring and conservation.Juniperus phoenicea L.is an endangered species in arid ecosystems in Africa and the Midd...Studying the population ecology of endangered plants provides important baseline information for its monitoring and conservation.Juniperus phoenicea L.is an endangered species in arid ecosystems in Africa and the Middle East.The static life tables,survival curve and age structure of J.phoenicea populations from two mountains in North Sinai,Egypt(Gabal(G.)El-Halal and G.El-Maghara)were investigated.In each mountain,fifteen plots were selected,and field measurements such as stand density,tree height,and crown diameter were conducted.Moreover,44 trees were cored and crossdated according to standard dendrochronological procedures.The results showed that the tree ages ranged from 50 to 262 years at G.El-Halal and 96 to431 years at G.El-Maghara.Mature J.phoenicea individuals dominated the study area,with only a few individuals being younger than 100 years.Moreover,seedling recruitment was extremely limited.Since the studied J.phoenicea populations showed high mortality rates among both old and young individuals,there is an imminent need for establishing a conservation program to prevent its extinction in the future.Therefore,management and conservation efforts should be made to minimize human disturbance and protect the relic habitats of this endangered species at its southern distribution limits in Africa.展开更多
Natural secondary forest has a strong capacity to regrow naturally and recover biodiversity rapidly on abandoned lands.However,at the neighborhood scale,which can truly reflect the facilitative or competitive interact...Natural secondary forest has a strong capacity to regrow naturally and recover biodiversity rapidly on abandoned lands.However,at the neighborhood scale,which can truly reflect the facilitative or competitive interactions among individual plants,the local diversity spatial structure in secondary forest and the feedback effects of neighborhood diversity on natural regeneration remain unclear,and this may be the key to properly understand the mechanisms of natural secondary forest species diversity recovery.To this end,this study established a dynamic plot in a rehabilitated secondary forest after disturbance and conducted a comprehensive survey of 68,336 individual plants with repeated measurements at 5-year interval to assess the characteristics of neighborhood diversity structure across life history stages and link the neighborhood species richness(NSR)effect translated by species interactions at species diversity structure with individual trees recruitment/mortality in secondary forest regeneration.The results showed that,compared with tropical and temperate natural forests,a higher proportion of diversity accumulators and a lower proportion of repellers in subtropical secondary forests resulted in neighborhood diversity structures characterized by heterospecific or high-diversity patches,which are beneficial to the maintenance or restoration of biodiversity.As an important supplement to the research on the relationship between diversity and productivity,our findings show a positive diversity-survival relationship in subtropical secondary forests.Importantly,we observed that the neighborhood diversity structure exhibited a trend of accumulator-dominated to neutral-dominant changes with life stage from sapling to adult,which,in turn,determined the direction and strength of NSR effects on recruitment/mortality.Specifically,diverse local neighborhoods at a later successional stage characterized with‘neutral’species-species interactions can act as a‘welfare net’by offering favorable microhabitats for the most vulnerable recruitments or saplings,i.e.,the NSR effects that promoted individual recruitment/survival in our study.These results not only enrich our understanding of the biodiversity-productivity-survival relationship but also highlight the importance of retaining latesuccessional species of native trees in intensive forest production or in situ conservation policies.展开更多
Genome size changes significantly among taxonomic levels,and this variation is often related to the patterns shaped by the phylogeny,life histories and ecological factors.However,there are mixed evidences on the main ...Genome size changes significantly among taxonomic levels,and this variation is often related to the patterns shaped by the phylogeny,life histories and ecological factors.However,there are mixed evidences on the main factors affecting molecular evolution in animals.In this study,we used phylogenetic comparative analysis to investigate the evolutionary rate of genome size and the relationships between genome size and life histories(i.e.,hatchling mass,clutch size,clutches per year,age at sexual maturity,lifespan and body mass)among 199 squamata species.Our results showed that the evolutionary rate of genome size in Lacertilia was significantly faster than Serpentes.Moreover,we also found that larger species showed larger hatchling mass,more clutches per year and clutch size and longer lifespan.However,genome size was negatively associated with clutch size and clutches per year,but not associated with body mass we looked at.The findings suggest that larger species do not possess the evolution of large genomes in squamata.展开更多
In the East China Sea(ECS),chub mackerel Scomber japonicus constitutes an important coastal-pelagic fishery resource that is mainly exploited by Chinese,Japanese,and Korean light-purse seine fisheries.Because the earl...In the East China Sea(ECS),chub mackerel Scomber japonicus constitutes an important coastal-pelagic fishery resource that is mainly exploited by Chinese,Japanese,and Korean light-purse seine fisheries.Because the early life history of chub mackerel plays a significant role in its recruitment,we developed an individual-based model to study the distribution,growth,and survival rate of chub mackerel larvae and juveniles in the ECS to improve our understanding of the chub mackerel population structure and recruitment.Our results show that as body length rapidly increases,the swimming capacity of chub mackerel larvae and juveniles improves quickly,and their spatial distribution depends more on their habitat conditions than the ocean currents.Correspondingly,the juveniles from the central and southern ECS spawning ground are scarcely recruited into the Japan/East Sea(JES)or the western Pacific Ocean,but a significant proportion of juveniles from the northern ECS spawning ground still enter the JES and there are exchanges between the stocks in the ECS and JES.Thus,it seems more reasonable to assess and manage the chub mackerels in the ECS and JES as a stock.The water temperature and ocean primary production in the ECS are two important factors influencing the chub mackerel habitat conditions and their spatial and temporal distribution are significantly different as the spawning time changes.Therefore,the spawning time and location play an important role in the growth and survival rate of the larvae and juveniles.Generally,when chub mackerel spawns at the southern ECS spawning ground in March,the larva and juvenile growth and survival rate is relatively high;as spawning time moves forward,higher growth and survival rates would be expected for the chub mackerel spawned coastward or northward.For specific spawning sites,early or delayed spawning will reduce the survival rate.展开更多
[Objectives]The paper was to observe the life history and living habits of Scopula subpunctaria in Shandong tea region.[Methods]The occurrence period and duration of each insect state,as well as duration of each insta...[Objectives]The paper was to observe the life history and living habits of Scopula subpunctaria in Shandong tea region.[Methods]The occurrence period and duration of each insect state,as well as duration of each instar larvae in various generations were investigated and statistically analyzed.[Results]There were 6 generations of S.subpunctaria per year in Shandong tea region.Different from southern tea region,S.subpunctaria survived the winter as pupae and larvae in tea trees in Shandong,and the duration of overwintering eggs was greatly affected by temperature.The generations of S.subpunctaria overlapped seriously.[Conclusions]The results provide a basis for the comprehensive treatment of S.subpunctaria in Shandong tea region.展开更多
In December 11,2018,the fall armyworm(FAW),Spodoptera frugiperda invaded China and has since impacted local maize,sorghum and other crops.Here,we draw on laboratory experiments to show how different host crops(i.e.,ma...In December 11,2018,the fall armyworm(FAW),Spodoptera frugiperda invaded China and has since impacted local maize,sorghum and other crops.Here,we draw on laboratory experiments to show how different host crops(i.e.,maize,sorghum,wheat and rice)and artificial diet affect larval growth and adult reproduction of one local FAW strain.Larval diet affected development duration,pupation rate,survival and emergence rate of pupae,and S.frugiperda adult fecundity.FAW attained the slowest larval development(19.4 days)on sorghum and the fastest(14.1 days)on artificial diet,with larvae attaining 99.6%survival on the latter food item.On rice,FAW larvae attained survival rate of 0.4%and were unable to pupate successfully.Pupation rate and pupal survival varied substantially between artificial diet and live plantlets at different phenological stages.Pupal weight was the highest(0.26 g)on artificial diet and the lowest(0.14 g)on sorghum,while FAW females reached the highest fecundity(699.7 eggs/female)on 2-leaf stage maize.Egg hatching rate equaled 93.6%on 4-or 5-leaf stage maize and 36.6%on artificial diet.FAW intrinsic rate of natural increase and the finite rate of increase varied between larval diets,reflecting how young maize leaves are the most suitable diet.Our findings can help to refine laboratory rearing protocols,devise population forecasting models or guide the deployment of‘area-wide’integrated pest management(IPM)modules in FAW-invaded areas of China and other Asian countries.展开更多
Age and body size a re critical for understanding life history evolution and ecology.In this study,the age and body size of the Shangcheng stout salamander,Pachyhynobius shangchengensis,from a population in Anhui Prov...Age and body size a re critical for understanding life history evolution and ecology.In this study,the age and body size of the Shangcheng stout salamander,Pachyhynobius shangchengensis,from a population in Anhui Province,China,were studied by skeletochronology.The mean age was 8.8±0.2(mean±SD)years in females and 9.6±0.2 in males and ranged 5-13 years for both sexes.The mean age was significantly different between sexes.The mean body size and mass were(100.21±0.91)mm and(31.76±0.73)g in females,and(105.31±1.23)mm and(37.14±1.12)g in males,respectively.Males were significantly larger and heavier than females,indicating sexual size dimorphism.There was a significant positive correlation among body size,body mass,and age,suggesting that the oldest individuals are larger and heavier.The growth rate in males was significantly higher than in females.The present study provides preliminary data on life-history traits which can be helpful for future studies of this species and other hynobiid salamanders.展开更多
基金provided by the National Natural Science Foundation of China (Grant 32071491, 31772465, 31672299, 31572271, and 32260128)the Natural Sciences Foundation of the Tibetan (XZ202101ZR0051G)。
文摘Two questions in the research of animal personality—whether there is a correlation between a personality trait and individual reproductive success,and what is the genetic basis underlying a personality trait—remain unresolved.We addressed these two questions in three shrub-nesting birds,the Azure-winged Magpie(Cyanopica cyanus,AM),White-collared Blackbird(Turdus albocinctus,WB),and Brown-cheeked Laughingthrush(Trochalopteron henrici,BL).The personality type of an individual was first identified according to its response to a territorial intruder.Then,we compared the fleeing distance,breeding parameters,and differential expressed genes(DEGs) in the brain transcriptome between bold and shy breeders.In the three species,bold breeders exhibited more aggressiveness towards an intruder of their territory than did shy breeders.The reproductive success of bold breeders was significantly higher than that of shy breeders in AM but not in WB and BL.The three species shared one DEG,crabp1,which was up-regulated in bold relative to in shy individuals.By regulating the expression of corticotropin-releasing hormone,higher crabp1 gene expression can decrease cellular response to retinoic acid.Therefore,bold individuals are insensitive to external stresses and able to exhibit more aggressiveness to intruders than their shier counterparts.Aggressiveness is beneficial to bold individuals in AM but not in WB and BL because the former could evoke neighbors to make the same response of defending against intruders but the latter could not.Although a personality trait may have the same genetic basis across species,its correlation with reproductive success depends largely on the life history style of a species.
基金Foundation item: The National Natural Science Foundation of China under contract No. 31570209.
文摘As the largest genus of Halymeniaceae,Grateloupia has been widely reported.Here,we observed the life history and early development of Grateloupia constricata Li et Ding and investigated the effects of temperature,irradiance,and photoperiod on the discoid crust and sporeling development of G.constricata under laboratory conditions.We observed that the type of carpospore development was“mediate discal type”.The life history included homotypic gametophyte(haploid),carposporophyte(diploid),and tetrasporophyte(diploid),with typical isomorphic alternation of generations.The results of double factorial analysis showed that both single factorial effects and interaction among temperature,photoperiod,and irradiance were obviously significant on the discoid crust and sporeling development.Furthermore,we found that the optimum combination of condition for the early growth and development of G.constricata was temperature 20°C,irradiance 80μmol photons/(m^2·s)and photoperiod 16L:8D.This study provides the theoretical basis and technical support for the conservation of the Grateloupia germplasm,artificial breeding,large-scale cultivation and sustainable development.
基金supported by the Fondazione Cariplo project CELLOW-FEEP:Circular economy:live larvae recycling organic waste as sustainable feed for rural poultry(ID 2019–1944)。
文摘Background:Black soldier fly(BSF)is one of the most promising species for the intensive breeding of insects given its adaptability and its efficiency in the conversion of waste.To maximize the production and use waste as substrates,it is essential to determine the larvae nutritional requirements.The study aims to evaluate the effects of5 practical,semi-purified and isoenergetic diets(PSPID)with increasing protein levels(10%,CP10;14%,CP14;16%,CP16;19%,CP19)on BSF life history traits.A total of 2000 six-day-old larvae were weighed and divided into groups of 100(4 replicates/treatment[PSPID and Gainesville diet(GA)used as environmental control]).In larva-prepupa stage,sampling was carried out on 30 individuals/replicate,while in prepupa-adult stage on 35.Results:In the whole larval stage,the CP16 treatment performed better when compared to the other groups.At18 days old,the CP14 treatment showed a higher weight than the CP19(P<0.01),while the CP10 and CP16weights were intermediate.On the contrary,the CP10 prepupae weight was higher than the CP19(P<0.01).The CP10 and CP14 pupae performed better in terms of weight when compared to the others(P<0.01).The dietary treatments did not affect the adult parameters.The sex significantly influenced both the exuvia weight,which was the greatest in females(P<0.001),and the fly lifespan,longest in males(P<0.05).Fly lifespan was also influenced by the interaction between treatment and sex,with the CP19 females showing a longer life than the others(P<0.05).Conclusions:In conclusion,the optimal protein level considering the whole larval stage is 16%on dry matter(DM).At 18 days old,looking at the size intended for the meal production,it can be considered 14%on DM.The result obtained on adult emergence in PSPID may not be attributable to the protein content.Further researches on macronutrients requirements determination have to be conducted to evaluate the substrates composition effects on BSF life history traits.
基金This work was financially supported by China Scholarship Council(202006330094).
文摘The complex life histories of demersal fishes are artificially separated into multiple stages along with changes in morphology and habitat.It is worth exploring whether the phenotypes expressed earlier and later during the life cycle are related or decoupled.The life stages of first year Pacific cod(Gadus macrocephalus)were tracked over different hatch years and regions to test whether the early life history had a long-lasting effect on subsequent growth.We further explored the contribution of growth in the early and subsequent life history stages to body size at the end of each stage.In addition to the accessory growth centre and the first annual ring,the other two checks on the otolith possibly related to settlement and entering deeper waters were identified in 75 Pacific cod individuals.The direct and indirect relationships among the life history stages was interpreted based on path analysis.The results showed that growth prior to the formation of the accessory growth centre had a significant effect on the absolute growth of the fish before and after settlement and migration to deep water.However,there was no or moderate evidence that early growth affected the body size at each stage,which was mainly regulated by growth during the stage.This study supports the lasting effect of early growth and clarifies that it affects size mainly by indirectly regulating staged growth.Quantifying the phenotype relationships and identifying the internal mechanisms form the basis for assessing population dynamics and understanding the processes behind the changes.
文摘Dogtooth tuna,Gymnosarda unicolor were sampled off the east coast of Australia(southwest Pacific Ocean)from 2007 to 2012.Ages were determined by examining thin transverse sections of their sagittal otoliths and were based on counts of alternating opaque and translucent zones(annual growth increments).Growth was rapid during the first year of life,after which growth in length was much reduced.Parameters of the constrained von Bertalanffy growth function(fork length-at-age)were L∞=1164.77(mm,FL)and K=0.44 year^(-1).Preliminary estimates of longevity indicate a maximum observed age of at least 20 years.There was a high degree of variation in the observed length and age of sexual maturity for G.unicolor.Despite this variation,the size at 50%maturity for female G.unicolor estimated in this study was 713 mm FL(<2 years of age).The diet of G.unicolor is very broad and covers a range of fish species.The life history characteristics of G.unicolor overall,indicate that this species may be somewhat resilient to fishing.However,reports of localised depletions,in association with heavy targeting by sports fishers,low effective population sizes and patchy recruitment indicate that this species is particularly vulnerable to overfishing.
基金The research was supported by Shenzhen Science and Technology Innovation Committee(JCYJ20170307143804397).
文摘There are no eternal individual lives so life continues by relaying with reproduction.Consequently,lifespan and fecundity are two essential genetic traits of life.The life history tradeoffs theory holds that there is an inverse relationship between lifespan and fecundity.This paper proposes two new concepts,i.e.,“lifespan of pathogens”and treatment of infections by“antibiogenesis”.The lifespan of pathogens is the time limitation of those tiny lives just as other large creatures.Notably,the lifespan of bacterium is the time interval from the cell division by which it is produced to next division by then its life ends and transforms to two new lives,or dies.Antibiogenesis means inhibiting generation of new lives.By the principle of life history tradeoffs,the lifespan of pathogens determines the speed of their proliferations and consequently the modality of infection.The treatment principle of antibiogenesis requires the duration of treatment to be determined by the lifespan of infected pathogens.The life history tradeoffs theory and the two concepts are helpful to understanding the pathobiology and shaping the clinical aspects of infectious diseases.
基金We are grateful to Mr Youfeng Zheng and Mr Daliang Fu of the Bangxi Natural Reserve of Hainan Province for their help in the course of field data collection.We sincerely thank anonymous reviewers for comments and suggestions that helped to improve the manuscript.The research was supported by the Key National Natural Science Foundation(Fund No.30430120)China Postdoctoral Fund No.20070410635 and the Introduction of Higher-Level-Talents Foundation of Central South University of Forestry and Technology(Fund No.101-0630).
文摘Understanding life history patterns,individual fitness and population fitness can assist with conservation of endangered species.Field data on life history traits(i.e.age specific fecundity,age specific mortality,age at first reproduction,litter size and adult life expectancy)were collected from 121 Hainan Eld’s deer(Cervus eldi hainanus Thomas,1918),an in situ herd of an endemic,rare and endangered cervid inhabiting Bangxi Natural Reserve of Hainan Island,from 1990 to 2002.First,we constructed a dynamic life table to analyze the life history pattern of the population,which showed that the difference between the average lifespan of males and females was not significant(P>0.05),and that the difference between the average lifespan of the whole Hainan Eld’s deer population and that of other Eld’s deer populations living in South Asia(P>0.05),North America(P>0.05)and Europe(P>0.05)was not significant.Second,we used individual reproductive success or number of offspring of a male over its lifetime to estimate male individual fitness.Statistic analysis showed that male individual fitness was not significantly correlated with total antler velvet mass.Third,we used the population intrinsic rate of increase to measure population fitness,and population fitness of Hainan Eld’s deer was compared with similar indexes of 5 other cervid species.Hainan Eld’s deer population fitness index was 0.012,the second lowest value relative to other cervids.Results indicated that this rare species is still endangered and is in need of additional protection.
基金supported by the National Natural Science Foundation of China (Grant Nos. 31672292, 31372201)the Natural Science Foundation of Hebei Province (C2017205059)
文摘Background: In temperate-breeding birds, individuals must adjust their physiological states from one life-history stage to another in response to changing conditions to maximize ecological fitness. Previous evidences have shown that body mass, size-corrected mass(SCM), and hematocrit(Hct) could be used as estimates of the energetic state of individuals to illustrate life-history trade-offs and individual quality in field physiology. Plasma alkaline phosphatase(ALP) plays critical roles in regulating the metabolism of energy but very limited information is known on its link with body mass or Hct.Methods: We determined the changes of plasma ALP levels in both early breeding and wintering stages of male Eurasian Tree Sparrows(Passer montanus), and examined the relationships between ALP and body mass, SCM, and Hct of the birds.Results: Our study showed that(1) in male Eurasian Tree Sparrows, body mass did not vary with life-history stage but plasma ALP activity significantly increased in the wintering stage compared to the breeding stage;(2) ALP activity was not correlated with individual body mass but was positively correlated with individual SCM and Hct. Such positive correlations, however, only occurred in the wintering but not in the breeding stages.Conclusions: Our results suggest that plasma ALP activities in free-living birds can be used as one of the indicators o body condition or nutritional status for analyzing individual variation in the wintering but not in the breeding stages. The life-history dependent relationships between plasma ALP activity and body condition may contribute to our better understanding of the trade-off between individual survival and reproduction in free-living animals.
基金We thank Professor Myron Zalucki,The University of Queensland,Australia for editing the final version of the manuscript prior to submission.This work was financially supported by the National Natural Science Foundation of China(Project no.31772173).
文摘Rickettsia consists of some of the most prevalent symbionts of insects and often plays a significant role in the biology of its hosts.Recently,a maternally inherited Torix group Rickettsia,provisionally named as RiTBt,was recorded in a species of notorious pest whitefly,tentatively named as Asia II 1,from the Bemisia tabaci complex.The role of this Rickettsia in the biology of its host is unknown.Here we investigated the impact of RiTBt on the performance and virus transmission capacity of Asia II 1.RiTBt did not significantly affect the life history parameters of the whitefly when the host insect was reared on tobacco,tomato,and cotton,three host plants with relatively low,medium and high suitability to the whitefly.Intriguingly,RiTBt slightly enhanced whitefly transmission of cotton leaf curl Multan virus(CLCuMuV),a virus that is transmitted by the whitefly in the field and has caused extensive damage to cotton production.Specifically,compared with whiteflies without RiTBt,following a 48 h virus acquisition whiteflies with RiTBt had higher titer of virus and showed higher efficiency of virus transmission.A rickettsial secretory protein BtR242 was identified as a putative virus-binding protein,and was observed to interact with the coat protein of CLCuMuV in vitro.Viral infection of the whitefly downregulated gene transcript levels of the BtR242 gene.These observations indicate that RiTBt has limited impact on the biology of the Asia II 1 whitefly,and whether this symbiont has functions in the biology of other host whiteflies warrants future investigation.
文摘In this paper we review and integrate key aspects of behavioral and life history traits, food supply and populationdynamics of the white-footed mouse (Peromyscus leucopus), a species that is abundant and widely distributedacross much of eastern North America. Results are based largely on a 33-year mark-and-recapture study in a forestfragment in northwest Ohio, USA. Behavioral plasticity in such reproductive traits as mating system and parentalcare allows this species to adjust quickly to changing environments. The species has a relatively “fast” life history,with rapid attainment of sexual maturity and high fecundity in the face of high mortality rates. Maximal reproductiveeffort early in life enables a rapid population response. Food supply, in the form of mast, determines thesize of the reproducing population in early spring, which, in turn, influences the size of the late summer peak population.The peak population size is also affected by short-term weather events possibly acting via the food supply.The effects of weather and food on population growth are in part mediated through competition, including defenseof space and suppression of reproduction. The inelasticity of female territories appears to set an upper limit topopulation density.
基金This study was supported financially by the Netherlands Organization for Scientific Research(NWO)that provided a Rubicon post-doctoral fellowship for CI(project no.825.07.004),the Australian Research Council(to MO and EW),the Hermon Slade Foundation(to EW)and the NWO-Vici(to JK).
文摘Recent research suggests that oxidative stress,via its links to metabolism and senescence,is a key mechanism linking life history traits such as fecundity and growth with survival;however,this has rarely been put under empirical scrutiny within free-living populations.Using a wild population of live-bearing skinks,we explored how plasma antioxidant activity(OXY),reactive oxidative metabolites(ROM),and the estimated oxidative stress index are associated with female and male life history.We found that male skinks have a significantly higher ROM and estimated oxidative stress index than female skinks,but this was not accompanied by a sex difference in mortality.Both sexes showed a non-linear association between OXY and age,indicating that the oldest and youngest individuals had the lowest OXY.Interestingly,female skinks with high OXY showed a decreased probability of survival to the following season.However,we found no significant associations between female reproductive investment(litter size or litter mass)or parturition date(i.e.metabolism)and oxidative status.Combined,our results offer mixed support for a role of oxidative stress in mediating life history traits and suggest that future studies need to explore oxidative stress during vitellogenesis in addition to using an intra-individual approach to understand the cost of reproduction and patterns of aging.
基金The authors wish to thank Bryant Hillas for revision of the final version of the manuscript.This work was sup-ported by grants from the Agencia Nacional de Promocion Cientifica y Tecnologica(Argentina)(PICT 2012-0640)the Universidad de Buenos Aires(Argentina)(UBA-CyT 20020100100482).NJL and JJF are members of Carrera del Investigador Cientifico of CONICET(Ar-gentina).MI,NE,and VEO are recipients of a scholarship from CONICET(Argentina).
文摘It has been demonstrated that phenotypic plasticity and genotype by envi-ronment interaction are important for coping with new and heterogeneous environments during invasions.Zaprionus indianus Gupta(Diptera:Drosophilidae)is an Afrotropical invasive fly species introduced to the South American continent in 1999.This species is generalist and polyphagous,since it develops and feeds in several different fruit species.These characteristics of Z.indianus suggest that phenotypic plasticity and genotype by environment interaction may be important in this species invasion process.In this sense,our aim was to investigate the role of genetic variation for phenotypic plasticity(geno-type by environment interaction)in Z.indianus invasion of the South American continent.Specifically,we quantified quantitative genetic variation and genotype by environment in-teractions of morphological and life history traits in different developmental environments,that is,host fruits.This was done in different populations in the invasive range of Z.indi-anus in Argentina.Results showed that Z.indianus populations have considerable amounts of quantitative genetic variation.Also,genotype by environment interactions was detected for the different traits analyzed in response to the different developmental environments.Interestingly,the amounts and patterns of these parameters differed between populations.We interpreled these results as the existence of diferences in evolutionary potential be-tween populations that have an important role in the short-and long-term success of the Z.indianus invasion process.
基金supported by the National Key R&D Program of China(2019YFD0300102)the earmarked fund for China Agriculture Research System(CARS-15-19)the Central Public-interest Scientific Institution Basal Research Fund,China(CAAS-ZDRW202007)。
文摘The fall armyworm(FAW),Spodoptera frugiperda,is a newly invasive,widespread agricultural pest in China.Understanding the suitability of the main field crops in Chinese agricultural system as host for this polyphagous herbivore is especially important for making control strategy.Here,after FAWs were fed three important oil-bearing crops(oilseed rape,soybean and sunflower)planted in China and resultant population parameters were compared using the age-stage,two-sex life table method,survival of larvae on soybean was significantly lower than that on oilseed rape and sunflower.Developmental duration of larvae on soybean was also the longest(23.3 days).The highest pupation rate was recorded on sunflower.The highest pupal mass(0.19 g)was attained on oilseed rape,significantly higher than on the other host plants;the lowest mass was on soybean(0.15 g).On soybean,oilseed rape and sunflower,respectively,the average generation period was 42.21,39.10 and 40.44 d;the intrinsic rate of increase(r)was 0.0844,0.1041 and 0.1134;the finite rate of increase(λ)was 1.0881,1.1098 and 1.1202.While the most suitable host plant overall was sunflower,S.frugiperda completed development and increased its population on all three host plants.Thus,soybean,oilseed rape and sunflower were all suitable for FAW,and population monitoring and management of FAW in these crops should be increased.
文摘Studying the population ecology of endangered plants provides important baseline information for its monitoring and conservation.Juniperus phoenicea L.is an endangered species in arid ecosystems in Africa and the Middle East.The static life tables,survival curve and age structure of J.phoenicea populations from two mountains in North Sinai,Egypt(Gabal(G.)El-Halal and G.El-Maghara)were investigated.In each mountain,fifteen plots were selected,and field measurements such as stand density,tree height,and crown diameter were conducted.Moreover,44 trees were cored and crossdated according to standard dendrochronological procedures.The results showed that the tree ages ranged from 50 to 262 years at G.El-Halal and 96 to431 years at G.El-Maghara.Mature J.phoenicea individuals dominated the study area,with only a few individuals being younger than 100 years.Moreover,seedling recruitment was extremely limited.Since the studied J.phoenicea populations showed high mortality rates among both old and young individuals,there is an imminent need for establishing a conservation program to prevent its extinction in the future.Therefore,management and conservation efforts should be made to minimize human disturbance and protect the relic habitats of this endangered species at its southern distribution limits in Africa.
基金supported by the Innovative Team Project of Nanjing Institute of Environmental Sciences,MEECentral Public Welfare Scientific Institution Basal Research Fund,Ministry of Finance and Ministry of Ecology and Environment of China(Nos.GYZX210302,GYZX200203):Biodiversity Survey,Observation and Assessment Program of Ministry of Ecology and Environment of China+2 种基金The National Environmental Protection Public Welfare Industry Targeted Research Fund:Research and demonstration of key technologies for dynamic supervision of nature reserves(No.201509042)The Special Foundation for National Science and Technology Basic Resources Investigation of China(No.2019FY202300)The Jiangsu Postdoctoral Research Funding Program(No.2021K038A)。
文摘Natural secondary forest has a strong capacity to regrow naturally and recover biodiversity rapidly on abandoned lands.However,at the neighborhood scale,which can truly reflect the facilitative or competitive interactions among individual plants,the local diversity spatial structure in secondary forest and the feedback effects of neighborhood diversity on natural regeneration remain unclear,and this may be the key to properly understand the mechanisms of natural secondary forest species diversity recovery.To this end,this study established a dynamic plot in a rehabilitated secondary forest after disturbance and conducted a comprehensive survey of 68,336 individual plants with repeated measurements at 5-year interval to assess the characteristics of neighborhood diversity structure across life history stages and link the neighborhood species richness(NSR)effect translated by species interactions at species diversity structure with individual trees recruitment/mortality in secondary forest regeneration.The results showed that,compared with tropical and temperate natural forests,a higher proportion of diversity accumulators and a lower proportion of repellers in subtropical secondary forests resulted in neighborhood diversity structures characterized by heterospecific or high-diversity patches,which are beneficial to the maintenance or restoration of biodiversity.As an important supplement to the research on the relationship between diversity and productivity,our findings show a positive diversity-survival relationship in subtropical secondary forests.Importantly,we observed that the neighborhood diversity structure exhibited a trend of accumulator-dominated to neutral-dominant changes with life stage from sapling to adult,which,in turn,determined the direction and strength of NSR effects on recruitment/mortality.Specifically,diverse local neighborhoods at a later successional stage characterized with‘neutral’species-species interactions can act as a‘welfare net’by offering favorable microhabitats for the most vulnerable recruitments or saplings,i.e.,the NSR effects that promoted individual recruitment/survival in our study.These results not only enrich our understanding of the biodiversity-productivity-survival relationship but also highlight the importance of retaining latesuccessional species of native trees in intensive forest production or in situ conservation policies.
基金Financial support was provided by the National Natural Sciences Foundation of China(31772451,31970393)the Science and Technology Youth Innovation Team of Sichuan Province(2019JDTD0012)。
文摘Genome size changes significantly among taxonomic levels,and this variation is often related to the patterns shaped by the phylogeny,life histories and ecological factors.However,there are mixed evidences on the main factors affecting molecular evolution in animals.In this study,we used phylogenetic comparative analysis to investigate the evolutionary rate of genome size and the relationships between genome size and life histories(i.e.,hatchling mass,clutch size,clutches per year,age at sexual maturity,lifespan and body mass)among 199 squamata species.Our results showed that the evolutionary rate of genome size in Lacertilia was significantly faster than Serpentes.Moreover,we also found that larger species showed larger hatchling mass,more clutches per year and clutch size and longer lifespan.However,genome size was negatively associated with clutch size and clutches per year,but not associated with body mass we looked at.The findings suggest that larger species do not possess the evolution of large genomes in squamata.
基金Supported by the National Natural Science Foundation of China(No.32072981)。
文摘In the East China Sea(ECS),chub mackerel Scomber japonicus constitutes an important coastal-pelagic fishery resource that is mainly exploited by Chinese,Japanese,and Korean light-purse seine fisheries.Because the early life history of chub mackerel plays a significant role in its recruitment,we developed an individual-based model to study the distribution,growth,and survival rate of chub mackerel larvae and juveniles in the ECS to improve our understanding of the chub mackerel population structure and recruitment.Our results show that as body length rapidly increases,the swimming capacity of chub mackerel larvae and juveniles improves quickly,and their spatial distribution depends more on their habitat conditions than the ocean currents.Correspondingly,the juveniles from the central and southern ECS spawning ground are scarcely recruited into the Japan/East Sea(JES)or the western Pacific Ocean,but a significant proportion of juveniles from the northern ECS spawning ground still enter the JES and there are exchanges between the stocks in the ECS and JES.Thus,it seems more reasonable to assess and manage the chub mackerels in the ECS and JES as a stock.The water temperature and ocean primary production in the ECS are two important factors influencing the chub mackerel habitat conditions and their spatial and temporal distribution are significantly different as the spawning time changes.Therefore,the spawning time and location play an important role in the growth and survival rate of the larvae and juveniles.Generally,when chub mackerel spawns at the southern ECS spawning ground in March,the larva and juvenile growth and survival rate is relatively high;as spawning time moves forward,higher growth and survival rates would be expected for the chub mackerel spawned coastward or northward.For specific spawning sites,early or delayed spawning will reduce the survival rate.
文摘[Objectives]The paper was to observe the life history and living habits of Scopula subpunctaria in Shandong tea region.[Methods]The occurrence period and duration of each insect state,as well as duration of each instar larvae in various generations were investigated and statistically analyzed.[Results]There were 6 generations of S.subpunctaria per year in Shandong tea region.Different from southern tea region,S.subpunctaria survived the winter as pupae and larvae in tea trees in Shandong,and the duration of overwintering eggs was greatly affected by temperature.The generations of S.subpunctaria overlapped seriously.[Conclusions]The results provide a basis for the comprehensive treatment of S.subpunctaria in Shandong tea region.
基金supported by the earmarked fund for China Agriculture Research System(CARS-15-19)the Central Public-interest Scientific Institution Basal Research Fund,China(Y2019YJ06)。
文摘In December 11,2018,the fall armyworm(FAW),Spodoptera frugiperda invaded China and has since impacted local maize,sorghum and other crops.Here,we draw on laboratory experiments to show how different host crops(i.e.,maize,sorghum,wheat and rice)and artificial diet affect larval growth and adult reproduction of one local FAW strain.Larval diet affected development duration,pupation rate,survival and emergence rate of pupae,and S.frugiperda adult fecundity.FAW attained the slowest larval development(19.4 days)on sorghum and the fastest(14.1 days)on artificial diet,with larvae attaining 99.6%survival on the latter food item.On rice,FAW larvae attained survival rate of 0.4%and were unable to pupate successfully.Pupation rate and pupal survival varied substantially between artificial diet and live plantlets at different phenological stages.Pupal weight was the highest(0.26 g)on artificial diet and the lowest(0.14 g)on sorghum,while FAW females reached the highest fecundity(699.7 eggs/female)on 2-leaf stage maize.Egg hatching rate equaled 93.6%on 4-or 5-leaf stage maize and 36.6%on artificial diet.FAW intrinsic rate of natural increase and the finite rate of increase varied between larval diets,reflecting how young maize leaves are the most suitable diet.Our findings can help to refine laboratory rearing protocols,devise population forecasting models or guide the deployment of‘area-wide’integrated pest management(IPM)modules in FAW-invaded areas of China and other Asian countries.
基金supported by the National Natural Science Foundation of China(NSFC 31471971)to Jianli XIONGgrants from the National Natural Science Foundation of China(NSFC 31272332)to Baowei ZHANG。
文摘Age and body size a re critical for understanding life history evolution and ecology.In this study,the age and body size of the Shangcheng stout salamander,Pachyhynobius shangchengensis,from a population in Anhui Province,China,were studied by skeletochronology.The mean age was 8.8±0.2(mean±SD)years in females and 9.6±0.2 in males and ranged 5-13 years for both sexes.The mean age was significantly different between sexes.The mean body size and mass were(100.21±0.91)mm and(31.76±0.73)g in females,and(105.31±1.23)mm and(37.14±1.12)g in males,respectively.Males were significantly larger and heavier than females,indicating sexual size dimorphism.There was a significant positive correlation among body size,body mass,and age,suggesting that the oldest individuals are larger and heavier.The growth rate in males was significantly higher than in females.The present study provides preliminary data on life-history traits which can be helpful for future studies of this species and other hynobiid salamanders.
