Correlation of personality with individual reproductive success in shrub-nesting birds depends on their life history style

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.

A preliminary study on life history of marine red alga Stylonema alsidii(Zandardini)Drew f.ramosum Zheng et Li

Stylonema alsidii(Zandardini)Drew f.ramosum Zheng et Li is a common species in the genus Stylonema,but there are limited reports on morphological taxonomy and a lack of studies on life history and the regulation of early development.The early development,discoid formation,and erect thallus growth of Stylonema alsidii f.ramosum were observed under laboratory conditions.In addition,the influence of main environmental factors such as temperature and light intensity on its development was briefly studied,and various stages of its life history were observed.The result shows:(1)there are two reproductive modes:asexual reproduction and sexual reproduction;(2)the morphology of this species varies in different degrees under laboratory culture conditions;(3)sexual reproduction and asexual reproduction can coexist under suitable conditions.Five pathways of life history were inferred from experimental phenomena.Mature sporophytes form mature gametophytes by producing initially isolated or initially attached monospore,and mature gametophytes form mature sporophytes by fertilization of eggs and sperms.The sexual and asexual reproduction processes of Stylonema alsidii f.ramosum were reported for the first time,and this is also the first report on sexual reproduction in the genus Stylonema.

Re-identifying Grateloupia yangjiangensis(Rhodophyta, Halymeniaceae) based on morphological observations, life history and rbcL sequence analyses

On the basis of morphological observations, life history and molecular phylogeny, Grateloupia yangjiangensis, which is similar to G. filicina, G. orientalis, G. catenata, and G. ramosissima in appearance, was re-examined. The results are as follows：（1） the auxiliary-cell ampullae of G. yangjiangensis were of Grateloupia type, thalli was fleshy and gelatinous in texture, and the erect axes were compressed; the cortex was 0.25–0.30 mm thick, consisting of five to seven outer layers, and there were five inner layers of triangular or stellate cells;（2） there was no filamentous stage in the development of the carpospores;（3） the ribulose-1,5-bisphosphate carboxylase/oxygenase gene（rbcL） sequence of four G. yangjiangensis examined showed that there was no intergeneric divergence among them, and for the phylogenetic tree, four sequences of G. yangjiangensis formed a single monophyletic subclade within the large Grateloupia clade of Halymeniaceae. In conclusion, G. yangjiangensis was a single species within the genus Grateloupia. This research provided criterion for identification and cultivation of G. yangjiangensis.

Study on fish life history traits and variation in the Taiwan Strait and its adjacent waters

Large portions of the world＇s fishery resources are overexploited. Life history traits of fish species are important indicators to reveal different life history strategies and to indicate population responses to fishing pressures. For this study, empirical data on fishing grounds located in the coastal area between Fujian Coast and Taiwan Island were collected. These areas have experienced severe overfishing in the past 30 years, leading to changes in the structure and function of the fish communities. Fifty-one commercial fish species in this fishing ground were selected to study the life history traits. Using the life history traits, all the species were grouped into five different life history strategies by principle component analysis. More than 60% of the species were categorized in Group 5 that was similar to r-strategists. Twenty-five commercial species were selected for further analysis of changes in life history variables, and to discuss the population responses to exploitation. Results showed that most of the species appeared to become smaller size, shorter life, earlier maturation and faster growing under long-term exploitation. The exploitation rate of each species was also calculated to further discuss the impacts of fishing pressures to fish populations. Four species were found with the severest changes on life history traits indicating some of the species might be more susceptible to exploitation. This study on fish life history traits and their long-term variations under fishing pressures could provide important scientific implications for fishery management and conservation.

Early development,life history and ecological habits of Grateloupia constricata Li et Ding

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.

Life History Traits and Mechanisms of Endangerment in Ranalisma rostratum

Ranalisma rostratum (Alismataceae) is an endangered aquatic plant, and now there is only one population existing in China. In its natural habitat, Huli marsh in Chaling, Hunan province, the best growing plants have been observed at microsites where the water depth is 5～10cm, and the plants grow in emergent form.R. rostratum reproduces asexually or sexually. The recruitment of asexual propagules into population is a very important way to maintain the natural population size. Although seed production does not appear to limitR. rostratum, restricted dispersal of propagules and seeds, low seed viability, low germinability, slow growth of seedlings under all conditions, and habitat loss due to agriculture appear to be more important reasons for the endangerment of this plant.

Isoenergetic-practical and semi-purified diets for protein requirement determination in Hermetia illucens larvae:consequences on life history traits

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.

Life History Research in Education

Life history research,as one of the most powerful research methods in sociology,brings some re-freshened air into interpretive research.In this paper,the development of life history research,from modernism to postmodernism,from life story to life history,is firstly illustrated.Then the process of conducting life history research is analyzed specifically,which is followed by its unique strengths.Finally,its issues,its general issues and its special issues in Chinese context,are critically examined.

Effects of Microcystis aeruginosa on life history of water flea Daphnia magna

Cyanobacterial blooms in eutrophic freshwater systems are a worldwide problem, creating adverse effects for many aquatic organisms by producing toxic microcystins and deteriorating water quality. In this study, microcystins (MCs) in Microcystis aeruginosa, and Daphnia magna exposed to M. aeruginosa, were analyzed by HPLC-MS, and the effects of M. aeruginosa on D. magna were investigated. When D. magna was exposed to M. aeruginosa for more than 2 h, Microcystin-LR (MC-LR) was detected. When exposed to 1.5 × 106, 3 × 106, 0.75 × 107, and 1.5 × 107 cell/mL of M. aeruginosa for 96 h, average survival of D. magna for treatments were 23.33%, 33.33%, 13.33%, 16.67%, respectively, which were significantly lower than the average 100% survival in the control group (P < 0.05). The adverse effects of M. aeruginosa on body length, time for the first brood, brood numbers, gross fecundity, lifespan, and population growth of D. magna were density-dependent. These results suggest that the occurrence of M. aeruginosa blooms could strongly inhibit the population growth of D. magna through depression of survival, individual growth and gross fecundity. In the most serious situations, M. aeruginosa blooms could undermine the food web by eliminating filter-feeding zooplankton, which would destroy the ecological balance of aquaculture water bodies.

Significant Effects of Fishing Gear Selectivity on Fish Life History

Over the past few decades, extreme changes have occurred in the characters of exploited fish populations. The majority of these changes have affected the growth traits of fish life history, which include a smaller size-at-age, an earlier age-at-maturation and among others. Currently, the causes of these life history traits changes still require systematic analyses and empirical studies. The explanations that have been cited are merely expressed in terms of fish phenotypic adaptation. It has been claimed that the original traits of fish can be recovered once the intensity of exploitation of the fish is controlled. Sustained environmental and fishing pressure will change the life history traits of most fish species, so the fish individual's traits are still in small size-at-age and at earlier age-at-maturation in exploited fish populations. In this paper, we expressed our view of points that fishing gear has imposed selectivity on fish populations and individuals as various other environmental factors have done and such changes are unrecoverable. According to the existing tend of exploited fish individual's life history traits, we suggested further researches in this field and provided better methods of fishery management and thereby fishery resources protection than those available early.

Temperature Effect on the Life History of Three Types of Brachionus calyciflorus Females

The effect of temperature on the life history characteristics of amictic females (AF), unfertilized mictic females (UMF) and fertilized mictic females (FMF) in Brachionus calyciflorus was studied with replicated individual cultures at 20℃,25℃ and 30℃, and with algae Scenedesmus obliquus for their food. There were highly significant effects of both temperature and female type, independently and interactively, on the duration of juvenile and post-reproduction periods, and the number of eggs produced by the rotifer per life cycle. Among all the temperature-female type combinations, all the juvenile periods of FMF, and the post-reproduction periods of UMF and FMF at 20℃, were the longest, and the number of eggs produced by an UMF at 30℃ was the highest. There were highly significant effects of both temperature and female type on the duration of the reproduction period, but no clear correlation was observed between temperature and female type. The reproduction period of AF was longer than that of UMF and FMF. Only temperature influenced significantly the mean life-span of the three types of females. The duration of juvenile, reproduction and post-reproduction periods as well as the life-span of the three types of females were all reduced very significantly with rise of temperature, but the rates of reduction varied with female type. Among the three types of females, the number of eggs produced per life cycle by an UMF was the highest, and that of a FMF was the lowest. A significant relationship between the number of eggs produced per life cycle and temperature was observed only in the UMF.

Sexual Fusion and Life History of Scytosiphon lomentaria (Scytosiphonaceae, Phaeophyceae) in Dalian, China

Morphology and life history of a brown alga Scytosiphon lomentaria (Lyngbye) Link (Scytosiphonaceae, Phaeophyceae) were investigated from 2005 to 2009 in the coastal waters of Dalian, China. The erect thalli collected in the field were tubular, hollow, and commonly constricted at intervals. Ascocysts were presented. Plurilocular gametangia, which were positioned in continuous sori on the erect thallus surface, produced biflagellar gametes. Gametophytes were dioecious and gametes were nearly isogamous. Gametes fusion occurred in three types. Type one, female and male gametes fused directly while swimming; type two, female gamete settled first, with which a male one contacted and fused rapidly; type three, while settling adjacently, a male gamete's entire protoplast moved slowly into the previously settled female one, with only an empty cell membrane left. In culture zygotes developed into crustose sporophytes that formed unilocular sporangia. Biflagellar zoospores developed into erect thalli that formed plurilocular gametangia. The results indicated that a periodical heteromorphic alternation history with haploid gametophyte generation and diploid sporophyte generation exists in S. lomentaria of the Dalian populations.

Opportunistic-tended life history traits of Siniperca kneri in the Three Gorges Reservoir,China: potential responses to impoundment

Reservoir impoundment changes original fluvial habitats into lentic environments. Fish species adapted to lentic habitats may take the advantage of such habitat changes and show typical life history traits might facilitate the population increase. Siniperca kneri rarely occurred in fishery landing in the Three Gorges Reservoir (TGR) area before its impoundment in 2003, but it is now a dominant species. In this study, a total of 438 females of S . kneri were collected monthly during September 2012 through January 2014 using gill nets in the TGR. The age, growth, and reproductive biology were then investigated, and compared with other S . kneri populations. The standard length at age 1 was 149.9 mm in the TGR, which is larger than the three compared populations (i.e., Sandaohe Reservoir, Xinfengjiang Reservoir, and North River), but smaller than one (the Guishi Reservoir). The youngest mature female in the TGR was age 1, which is younger than that of the two compared populations (i.e., Xinfengjiang Reservoir and the North River). The relative fecundity in the TGR was 140 eggs/g, which is higher than that of the only available compared population (Xinfengjiang Reservoir, 96 eggs/g). Our results demonstrated that S . kneri in the TGR tended to have faster growth in the first year, a younger age at first maturation, and higher reproductive eff ort. We suggest that such opportunistic-tended life history traits might facilitate rapid increase of the population.

Study on Life History and Daily Rhythm of Gilpinia yongrenica

The life history and adult daily rhythm of Gilpinia yongrenica Xiao et Huang in Guizhou Province were observed and recorded.The results showed that there were three generations of G.yongrenica in Guizhou area;the first generation occurred from late March to middle July;the second generation occurred from early June to middle October;and the third generation occurred from middle September to late April.The ratio of male to female was 5.75∶1,and the emergence rate was 88.25%.The emergence of adults changed significantly with time,and the peak emergence period was at 12:00-13:00.The resting behavior accounted for the largest proportion in daily time distribution of adult behavior;followed by moving behavior and spawning behavior;and the mating behavior accounted for the smallest proportion.The moving behavior mainly occurred during the daytime,which reached the peak at 8:00-11:00.The resting behavior mainly occurred at 19:00-7:00,with the maximum reaching 100%.The mating behavior was concentrated at 12:00-13:00,which reached the peak at 13:00(19.5%).The spawning behavior mainly occurred at 14:00-15:00,and reached the peak at 14:00(42.1%).

Preliminary age-based life history characteristics of the dogtooth tuna,Gymnosarda unicolor(Ruppell,1838),in the southwest Pacific Ocean

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.

Early life history affects fish size mainly by indirectly regulating the growth during each stage:a case study in a demersal fish

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.

Textual research on Xu Chunfu's life

Xu Chunfu was a famous medical expert in the Ming Dynasty, who authored the Gu Jin Yi Tong Da Quan and the Yi Xue Zhi Nan Jie Jing Liu Shu. This paper uses the Xu family genealogy, literature catalog, historical records to study the Xu family’s life and deeds. Xu Chunfu was born in the second year of the Jiajing reign of the Ming Dynasty (1523) and passed away in the 24th year of the Wanli reign of the Ming Dynasty (1596). He served as an official in the Tai Hospital for about 20 years. His work Gu Jin Yi Tong Da Quan was written around the 43rd year of the Jiajing reign of the Ming Dynasty (1556), with a lower limit of the fifth year of the Longqing reign of the Ming Dynasty (1571), and the initial engraving time was not earlier than the eighth year of the Wanli reign of the Ming Dynasty (1580). This paper corrects the shortcomings and errors in previous research, and provides a comprehensive and systematic examination of Xu Chunfu’s life and works.

Phenotypic Plasticity of Life History Characteristics: Quantitative Analysis of Delayed Reproduction of Green Foxtail (Setaria viridis) in the Songnen Plain of China

Green foxtail （Setaria viridis L.） is a common weed species in temperate regions. Research on the effect of delayed reproduction on the phenotypic plasticity and regularity of the vegetative and reproductive growth is of vital significance for understanding population regulation and control of the weed in the growing season. Green foxtail seeds were sown every 10 days from 25 June to 24 August of 2004. The growth and production metrics were measured via harvesting tufts and statistical analysis was carried out. The results showed that the reproductive tillers, seed number, seed biomass and one thousand-seed weight of plants at the first sowing （25 June） approximately increased 28.8, 7 827.0, 1 104,0 and 12.3 times compared with that at the last sowing （24 August）, respectively. Total tillers, reproductive tillers and height increased linearly as the reproductive period delayed, however, biomass increased exponentially. Quadratic equations best explained the relationships between the delayed reproductive period and seed number, inflorescence length, one thousand-seed weight, seed biomass. Based on the quantity and quality of seed production, weeding young seedlings emerging before July can be the most effective weed-control strategy in the Songnen Plain.

Life history tradeoffs of pathogens and the treatment principle of antibiogenesis

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.