Reproductive Ecology Research Articles

Reproductive ecology and natural history of Kinosternon herrerai (Testudines: Kinosternidae) at the center of its distribution


 
 
 
 Mexico harbors 10 endemic species of mud turtles of genus Kinosternon, but natural history information is lacking for most of them. Herein we describe some generalities of the reproductive ecology and natural history of one population of the Mexican endemic, Herrera’s mud turtle, K. herrerai from Hidalgo, Mexico. Females and males were similar in body mass and carapace length. Additionally, larger and heavier turtles moved more than smaller and lighter ones. Clutch size varied from one to six eggs, with an average of 3.4 ± 1.7, and egg laying occurred at environmental temperatures between 15 and 21°C (x̅ = 18.6°C). Total nesting time (from selection of nesting site to oviposition) lasted ca. 37 min, and the incubation period was 75 days in situ. These results enhance our understanding of natural history aspects of Kinosternon mud turtles, which are necessary to carry out conservation actions to preserve all of its populations.
 
 
 

Reproductive ecology of Dianthus inoxianus: A rare wild carnation with a specialized pollination system

Plants with specialized pollination systems may be susceptible to reproductive failure when pollinator service is unpredictable. This can influence the selection of floral traits that promote outcrossing in the presence of pollinators and selfing in their absence. Limited evidence exists regarding the association between specialized pollination and reproductive assurance, necessitating further investigation. We studied the reproductive biology of Dianthus inoxianus, a rare Mediterranean carnation endemic to a semi-arid region in SW Spain. D. inoxianus exhibited protandrus flowers and additional phenotypic signs of specialization for nocturnal pollination. Nectar sugar concentration remains relatively constant throughout the day (average 33.4%), while the standing crop varies considerably (average 1.5 μL/flower), peaking in the late afternoon and early evening. Controlled hand pollinations revealed that D. inoxianus is fully self-compatible, with similar reproductive success in autogamous, geitonogamous, and allogamous crosses. However, a small proportion of bagged flowers exhibited autonomous selfing. To assess the impact of presumed nocturnal pollination, we studied reproductive fitness and flower visitors over five years in three populations. Over 210 h of pollinator censuses, the hawkmoth species Hyles livornica and Macroglossum stellatarum, which were mainly dusk-active, accounted for > 95% of flower visits. Fruit and seed set positively correlated with hawkmoth visitation rate across years and populations. Additionally, pollinator exclusion experiments demonstrated that reproduction relies predominantly on nocturnal pollinators. However, under natural conditions, D. inoxianus also showed a non-negligible degree of autonomous self-pollination, with fruit- and seed-set being equivalent in absence of pollinators or under diurnal pollinators. We found evidence of an ecologically specialized pollination system and capacity for autonomous selfing, a combination that may enable the persistence of this taxon in a markedly unpredictable pollination environment.

Activity budget and gut microbiota stability and flexibility across reproductive states in wild capuchin monkeys in a seasonal tropical dry forest

BackgroundEnergy demands associated with pregnancy and lactation are significant forces in mammalian evolution. To mitigate increased energy costs associated with reproduction, female mammals have evolved behavioural and physiological responses. Some species alter activity to conserve energy during pregnancy and lactation, while others experience changes in metabolism and fat deposition. Restructuring of gut microbiota with shifting reproductive states may also help females increase the energy gained from foods, especially during pregnancy. The goal of this study was to examine the relationships among behaviour, gut microbiota composition, and reproductive state in a wild, non-human primate to better understand reproductive ecology. We combined life history data with > 13,000 behavioural scans and 298 fecal samples collected longitudinally across multiple years from 33 white-faced capuchin monkey (Cebus imitator) females. We sequenced the V4 region of the 16S rRNA gene and used the DADA2 pipeline to analyze microbial diversity. We used PICRUSt2 to assess putative functions.ResultsReproductive state explained some variation in activity, but overall resting behaviours were relatively stable across pregnancy and lactation. Foraging was less frequent among females in the early stage of nursing compared to the cycling stage, though otherwise remained at comparable levels. Maximum temperature was a strong, significantly positive predictor of resting, while social dominance had a small but significantly negative effect on resting. Ecological variables such as available fruit biomass and rainfall had a small but significantly positive effects on measures of foraging time. Gut microbial community structure, including richness, alpha diversity, and beta diversity remained stable across the reproductive cycle. In pairwise comparisons, pregnant females exhibited increased relative abundances of multiple microbial ASVs, suggesting small changes in relation to reproductive state. Reproductive state was not linked to differential abundance of putative metabolic pathways.ConclusionsPrevious data suggest that activity budget and the gut microbiome shifts considerably during reproduction. The present study finds that both activity and gut microbial communities are less associated with reproduction compared to other predictors, including ecological contexts. This suggests that behavioural flexibility and gut microbial community plasticity is contrained by ecological factors in this population. These data contribute to a broader understanding of plasticity and stability in response to physiological shifts associated with mammalian reproduction.

Does ash dieback affect the reproductive ecology of Fraxinus excelsior L.?

Forest tree species reproduction is a key factor in maintaining the genetic diversity of future generations and the stability of forest ecosystems. The ongoing ash dieback disease could affect the reproductive ecology of Fraxinus excelsior L. and have a major impact on the quantity and quality of pollen and seeds. In this study, we investigated pollen production and viability of pollen and seeds of ash trees with different health status from 2018 to 2022. Inflorescences were collected from 105 trees (pollen production), pollen from 125 trees (pollen viability), and seeds from 53 trees (seed quality) in two seed orchards and in one floodplain forest in southern Germany. Not all parameters were examined at every site every year. The average pollen production per tree was estimated at 471.2 ± 647.9 billion pollen grains. In addition, we found that a high number of inflorescences did not equate to high pollen production per inflorescence. Pollen production of healthy and diseased trees did not differ significantly, although only 47% of severely diseased male trees (vs. 72% for healthy trees) produced flowers. With regards to pollen viability, the TTC test showed an average viability of 73% ± 17%. Overall, there was a slight tendency for diseased trees to have less viable pollen. However, a significant difference could only be calculated for trees in the floodplain forest. The percentage of germinable seeds in 2018 was 38% in the floodplain forest and 57% in one of the seed orchards. The percentage of viable seeds (TTC test) ranged from 17 to 22% in the orchards in 2020. Non-viable seeds were usually heavily infested by insects. In general, seed quality was not significantly different between healthy and diseased trees. Our results indicate that ash dieback affects flower formation and pollen viability but not pollen production or seed quality. Nevertheless, the fact that hardly any flowering was observed, especially for trees that were seriously affected, suggests a negative effect of ash dieback on reproductive performance. Thus, severely diseased trees will transfer their genes to a smaller extent to the next generation.

Biological Aspects of Preferred Fish Species in White Volta at Pwalugu, Ghana: A pre-impoundment Study

The socio-economic benefits derived from impounding rivers are extremely important but the ecological imbalances that are usually created in the process can be devastating. It is therefore imperative to understand some aspects of the biology of fishes before the impoundment of a river. This study was conducted to assess the length-weight relationship, condition factor, feeding, and reproductive ecology of fish species with high local market value. Biometric measurements were obtained from monthly samples of fish at two sites. Specimens were transported to the laboratory for gut and gonad analyses. Auchenoglanis occidentalis, Marcussenius senegalensis and Heterobranchus bidorsalis were the most preferred fish species. All three fish species recorded ‘b’ values less than 3 which implies they exhibited a negative allometric growth. Their condition factors (K) indicated they were in good health since K values were greater than 1. A. occidentalis and H. bidorsalis demonstrated a feeding habit comparable to that of an omnivore, whilst M. senegalensis presented a feeding habit that implied it was an invertivore. M. senegalensis registered the uppermost mean gonado-somatic index (GSI) (2.14 ± 0.83) whereas the highest mean fecundity (495 ± 450.96) was noted in A. occidentalis. This study contributed bio-ecological baseline information about the ichthyofauna prior to the damming of the reservoir in the Pwalugu area of the White Volta.

A chimpanzee’s time to feast: seasonality of Macrotermes flight hole activity and alate dispersal flights detected by termite-fishing experiments and camera traps in the Issa Valley, Tanzania

IntroductionInvestigation into chimpanzee termite-fishing behavior has provided invaluable insights into the evolution of animal tool use and culture. However, research to date often overlooks how the ecology of termites may shape the nature of this predator–prey interaction. Though anecdotal links between meteorological factors, termite dispersal flights and the ability of chimpanzees to termite-fish have been made, these relationships were never empirically tested. In this study, we examined if and how the reproductive ecology of mound building termites (Macrotermes subhyalinus) affects the availability of this resource to termite-fishing chimpanzees in the Issa Valley, Tanzania.MethodsWe utilized in-person termite-fishing experiments, remote camera trap footage, as well as meteorological data to model both the availability of termite prey across seasons for chimpanzees as well as the timing of dispersal flights of the termite reproductive caste (alates). Additionally, we describe the predator diversity that characterizes alate swarming events during their seasonal dispersal flights.ResultsWe identify strong relationships between meteorological factors, Macrotermes alate dispersal flights and vulnerability of the colony to predation. As rainfall accumulates, Macrotermes become more abundant in their flight holes and are thus more vulnerable to researcher termite-fishing experiments. This increased accessibility to Macrotermes continues until alate dispersal flights which we also find are linked to cumulative rainfall as well as negatively correlated to wind speed.DiscussionThis type of baseline data on Macrotermes ecology is fundamental when forming hypotheses and designing studies into topics such as chimpanzee culture, tool-use, and foraging cognition.

Egg-Focused Aspects of the Reproductive Ecology of Black-Winged Stilts Himantopus himantopus and Pied Avocets Recurvirostra avosetta Coexisting in an Unstable Wetland in the Sahara (Algeria)

Egg-Focused Aspects of the Reproductive Ecology of Black-Winged Stilts Himantopus himantopus and Pied Avocets Recurvirostra avosetta Coexisting in an Unstable Wetland in the Sahara (Algeria)

Integrated metabolome and transcriptome reveals the mechanism of the flower coloration in cashew Anacardium occidentale

Cashew is a widely attractive food in the world with high nutritional value for human health. Flower color is an important trait that plays a key role in reproductive ecology and species evolution in cashew plants. In this study, we chose two cashew cultivars for research objects characterized as different flower coloration. B2_5 exhibited steady white color during flowering, while B7 exhibited a color transition from white to red in its blooming period. However, the molecular mechanisms underlying flower coloration in both cashew cultivars remains unclear. By comparative metabolome analysis, we identified 8 flavonoid compounds were markedly accumulated in B7 during flowering, especially delphinidin-3-O-glucoside and peonidin-3-glucoside. These hub metabolites explained the variety difference in flower coloration between B7 and B2_5 cashew cultivars. Further transcriptome analysis identified 9 key structural genes in flavonoid biosynthesis that were significantly up-regulated, especially CHI, FLS and LAR, which explained the variety difference in flower coloration between both cashew cultivars. The construction of co-expression network showed RAP2-2, NAC22, MYB78, MYB62 and MYB1 probably modulated the expression of three candidate structural genes. This study sheds light on the molecular mechanism of flower coloration in B7 cultivar and reveals the variety difference in flower coloration between two cultivars, these results expect to provide a worthy guidance for flower coloration in cashew.

A trait dataset for freshwater mussels of the United States of America

The United States of America has a diverse collection of freshwater mussels comprising 301 species distributed among 59 genera and two families (Margaritiferidae and Unionidae), each having a unique suite of traits. Mussels are among the most imperilled animals and are critical components of their ecosystems, and successful management, conservation and research requires a cohesive and widely accessible data source. Although trait-based analysis for mussels has increased, only a small proportion of traits reflecting mussel diversity in this region has been collated. Decentralized and non-standardized trait information impedes large-scale analysis. Assembling trait data in a synthetic dataset enables comparison across species and lineages and identification of data gaps. We collated data from the primary literature, books, state and federal reports, theses and dissertations, and museum collections into a centralized dataset covering information on taxonomy, morphology, reproductive ecology and life history, fish hosts, habitats, thermal tolerance, geographic distribution, available genetic information, and conservation status. By collating these traits, we aid researchers in assessing variation in mussel traits and modelling ecosystem change.

The breeding systems and floral visitors of two widespread African dry forest species of ethnobotanical significance.

Forest products derived from woody trees, such as fruits, seeds, honey, wood and others, are important resources for supporting rural livelihoods. However, little is known about the breeding systems or floral visitors of trees that provide these resources, often due to the difficulty of accessing tree canopies. This study addresses key knowledge gaps from a data poor region, providing information on the breeding systems and contribution of biotic pollination to two trees abundant in south-central Africa, that provide forest product supports for rural livelihoods: Julbernardia paniculata (Benth.) Troupin and Syzygium guineense (Willd.) subsp. barotsense F. White (Fabaceae and Myrtaceae respectively). The breeding systems of these species were assessed by conducting controlled pollination experiments, and then measuring the effects on reproductive success to determine the degree of self-compatibility and pollen limitation. Floral visitors and their behaviour were observed to provide preliminary information on possible pollinator groups. S. guineense appeared to be self-compatible, while J. paniculata showed signs of both self-incompatibility and pollen limitation. Floral visitors of both species were dominated by bees, with native honeybees (Apis mellifera) providing the highest visitation rates. These insights provide the first steps for understanding the reproductive ecology of these key tree species and can help to inform sustained management and conservation aimed at protecting forests and supporting rural livelihoods, as well as broaden the understanding of the floral visitors, and contribution of biotic pollination to forest tree reproductive success.

Reproductive Ecology and Bee Associates of Packard's Milkvetch (Astragalus packardiae), a Rare Plant Endemic to Southwestern Idaho

Reproductive Ecology and Bee Associates of Packard's Milkvetch (Astragalus packardiae), a Rare Plant Endemic to Southwestern Idaho

Care, Violence, and More-Than-Human Reproductive Ecologies in North India

ABSTRACT This paper explores therapeutic interventions for subfertility as a domain where meanings and boundaries of care and violence are constituted. It centres around a fragment of one Rajasthani woman’s reproductive journey contextualised within marriage migration, upward social mobility, and affinal/natal kin relations. Grounded in 18 months of ethnographic fieldwork in Rajasthan, India, and ongoing conversations with the family, this paper investigates therapeutic interventions undertaken by affinal and natal families—biomedical interventions alongside engagements with a Hindu goddess Kali—and examines how ambivalent care practices are situated within relations between people, technologies, and spirits who ‘meddle’ with human affairs. It argues that the meanings of care are constituted relationally within more-than-human reproductive ecologies.

Reproductive ecology of the black rat (Rattus rattus) in Madagascar: the influence of density-dependent and -independent effects.

The black rat (Rattus rattus) poses a severe threat to food security and public health in Madagascar, where it is a major cause of pre- and post-harvest crop losses and an important reservoir for many zoonotic diseases, including plague. Elsewhere, ecologically based rodent management (EBRM) strategies have been developed using ecological information to inform decisions on where and when to target control. EBRM could deliver improved health and well-being outcomes in Madagascar if adapted to the local ecological context. Using data collected from removal studies, we explored spatio-temporal patterns in the breeding activity of the black rat (R. rattus) in domestic and agricultural habitats across Madagascar and investigated to what extent these trends are influenced by rainfall and rat density. We identified clear spatio-temporal variation in the seasonality of R. rattus reproduction. Reproduction was highly seasonal both inside and outside of houses, but seasonal trends varied between these two habitats. Seasonal trends were explained, in part, by variation in rainfall; however, the effect of rainfall on reproductive rates did itself vary by season and habitat type. A decline in breeding intensity with increasing rat density was recorded outside of houses. This has important implications for control, as populations may compensate for removal through increased reproduction. We recommend that sustained control initiated before the main breeding season, combined with improved hygiene and adequate rodent-proofing in homes and grain stores, could curtail population growth and reduce pre- and post-harvest losses provided that these measures overcome the compensatory response of rodent populations.

Same-sex sociosexual behaviour is widespread and heritable in male rhesus macaques.

Numerous reports have documented the occurrence of same-sex sociosexual behaviour (SSB) across animal species. However, the distribution of the behaviour within a species needs to be studied to test hypotheses describing its evolution and maintenance, in particular whether the behaviour is heritable and can therefore evolve by natural selection. Here we collected detailed observations across 3 yr of social and mounting behaviour of 236 male semi-wild rhesus macaques, which we combined with a pedigree dating back to 1938, to show that SSB is both repeatable (19.35%) and heritable (6.4%). Demographic factors (age and group structure) explained SSB variation only marginally. Furthermore, we found a positive genetic correlation between same-sex mounter and mountee activities, indicating a common basis to different forms of SSB. Finally, we found no evidence of fitness costs to SSB, but show instead that the behaviour mediated coalitionary partnerships that have been linked to improved reproductive success. Together, our results demonstrate that SSB is frequent in rhesus macaques, can evolve, and is not costly, indicating that SSB may be a common feature of primate reproductive ecology.

Desmopsisterriflora, an extraordinary new species of Annonaceae with flagelliflory.

Flagelliflory refers to the production of inflorescences exclusively on long, whip-like branches which emerge from the main trunk and extend along the ground or below it. It is the rarest type of cauliflory and only a few cases have been reported in the world. Here, a new species of Annonaceae with flagelliflory is described and illustrated. The phylogenetic relationships of the new species were inferred using a hybrid-capture phylogenomic approach and we present some notes on its reproductive ecology and pollen characteristics. The new species, namely Desmopsisterriflorasp. nov., is part of a clade composed of Mexican species of Stenanona with long, awned petals. Desmopsisterriflora is distinguished by its flageliflorous inflorescences, basely fused sepals, thick red petals, reduced number of ovules per carpel, pollen grains with a weakly rugulate to fossulate exine ornamentation, and its globose, apiculate fruits with a woody testa. The morphological characteristics of the flagella suggest that these are specialized branches rather than inflorescences, and the absence of ramiflory implies an exclusively reproductive function. The flowers are infrequently visited by insects, their potential pollinators being flies and ants.

Репродуктивная экология бесхвостых амфибий: влияние внутренних и внешних факторов

This research paper examines the influence of internal factors (female body weight, body condition) and external ecological factors on the reproductive parameters of females, as well as on the reproductive ecology of adult individuals of anuran amphibians. Among the most significant reproductive characteristics of females are the number of eggs in a clutch, the proportion of reproductive products to female body weight (contribution to reproduction), and the average weight of eggs. The body weight of the female and the ecological (meteorological) conditions of her activity during the year preceding spawning, as well as the hibernation conditions, have the greatest impact on the quantitative expression of these parameters. The proportion of reproductive products to female body weight in anuran amphibians usually ranges from 13 to 30%. Climate warming can directly affect the reproductive parameters of females, the survival of metamorphs, and the phenology of the spawning period.

Pollinators limit seed production in an early blooming rare plant: evidence of a mismatch between plant phenology and pollinator emergence

The reproductive ecology of rare plants is seldom studied, yet the persistence of plant populations depends on successful mutualisms with pollinators. As atmospheric temperatures rise, phenology of plants and pollinators may become mismatched. We investigated the reproduction of Trifolium barnebyi (Barneby's clover), a mat‐forming perennial endemic to central Wyoming, USA, that grows in the crevices of sandstone bedrock. Our objectives were to evaluate a method for monitoring changes in cover as well as assess the pollination and seed‐set of T. barnebyi. We established five monitoring transects using a divided frame to estimate percent cover. We conducted seed‐set experiments at three locations to measure self‐pollination and the degree to which pollinating insects limited seed production. We used vane traps and bee bowls to capture pollinators, and examined pollen carried on bees. Percent cover along transects declined over the four year period and was associated with spring precipitation. Trifolium barnebyi did not self‐pollinate and relied on pollinators to produce seeds. The number and mass of viable seeds per flower, and the number of bees captured increased as the season progressed, indicating that more and larger seeds were made when more pollinators were present. Blooming of T. barnebyi ranged between April and June, depending on the microhabitat the plant lived in, and we observed much higher seed production in later‐blooming plants. Pollen from T. barnebyi was primarily carried by Andrena bees, although we found smaller amounts of pollen on seven other bee genera. A mismatch in timing between blooming and pollinating insect emergence could limit seed production in T. barnebyi if plants bloom earlier over time and bee emergence does not follow the same phenology. Rare plants can be pollinated by rare pollinators showing that conserving these pollinators is crucial for rare plants and early blooming species may be higher at risk.

Year-round spawning of three tropical Cypriniformes fishes in Southeast Asia

Present knowledge on spawning seasonality of freshwater fishes in tropical Asia and their relationship with environmental factors remains limited. Three Southeast Asian Cypriniformes fishes, Lobocheilos ovalis, Rasbora argyrotaenia and Tor Tambra, found in rainforest streams in Brunei Darussalam were studied on a monthly basis for a period of 2 years. To assess spawning characteristics, seasonality, gonadosomatic index and reproductive phases were examined from 621 L. ovalis, 507 R. argyrotaenia and 138 T. tambra. This study also examined environmental factors such as rainfall, air temperature, photoperiod and lunar illumination that may influence the timing of spawning of these species. We found that L. ovalis, R. argyrotaenia and T. tambra were reproductively active throughout the year but did not find that spawning in these species were associated with any of the investigated environmental factors. Our study showed that the non-seasonal reproductive ecology found in the tropical cypriniform species is distinctly different from that of temperate cypriniforms, which are known to follow spawning seasonality, suggesting an evolutionary adaptation to ensure their survival in an unstable environment. The reproductive strategy and ecological responses found in the tropical cypriniforms might be shifted in response to climate change scenarios in the future.

Phenotype-fitness relationships and pollen-transfer efficiency of five orchid species with different pollination strategies.

Deceptive pollination, a fascinating mechanism that independently originated in several plant families for benefiting from pollinators without providing any reward, is particularly widespread among orchids. Pollination efficiency is crucial in orchids due to the aggregated pollen in a pollinarium, which facilitates pollen transfer and promotes cross-pollination as pollinators leave after being deceived. In this study, we compiled data on reproductive ecology from five orchid species with different pollination strategies: three deceptive-strategy species (shelter imitation, food deception, sexual deception), one nectar-rewarding species, and one shelter-imitation but spontaneously selfing species. We aimed to compare the reproductive success (female fitness: fruit set; male fitness: pollinarium removal) and pollination efficiency of species representing these strategies. We also investigated pollen limitation and inbreeding depression among the pollination strategies. Male and female fitness were strongly correlated in all species but the spontaneously selfing species, which had high fruit set and low pollinarium removal. As expected, pollination efficiency was highest for the rewarding species and the sexually deceptive species. Rewarding species had no pollen limitation but did have high cumulative inbreeding depression; deceptive species had high pollen limitation and moderate inbreeding depression; and spontaneously selfing species did not have pollen limitation or inbreeding depression. Pollinator response to deception is critical to maintain reproductive success and avoid inbreeding in orchid species with non-rewarding pollination strategies. Our findings contribute to a better understanding of the trade-offs associated with different pollination strategies in orchids and highlight the importance of pollination efficiency in orchids due to the pollinarium.

Reproductive ecology of the soft-shell clam (Mya arenaria) in Eastern New Brunswick, Canada: Assessing size-at-maturity and spawning time to inform fisheries management

Soft-shell clams, Mya arenaria, are fished commercially and recreationally across much of their distribution. Several management measures have been implemented in Atlantic Canada to regulate the clam fishery, including a minimum legal size limit of 50 mm. This legal size limit, however, is not based on contemporary data. A regional understanding of soft-shell clam reproductive biology in eastern New Brunswick is lacking, yet the management of this fishery would greatly benefit from this localized knowledge. As such, we collected soft-shell clams in Kouchibouguac National Park, New Brunswick, Canada, during the Spring, Summer and Fall of 2021, to assess size-at-maturity and time of spawning. Histology was used to determine the sex and maturity stage of individual soft-shell clams and maturity ogives were generated for female and male clams. Temporal changes in the gonadosomatic index (GSI) were also used to identify likely spawning times for female and male clams. Sex ratios were significantly unbalanced for most of the sites sampled, favouring females, with an overall sex ratio of 2.3:1 (F: M). Size-at-maturity was estimated at 39.7 mm and 40.7 mm for female and male soft-shell clams, respectively. Overall, GSI was higher in males, peaking in late May, declining sharply in June, and showing a more gradual decline from July until September. Female GSI also peaked in late May, but exhibited a continuous, gradual decline from mid-June through to September, suggesting that peak spawning likely occurred from late May to mid-June in 2021 but that some degree of spawning likely continued thereafter. Overall, these results provide insights into the reproductive biology of sub-legal sized soft-shell clams in eastern New Brunswick, providing managers with contemporary scientific information.