The Science of Nature最新文献

Embedded in the tail base of all snakes is a pair of scent glands from which typically foul-smelling secretions are expelled when snakes are disturbed. The tendency of predatory ants to avoid snake cloacal fluids, and the abundance and structural diversity of potentially insecticidal carboxylic acids identified in scent gland secretions (SGS), prompted speculation that SGS function to deter ants. We examined the deterrent properties of the SGS of the Middle American burrowing python (Loxocemus bicolor) in fumigation, repellency, and contact-toxicity behavioral assays against workers of the red imported fire ant (Solenopsis invicta) and a species of carpenter ant (Camponotus floridanus), thus representing the two major ant sub-families, Myrmicinae and Formicinae, respectively. We also examined responses by S. invicta to the SGS of representative booid, pythonid, colubrine, elapinine, and crotaline snakes. None of the SGS samples affected the two ant species in fumigation tests. However, in repellency bioassays, ants given a choice between a droplet of water or sugar water versus a diluted droplet of SGS overwhelmingly avoided the latter, typically exhibiting rapid antennation from within a few mm, then retreating. Pure or diluted SGS applied directly to ants induced a high percentage of paralysis and death. Some treated ants exhibited symptoms of contact toxicosis but recovered within a 4-h observational period. Our results and reports of the responses of predatory ants to the Texas blindsnake (Rena dulcis) point to the scent glands as an ancient and widespread source of ant deterrents.

Phenology investigates the periodicity of biological events related to plant growth. There is limited phenological information on ferns, particularly under disturbance conditions such as forest edges and fire. This study aimed to identify phenological patterns and responses to environmental factors and post-accidental fire events, including leaf production and mortality, and the number of leaves of Cyathea mexiae Copel. at the edge of a semi-deciduous seasonal remnant of the Atlantic Forest in Brazil. Twenty-four plants were monitored for 22 months, with 10 of them affected by fire. We quantified and compared leaf number, production, and mortality, and evaluated their relationships with environmental factors (rainfall, temperature, and humidity), considering two groups: burned and unburned. Trunk height was measured and related to phenological events. Only one plant died post fire. Burned and unburned groups showed no significant differences in trunk height, leaf number, production, or mortality. Both groups exhibited discontinuous and irregular leaf production and mortality patterns. Both groups produced leaves immediately post fire, though with differences in peak timing. Burned plants displayed a rapid peak in leaf production (September), earlier than the peak in unburned plants (November). Only leaf mortality in unburned plants was positively correlated with rainfall and humidity. This study demonstrated a rapid recovery in leaf numbers following accidental fire for C. mexiae. The study revealed non-seasonal trends in the leaf production patterns of C. mexiae, with fire potentially inducing leaf mortality, reducing the sensitivity of this phenophase to environmental factors, and altering the timing of peak leaf production between the groups.

Hairy roots can be used in various fields of biotechnology, environmental protection, and agriculture, as well as for basic research. One of the actively developing areas is the use of hairy roots in pharmacy industry. The creation of collections of genetically transformed roots is of great practical importance. The collection of general focus includes specimens of different taxonomy, biological status, and geographical origin, which can be maintained in natural or artificial conditions of given country or region. The greatest interest is given by using genetically transformed roots of rare plant species, as it may allow to reduce exploitation of such plants in the wild. A pharmacological collection is necessary for the conservation and study of medicinal plants. The use of a collection of genetically transformed roots allows us to conduct research with various plant species and select the most promising genetically transformed roots for use as promising raw materials for the pharmaceutical and cosmetic industries, as well as in environmental protection, agriculture and for various studies in the field of biotechnology and plant physiology. The aim of the work was to methodology for the development of collections of hairy roots.

Evaluations of vegetative and reproductive phenology have yielded significant insights into how biotic and abiotic factors affect the phenological rhythms of plants and the impact of climate change on ecosystems. The aim of this study was to characterize the phenological patterns of vegetative growth, flowering, and fruiting of H. amargosensis and H. stellata in Atlantic Forest fragments, analyzing their relationships with climatic variables and pollinators. Periodic visits were made to the forest fragments where H. amargosensis and H. stellata are found to observe the development of the plants at each development stage. Hohenbergia amargosensis flowered every two years (supra-annual flowering), while H. stellata did so annually. Both species reproduced both asexually and sexually, and their phenophases were seasonal, except for the emission of young leaves by H. stellata. Eight pollinator species and two robbers were recorded in H. amargosensis, while four pollinator species and one robber were recorded in H. stellata. The main pollinating agents were hummingbirds (Trochilidae) and bees (Apidae). The data obtained on the phenology aspects of Hohenbergia species and their pollinators are important to support studies aiming the conservation of these species.

Research on the diversity of bacterial communities and their influencing factors in the sediments of the Bohai Sea remains limited. This study used high-throughput sequencing technology to explore the vertical distribution characteristics and influencing factors (depth, heavy metals, and nutrients) of bacterial communities in sediment core B18 from the Bohai Sea. Our results indicated that the dominant phyla were Proteobacteria, Desulfobacterota, Acidobacteriota, Chloroflexi, Bacteroidota, and Actinobacteriota, with Alphaproteobacteria, Gammaproteobacteria, Bacteroidia, Anaerolineae, Thermoanaerobaculia, and Desulfobulbia as the dominant classes. Depth exerted a pronounced influence on bacterial community diversities, with bacterial communities (excluding Proteobacteria, Bacteroidota, and Verrucomicrobiota) displaying a positive correlation with depth. Anaerobic bacteria like Desulfobacterota and Chloroflexi were more prevalent in the deeper sediment layers. In contrast, most bacterial communities exhibited a negative relationship with heavy metal concentrations. Notably, As, Pb, and Cd contents exhibited relatively high levels of pollution and had a considerably negative effect on bacterial diversity. Bacterial communities with adaptability to heavy metals (such as Proteobacteria, Bacteroidota, Verrucomicrobiota) demonstrated a competitive advantage in the Bohai Sea sediment bacterial community compositions. Meanwhile, bacterial communities related to nitrogen, phosphorus, and sulfur cycling (Proteobacteria, Bacteroidota, Verrucomicrobiota) were relatively abundant. This study offers valuable insights into the diversity and compositions of bacterial communities in the Bohai Sea sediment profile by elucidating the vertical distribution and influencing factors of sediment bacterial communities.

Traversodontidae is a clade of non-mammaliaform cynodonts within the Cynognathia lineage, representing the most successful herbivorous/omnivorous group of the Triassic period. Here, we describe bony injuries in the ribs of a ~ 228–million–year–old traversodontid from Brazil. The specimen, assigned to Exaeretodon riograndensis, was discovered in Upper Triassic strata of the Santa Maria Supersequence, Paraná Basin. Macroscopic analysis, supported by micro-computed tomography, revealed the presence of bony calluses in the ribs, indicative of a transverse traumatic fracture, likely caused by a fall or an interaction (either intra- or interspecific) during the individual’s lifetime. Such trauma would have likely hindered its locomotion, impacting foraging efficiency and predator evasion. However, this species was possibly gregarious, which may have helped mitigate the injury’s impact on survival through group behavior. This finding represents a rare documented case of paleopathology in non-mammaliaform cynodonts, contributing to discussions on their behavior and paleoecology during the Triassic.

Many insects have symbiotic microorganisms within their body. Such microbial symbiosis underpins the survival and prosperity of insects through multiple means. The brown-winged green stinkbug Plautia stali, which is notorious as an agricultural pest and utilized as an experimental model insect, harbors a bacterial symbiont Pantoea in a posterior part of the midgut, which is essential for the host’s development and reproduction. From both basic and applied research perspectives, it is important to investigate the mechanistic bases underpinning the insect-microbe symbiotic association. Here, we performed detailed electron and optical microscopic analyses of the early nymphal midguts to reveal the type of cellular structure and property that orchestrates the symbiont colonization in the restricted part of the midgut. We identified two peculiar structural features of the nymphal midgut that develop in a region-restricted manner: long and heterogenous cellular protrusions (microvilli) solely emerged in the midgut symbiotic region and highly developed circular muscle cell layers specifically observed in the junction of non-symbiotic and symbiotic regions of the midgut. We discuss the potential roles of these unique structures in the midgut bacterial symbiosis.

Three new species, Antiquanabittacus punctatus Yu, Ren, Lin and Yang sp. nov., Composibittacus retroflexus Yu, Ren, Lin and Yang sp. nov. and Formosibittacus multifarius Yu, Ren, Lin and Yang sp. nov., with special wing spots are described and assigned to Bittacidae, based on well-preserved specimens from the Middle Jurassic of China. Antiquanabittacus punctatus sp. nov., the earliest fossil record of Antiquanabittacus, shows new genital characteristics that enhance our understanding of the early morphology of hangingflies. Two morphological types of wing spots are categorized by summarizing all fossil records of Bittacidae, which can be beneficial to classifications and identifications in species level. Wing spots of Type 1, disturbing the overall outline of insect body, and wing spots of Type 2, simulating the spots of light through leaves, may be conducive to conceal hangingflies from predators and improve their capability to ambush preys.

Parental care in nature can present itself in different forms and vary in intensities and strategies, being maternal care one of the widely observed patterns in animals. In spiders, parental investment is carried out mainly by females. Despite this, newly hatched eggs can still be targets of a series of natural enemies. In a remnant of Atlantic Forest in Brazil, females of the spider Eldar galadrielae sp. nov., family Anyphaenidae, build nests at the forest’s edge by folding plant leaves. However, information about the plants chosen for nest, the importance of maternal care by females in offspring survival, and predators are completely unknown. In this study, we (1) presented new information about the nest built by females of Eldar galadrielae sp. nov.; (2) compared the predation rate on eggs of the spider Eldar galadrielae in nests with and without the presence of the female; (3) provided morphological descriptions and distribution maps to the genus Eldar gen. nov. as well as presenting; and (4) the described Pseudogaurax vasconcellosi sp. nov. as the predator of the spider eggs. This is the first report on an interaction between Pseudogaurax flies and Anyphaenidae spiders. Our results support predation rates higher in female-less Eldar galadrielae sp. nov. nests. Although egg consumption was 100% in nests attacked by flies, overall nest predation rate was low, as flies were only recorded in three of the 12 nests that maintained female care, indicating that active protection of egg sacs by females can increase the offspring’s chances of survival.

The activity of six essential oils was investigated against eight fungal isolates (four Aspergillus and four Penicillium species) isolated from cultural heritage conservation premises in Serbia. To analyze the chemical composition of essential oils (EOs), gas chromatography coupled with mass spectrometry was employed. The antifungal activity of selected EOs was investigated using microdilution and microatmosphere methods while the commercial biocide benzalkonium chloride (BAC) was used as a control. Furthermore, molecular docking was used as an efficacious in silico method for the determination of interaction between dominant EO compounds and enzyme CYP51, essential for fungal ergosterol synthesis. It was demonstrated that BAC, Cinnamomum zeylanicum, and Gaultheria procumbens EOs had the strongest antifungal activity, which is in concordance with the results of molecular docking. Namely, the highest energy of enzyme–cofactor interaction was obtained for eugenol (the dominant component of Syzygium aromaticum and C. zeylanicum EOs). Moreover, it was found that the most resistant fungal isolates were A. flavus and A. niger, while A. sydowii and P. citrinum were the most susceptible. The results of our study point to the possibility of using studied environmentally friendly biocides of biological origin for the preservation of historical monuments and artifacts.