Interpopulation Differences Research Articles

Comparative skin transcriptome analysis as a potential tool to investigate intra- and inter-population differences in belugas

Comparative skin transcriptome analysis as a potential tool to investigate intra- and inter-population differences in belugas

Relative facial width, and its association with canine size and body mass among chimpanzees and bonobos: Implications for understanding facial width-to-height ratio expression among human populations.

Facial width-to-height ratio (fWHR) has been widely investigated in the context of its role in visual communication, though there is a lack of consensus about how fWHR serves as a social signal. To better understand fWHR variation in a comparative context, we investigate the associations between fWHR and canine crown height (CCH) and body mass, respectively, among two chimpanzee subspecies (Pan troglodytes schweinfurthii, Pan troglodytes troglodytes) and bonobos (Pan paniscus). We collected landmark data from 3D surface models of 86 Pan cranial specimens to quantify fWHR and upper CCH, and to estimate body mass. We used Spearman's r and Kruskal-Wallis tests to test for significant relationships among variables, and to assess sexual dimorphism. There is an inverse relationship between fWHR and CCH in both sexes of Pan, however there are interpopulation differences in the relationship between fWHR and CCH among Pan taxa. Pan paniscus have relatively wide faces and small canine crowns, and wide faces in Pan t. schweinfurthii males may be driven by body size constraints. Pan troglodytes and Pan paniscus show fWHR dimorphism, and Pan paniscus have significantly higher fWHRs than do either Pan troglodytes subspecies. Our findings indicate that CCH and facial breadth may serve subtly different signaling functions among Pan taxa. Further research into the circumstances in which wide faces evolved among chimpanzees and bonobos will likely afford deeper insights into the function of relatively wide faces in the context of visual signaling among humans and our extinct hominin relatives.

Transcriptome-Wide Association Analysis of Flavonoid Biosynthesis Genes and Their Correlation With Leaf Phenotypes in Hawk Tea (Litsea coreana var. sinensis).

Hawk tea (Litsea coreana var. sinensis), derived from the tender shoots or leaves, rich in flavonoids can promote healthcare for humans. The primary flavonoid are kaempferol-3-O-β-D-glucoside, kaempferol-3-O-β-D-galactoside, quercetin-3-O-β-D-glucoside, and quercetin-3-O-β-D-galactoside. The existence of an association between leaf phenotype and flavonoid content, along with the underlying mechanisms of flavonoid biosynthesis, remains incompletely understood. In this study, 109 samples were analyzed to determine the correlation and genetic variability in leaf phenotype and flavonoid content. Furthermore, a transcriptome-wide association study identified candidate loci implicated in the biosynthesis of four key flavonoids. The study revealed that genetic variability in leaf traits and flavonoid concentrations is predominantly attributed to interpopulation differences. Flavonoid accumulation was significantly correlated with tree DBH, indicative of age-related traits. Transcriptome-wide association analysis identified 84 significant SNPs associated with flavonoid content, with only 13 located within gene regions. The majority of these genes are implicated in metabolic processes and secondary metabolite biosynthesis. Notably, structural genes within these regions are directly involved in pathways known to regulate flavonoid metabolism, exerting a pivotal influence on flavonoid biosynthesis. These results revealed the physiological basis for the regulation of flavonoid content, as well as the molecular mechanisms for the biosynthesis of flavonoids in hawk tea. It also lays theoretical groundwork for subsequent explorations into the genetic determinants influencing flavonoid accumulation of hawk tea.

Morphological variation of endemic Gymnocypris chilianensis (Cyprinidae) collected from three inland water systems in Qilian Mountains, China

To explore the morphological differences among different geographic populations of Gymnocypris chilianensis, 29 measurable traits and 13 landmarks on 191 individuals of 10 geographic populations were collected from three different inland water systems, i.e., Shiyang River, Heihe River, and Shule River, in Qilian Mountains, China. Multivariate statistical methods were used to compare morphological differences among the populations, such as principal component analysis, cluster analysis, discriminant analysis, and visual analysis of landmark data. The results showed that: (1) There were significant morphological differences between groups of G. chilianensis. The Shiyang River basin differs significantly from populations in the other two basins. (2) The inter-population differences were mainly reflected in the length of the trunk and tail, and the difference between trunk and caudal fin had the most obvious characteristics, proving the tail being the main direction of variation. This research provides an effective theoretical basis for the fine management and accurate protection of G. chilianensis germplasm resources.

A clinical protocol for a German birth cohort study of the Maturation of Immunity Against respiratory viral Infections (MIAI).

Respiratory viral infections (RVIs) are a major global contributor to morbidity and mortality. The susceptibility and outcome of RVIs are strongly age-dependent and show considerable inter-population differences, pointing to genetically and/or environmentally driven developmental variability. The factors determining the age-dependency and shaping the age-related changes of human anti-RVI immunity after birth are still elusive. We are conducting a prospective birth cohort study aiming at identifying endogenous and environmental factors associated with the susceptibility to RVIs and their impact on cellular and humoral immune responses against the influenza A virus (IAV), respiratory syncytial virus (RSV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The MIAI birth cohort enrolls healthy, full-term neonates born at the University Hospital Würzburg, Germany, with follow-up at four defined time-points during the first year of life. At each study visit, clinical metadata including diet, lifestyle, sociodemographic information, and physical examinations, are collected along with extensive biomaterial sampling. Biomaterials are used to generate comprehensive, integrated multi-omics datasets including transcriptomic, epigenomic, proteomic, metabolomic and microbiomic methods. The results are expected to capture a holistic picture of the variability of immune trajectories with a focus on cellular and humoral key players involved in the defense of RVIs and the impact of host and environmental factors thereon. Thereby, MIAI aims at providing insights that allow unraveling molecular mechanisms that can be targeted to promote the development of competent anti-RVI immunity in early life and prevent severe RVIs. https://drks.de/search/de/trial/, identifier DRKS00034278.

Telomere Length, HLA, and Longevity-Results from a Multicenter Study.

Aging is an exceptionally complex process that depends on genetic, environmental, and lifestyle factors. Previous studies within the International HLA and Immunogenetics Workshop (IHIWS) component "Immunogenetics of Ageing" showed that longevity is associated with positive selection of HLA-DRB1*11- and DRB1*16-associated haplotypes, shown to be protective against diseases. Within the 18th IHIWS, we aimed to investigate the relevance of telomere length for successful aging and its association with classical HLAs. In total 957 individuals from Bulgaria, Turkey, Romania, and Poland in two age groups, elderly individuals (age 65-99 years) and ethnically matched young group (age 18-64 years), were investigated. The obtained results confirmed interpopulation differences in the distribution of HLA alleles, documented the lengths of telomeres in analyzed populations, and demonstrated significant associations of telomere length with aging as well as with the presence of some HLA class I or class II alleles. They suggest that telomere length assessment combined with HLA genotyping may help identify immunogenetic profiles associated with longevity. The associations between HLA and telomeres support the theory that HLA genes influence the aging process. However, further research is needed to clarify the biological basis of the observed relationships.

Adipose development is consistent across hunter-gatherers and diverges from western references.

Despite agreement that humans have evolved to be unusually fat primates, adipose patterning among hunter-gatherers has received little empirical consideration. Here we consider the development of adiposity among four contemporary groups of hunter-gatherers, the Aka, Savanna Pumé, Ju'/Hoansi and Agta using multi-level generalized additive mixed modelling to characterize the growth of tricep skinfolds from early childhood through adolescence. In contrast to references, hunter-gatherers show several consistent patterns: (i) children are lean with little fat accumulation; (ii) no adiposity rebound at 5 years is evident; (iii) girls on average have built 90% of their body size, and reach menarche when adiposity is at its maximum velocity; and (iv) a metabolic trade-off is evident in young, but not older children, such that both boys and girls prioritize skeletal growth during middle childhood, a trade-off that diminishes during adolescence when height velocity increases in pace with fat accumulation. Consistent results across hunter-gatherers living in diverse environments suggest that these patterns reflect a general forager pattern of development. The findings provide a valuable baseline for adipose development not apparent from reference populations. We emphasize both generalized trends among hunter-gatherers, and that inter-populational differences point to the plasticity with which humans organize growth and development.

Resolving haplotype variation and complex genetic architecture in the human immunoglobulin kappa chain locus in individuals of diverse ancestry

Immunoglobulins (IGs), critical components of the human immune system, are composed of heavy and light protein chains encoded at three genomic loci. The IG Kappa (IGK) chain locus consists of two large, inverted segmental duplications. The complexity of the IG loci has hindered use of standard high-throughput methods for characterizing genetic variation within these regions. To overcome these limitations, we use long-read sequencing to create haplotype-resolved IGK assemblies in an ancestrally diverse cohort (n = 36), representing the first comprehensive description of IGK haplotype variation. We identify extensive locus polymorphism, including novel single nucleotide variants (SNVs) and novel structural variants harboring functional IGKV genes. Among 47 functional IGKV genes, we identify 145 alleles, 67 of which were not previously curated. We report inter-population differences in allele frequencies for 10 IGKV genes, including alleles unique to specific populations within this dataset. We identify haplotypes carrying signatures of gene conversion that associate with SNV enrichment in the IGK distal region, and a haplotype with an inversion spanning the proximal and distal regions. These data provide a critical resource of curated genomic reference information from diverse ancestries, laying a foundation for advancing our understanding of population-level genetic variation in the IGK locus.

Intraspecific variation in the functional response of an invasive crayfish under different temperatures

Non-native species can react to changes to their thermal environment by altering their feeding behaviour, thereby potentially causing shifts in predator–prey dynamics and competitive dominance over native species. In this study, we measured intraspecific variation in the functional response (i.e., predation rate as a function of prey density) of the rusty crayfish Faxonius rusticus (Girard, 1852) at two temperatures (18 °C and 26 °C) in the laboratory. We compared six invasive populations spanning a 2° latitudinal gradient in eastern North America to test the prediction that under warmer conditions individuals from more southerly populations exhibit a higher functional response than those from northern populations. Temperature, latitude, and the interaction between these two variables had significant effects on attack rates and handling times of individual crayfish from the tested populations. Contrary to our prediction, the attack rates of individuals from northern populations were consistently higher than those from southern populations at both temperatures. We propose that these interpopulation differences in functional response could arise, at least in part, from countergradient selection. Our results suggest that climate warming promotes spatiotemporal variation in per capita effects across latitudinally distributed populations of aquatic invasive species.

Enterobacteriaceae as a Key Indicator of Huanglongbing Infection in Diaphorina citri.

Extensive microbial interactions occur within insect hosts. However, the interactions between the Huanglongbing (HLB) pathogen and endosymbiotic bacteria within the Asian citrus psyllid (ACP, Diaphorina citri Kuwayama) in wild populations remain elusive. Thus, this study aimed to detect the infection rates of HLB in the ACP across five localities in China, with a widespread prevalence in Ruijin (RJ, 58%), Huidong (HD, 28%), and Lingui (LG, 15%) populations. Next, microbial communities of RJ and LG populations collected from citrus were analyzed via 16S rRNA amplicon sequencing. The results revealed a markedly higher microbial diversity in the RJ population compared to the LG population. Moreover, the PCoA analysis identified significant differences in microbial communities between the two populations. Considering that the inter-population differences of Bray-Curtis dissimilarity in the RJ population exceeded those between populations, separate analyses were performed. Our findings indicated an increased abundance of Enterobacteriaceae in individuals infected with HLB in both populations. Random forest analysis also identified Enterobacteriaceae as a crucial indicator of HLB infection. Furthermore, the phylogenetic analysis suggested a potential regulatory role of ASV4017 in Enterobacteriaceae for ACP, suggesting its possible attractant activity. This research contributes to expanding the understanding of microbial communities associated with HLB infection, holding significant implications for HLB prevention and treatment.

Lower extremity arterial disease vs. coronary artery disease: mortality differences after revascularization.

Patients undergoing revascularization for lower extremity arterial disease (LEAD) may face a higher risk of mortality than those with coronary artery disease (CAD). This study aimed to characterize the difference in mortality risk between patients undergoing revascularization for LEAD and CAD and identify associated factors. The 1-year database of 10 754 patients undergoing revascularization for CAD (n = 6349) and LEAD (n = 4405) was analysed. Poisson regression models were used to characterize interpopulation differences in mortality, adjusting for baseline clinical features, including age, sex, polyvascular disease, comorbidities, medications, and vulnerabilities. Individuals with LEAD were older, were more likely to have polyvascular disease, had more comorbidities, and received fewer cardioprotective drugs than those with CAD. Vulnerabilities remained more common in the LEAD group even after adjusting for these clinical features. The crude risk ratio of mortality incidence for LEAD vs. CAD was 2.91 (95% confidence interval, 2.54-3.34), attenuated to 2.14 (1.83-2.50) after controlling for age, sex, and polyvascular disease. The percentage attenuation in the excessive mortality associated with LEAD was 29%. The stepwise addition of comorbidities, medications, and vulnerabilities as adjusting factors attenuated the incidence risk ratio to 1.48 (1.26-1.72), 1.33 (1.12-1.58), and 1.17 (0.98-1.39), respectively, and increased the percentage attenuation to 64%, 73%, and 86%, respectively. Mortality risk was almost three-fold higher in patients undergoing revascularization for LEAD than in those with CAD. The excessive mortality was considerably attributable to inter-group differences in baseline characteristics, including potentially clinically or socially modifiable factors.

Taxonomic inflation as a conservation trap for inbred populations.

Conservation is prioritized based on accepted taxa. As a consequence, a conservation incentive exists to emphasize inter-population differences to define taxa, potentially leading to taxonomic inflation. But stressing the uniqueness of threatened populations has the side effect of hindering conservation actions that promote inter-population gene flow, such as genetic rescue. These actions may be of critical importance for severely inbred populations involved in extinction vortices, for which an inflated taxonomy can become a conservation trap. Here, we exemplify this scenario with the western capercaillie (Tetrao urogallus, Phasianidae) population in the Cantabrian Mountains, described and legally listed as a subspecies not supported by recent molecular data. The Cantabrian capercaillie population is Critically Endangered after a long-lasting decline and a recent demographic collapse. It shows clear signs of inbreeding depression, including striking clutch size decreases as well as reduced hatchability and chick survival. This critical situation could be alleviated through a genetic rescue, but this possibility is hindered by inertias rooted in the putative uniqueness of the Cantabrian capercaillie. It had been previously argued that poor taxonomy could hamper conservation, through the oblivion of populations deserving, but not having, a taxonomic status. We show that taxonomic inflation can also become an obstacle for effective conservation.

Resolving haplotype variation and complex genetic architecture in the human immunoglobulin kappa and lambda chain loci in individuals of diverse ancestry

Abstract Immunoglobulins (IGs), critical components of the human immune system, are composed of heavy and light protein chains encoded at three genomic loci. The IG Kappa (IGK) chain locus consists of two large, inverted segmental duplications. The complexity of IG loci has hindered effective use of standard high-throughput methods for characterizing genetic variation within these regions. To overcome these limitations, we leverage long-read sequencing to create haplotype-resolved IGK assemblies in an ancestrally diverse cohort (n=36), representing the first comprehensive description of IGK haplotype variation. We identify extensive locus polymorphism, including novel single nucleotide variants (SNVs) and a common novel ∼24.7 Kbp structural variant harboring a functional IGKV gene. Among 47 functional IGKV genes, we identify 141 alleles, 64 (45.4%) of which were not previously curated. We report inter-population differences in allele frequencies for 14 IGKV genes, including alleles unique to specific populations within this dataset. In addition, we identify haplotypes carrying signatures of gene conversion that associate with enrichment of SNVs in the IGK distal region. Finally, we identify extensive polymorphism in the IG Lambda (IGL) locus, including copy number variation for genes encoding IGLC and IGLJ genes. These data lay a foundation for advancing our understanding of how genetic variation in IG loci impacts expressed antibody repertoires in human populations.

Analysis of intra-specific variations in the venom of individual snakes based on Raman spectroscopy

The knowledge of variations in the composition of venoms from different snakes is important from both theoretical and practical points of view, in particular, at developing and selecting an antivenom. Many studies on this topic are conducted with pooled venoms, while the existence and significance of variations in the composition of venoms between individual snakes of the same species are emphasized by many authors. It is important to study both inter- and intra-specific, including intra-population, venom variations, because intra-specific variations in the venom composition may affect the effectiveness of antivenoms as strongly as inter-specific. In this work, based on venom Raman spectroscopy with principal component analysis, we assessed the variations in venoms of individual snakes of the Vipera nikolskii species from two populations and compared these intra-specific variations with inter-specific variations (with regard to the other related species). We demonstrated intra-specific (inter- and intra-population) differences in venom compositions which are smaller than inter-specific variations. We also assessed the compositions of V. nikolskii venoms from two populations to explain inter-population differences. The method used is rapid and requires virtually no preparation of samples, used in extremely small quantities, allowing the venoms of individual snakes to be analyzed. In addition, the method is informative and capable of detecting fairly subtle differences in the composition of venoms.

Polymorphisms of the ATP-binding cassette sterol efflux transporter genes g5 and g8 in cardiovascular diseases and type 2 diabetes mellitus

Mutations with a decrease in the expression and function of the of the ATP-binding cassette genes proteins ABCG5 and ABCG8, as the main sterol efflux transporters, lead to the accumulation of xenosterols in plasma associated with changes in the lipid profile, hyperglycemia and the risk of cardiovascular diseases (CVD) and type 2 diabetes mellitus (DM2). The review presents studies of the role of ABCG5/G8 polymorphisms in CVD and DM2. In several studies, including large–scale ones, the influence of ABCG5/G8 variants (rs4245791, rs41360247 rs4299376, rs11887534, rs7598542, rs78451356, etc.) on the risk of coronary heart disease (CHD) was proved, in others – when confirming the association of the risk of CHD with ABCG5 polymorphism, this status for ABCG8 was denied. Since sterol metabolism disorders observed in individuals with DM2 are probably associated with low insulin sensitivity, many authors confirmed the association of variants rs4299376, rs4148211, rs140231607 and rs6720173 of the ABCG5/G8 with the risk of DM2, but some authors did not find such a connection with DM2 for variants rs4299376, rs11887534 and rs4148217 of the ABCG8. A decrease in ABCG5/G8 mRNA expression was observed in DM2 in experimental animals and in humans; on the contrary, overexpression of ABCG5/G8 in db/db mice restored the sensitivity of the liver to insulin, which led to a decrease in fasting glucose, lipids and improved glucose tolerance. The inconsistency of data on the association of ABCG5/G8 gene polymorphism with the risk of CVD and DM2 may probably be due to inter-population differences, which necessitates further study of the contribution of ABCG5/G8 variants to the risk of these diseases.

Morphological divergence of domatia in ant-free populations of the widespread Neotropical myrmecophyte Miconia tococa (Melastomataceae)

Abstract Co-evolving organisms experience multiple selection pressures that may lead to trait mismatches among different populations and sites. In defensive ant–plant mutualisms, host plants (myrmecophytes) produce specialized shelters (domatia) to harbour specialized ant-partners in exchange for protection against enemies. Although populations of myrmecophytes without ants occur in some locations, there are no records of changes in domatia morphology—at the population level—due to the absence of symbiotic ants. We conducted broad-scale samplings of Miconia tococa (Melastomataceae) populations across the Brazilian Cerrado and a 2-year transplant experiment to test whether domatia morphology changes when symbiotic ants are naturally absent. Domatia were 33.9% smaller in ant-free populations than in ant-inhabited populations. Transplants revealed that host plants from ant-inhabited sites still developed larger domatia than those from ant-free sites, even in the absence of ant-partners. These findings point to a change of M. tococa traits associated with biotic defences where symbiotic ants are absent. What may have begun as a plastic adjustment to ant-free environments appears to have been transformed into fixed (genetic) interpopulation differences over time, indicating a potential local destabilization of the mutualism or a mechanism to stabilize the interaction at the landscape scale.

Redescription of Xiphinema artemisiae Chizhov, Tiev & Turkina, 1986 (Dorylaimida: Longidoridae): new occurrence in Iran

Summary A population of Xiphinema artemisiae was recovered from Iran, representing the first report after its original description from a meadow pasture in northern Caucasus, Russia. The Iranian population was recovered from the rhizosphere of grasses in the Damavand region, Tehran province. The females of the recovered populations are characterised by a lip region separated from the rest of body by a depression, a 5.1-5.6 mm long body, a 129-138 μm long odontostyle, 76-85 μm long odontophore, a uterus having a pseudo-Z-organ and crystalloid bodies observed in some specimens, and a short, rounded, dorsally more convex tail with a subcentral mucron, four juvenile developmental stages (the first stage was not recovered) and functional males. The Iranian population is morphologically and morphometrically similar to the type population and minor morphological differences can be attributed to geographical interpopulation differences. Molecular phylogenetic relationships of the Iranian population of X. artemisiae with other species were reconstructed using sequences of three genomic ribosomal markers, viz. small, large subunit D2-D3 and internal transcribed spacer (SSU, LSU D2-D3 and ITS) rDNA.

Deciphering induced variability, character association and multivariate analysis utilizing gamma rays and ethyl methanesulfonate in bread wheat (Triticum aestivum L.) genotypes with differential grain texture

Purpose Sustainable wheat production and higher genetic gains can be realized by broadening the genetic base and improving the well adapted varieties. In the present study, a multi-year experiment involving induced mutagenesis was conducted to create genetic variation, assess trait associations and genetic divergence in four wheat varieties with differential grain texture treated with six doses of gamma rays and ethyl methane sulfonate using ten agro-morphological traits. Materials and methods Healthy selfed seeds of four bread wheat varieties with differential texture were irradiated using six doses ranging from 175 Gy-300 Gy of gamma rays (Co60: BARC, Mumbai) and six concentrations of ethyl methanesulfonate (0.3–1.3%) (Sigma-Aldrich, Bangalore, India) to evaluate variability, character association and degree of genetic diversity induced among the mutagenic treatments of wheat varieties with differential grain texture. Results Significant inter-population differences were observed for almost all the traits. The sample mean of twelve mutant populations in each of the cultivar exhibited superior quantitative phenotypic traits and increased values of the genetic parameters. Based on association and variability studies, plant height, spike length, grain filling period, biological yield per plant and harvest index can be used as early generation criteria for maximum genetic improvement. Multivariate studies indicated the contribution of various traits towards divergence and indicated the efficiency of mutagens in generating variability. Gamma-irradiation dosages between 200–250 Gy and 0.5–1.1% EMS for soft-textured varieties, whereas doses between 225–275 Gy and 0.5–0.9% EMS were found to be most potent for semi-hard-textured varieties. Conclusions Assessment of mutagen sensitivity showed that semi-hard wheat varieties were responsive to both mutagens, particularly EMS and generated higher variability and divergence than the soft textured varieties. Hence, gamma rays were proved to be more effective in generating higher variability than ethyl methanesulfonate. A total of 117 putative mutants were identified with desirable agro-morphological attributes. Among these, mutants with higher inter-cluster distance can be used as parents in hybridization programs and serve as important genetic resources in future wheat improvement programs.

Variation of the chemical and biochemical responses to salinity during germination and early growth of seedlings of two populations of Agave durangensis Gentry

Agave durangensis (Asparagaceae) sustains a mescal industry in Mexico. The main reproductive strategy of the species is by seeds. The increased demand for agave-based beverages encourages producers to seek new cultivation areas. However, more than half of the territory of the country includes arid and semiarid zones, which are highly affected by salinity. The aim of the current study was to determine if salinity triggers different seed germination potential and variable biochemical and chemical responses in seedlings of two populations of A. durangensis, that might confer different tolerance to salinity. Seeds from each population were irrigated with four salinity treatments. Germination potential, as well as growth parameters and biochemical and chemical attributes of seedlings, were determined. Although with reduced germinability and germination speed, seeds of the two populations were able to germinate even under the strongest NaCl concentration (100 mM) evaluated. Effects in the growth parameters were registered; however, the seedlings of both populations survived throughout the experiments, increasing chlorophyll content and cell viability in most saline treatments. The enzymatic defense mechanism and the accumulation of proline were activated in a salt-dependent manner, which did not occur with the phenolic compounds; however, monomeric anthocyanin accumulation was outstanding under the two strongest NaCl concentrations evaluated. Important interpopulation differences were registered in each type of response, which were differently regulated under variable NaCl concentrations, some of them being more important than others under a particular saline condition. Seeds from the population Durango were more sensitive to salinity.

Feeding behaviour and food choice in three populations of the millipede Glomeris hexasticha Brandt, 1833 (Diplopoda: Glomerida: Glomeridae): intra- and interpopulation laboratory study

Abstract Foraging behaviour, determined by both internal and external factors, requires investment of time and energy. Optimizing the nutritional decisions also influences efficiency during the feeding process and fitness. Feeding behaviour has been poorly investigated in millipedes. Hence, the aims of this study were to test food choice and to explore intra- and interpopulation variability in several sequences of feeding behaviour in millipede Glomeris hexasticha Brandt, 1833 under laboratory conditions. Individuals of G. hexasticha and leaf litter were collected from three populations within Belgrade, Serbia. A feeding experiment was conducted using a cross-shaped experimental maze with oak leaves, small-leaved linden leaves, and moss as potential food sources. The individuals most often chose oak leaves, subsequently moss, while linden leaves were the least preferred. Sexual dimorphism was detected only for the average time spent in maze arms that contained food items in the Ada New Belgrade population and the Hyde Park population. Intrapopulation differences that depended on feeding status and interpopulation differences in some behavioural sequences were detected. We assume that sexual dimorphism in most of the analysed behavioural traits was not detected, because both sexes had to satisfy basic nutritive requirements after the same starvation period. However, research timing may be responsible, at least partially, for the obtained results. Repeating experiments in different periods of the year or using more fresh food or food sources in different phases of the decomposition may give different results. Further, in our experimental design, some unknown preference towards particular maze arms could not be completely excluded.