Early Life Stages Research Articles

Anomalous ocean currents and European anchovy dispersal in the Iberian ecosystem

Unlike other upwelling areas where sardine and anchovy species dominate the pelagic ecosystems, the Western Iberian ecosystem has been consistently dominated by European sardine Engraulis encrasicolus, while anchovy had a residual presence from the start of acoustic surveys, in 1989, to 2014. Since 2015, the abundance of anchovy in the Western Iberian margins has sharply increased and continues to show an increasing trend as of 2023. It is unclear if this increase is a result of dispersal from nearby recruitment areas, higher survival rates of early life stages due to favorable environmental conditions, or both. We used a set of different models to simulate the dispersion and survival of anchovy early life stages in the Iberian region for the years preceding the increase in anchovy abundance. An ocean model simulation with the model CROCO provided the fields used as background for Lagrangian simulations coupled to an individual-based model of anchovy eggs and larvae. We simulated the years 2013-2015, and the results show that in 2014 and 2015, anomalous upper-ocean circulation patterns with strong and persistent westward currents transported a large number of eggs and larvae from the Bay of Biscay (BoB) westward along the Northern Iberian margin. The maximum transport occurred in June and July 2015, when 8 and 4%, respectively, of the eggs spawned in the BoB potentially reached the Iberian west coast as larvae. This process might explain the increase in anchovy abundance in the Western Iberian ecosystem. The results of the study show that episodes of anomalous intense ocean currents, when coincident with high presence of eggs, can lead to the colonization of new areas, and connectivity between areas varies dramatically with time.

Early life stages of the snapping shrimp Alpheus cf. packardii: morphological description of the first three zoeal stages

ABSTRACT The morphology of the zoeae I, II and III of Alpheus cf. packardii was described based on laboratory-hatched larvae. Parental female was captured at Ubatuba bay, north coast of São Paulo, Brazil. The morphological characteristics of the species were compared with descriptions of other Alpheus species with known first zoeal stages. The zoea I of A. cf. packardii differs from the other 27 species through: coxal endite of maxillule with 6 (4 simple, and 2 sparsely plumose) setae; basal endite with 2 stout spines, 1 small plumose setae and 1 small simple setae; coxal endite of maxilla not bilobed, with 2 long sparsely plumose setae; basal endite bilobed, proximal lobe 2 simple and 1 sparsely plumose setae, distal lobe with 2 simple setae and 1 sparsely plumose setae, both with one terminal protuberance; second maxilliped with endopod 4-segmented, 1 terminal simple, 0, 1 terminal serrate, 5 (1 proximal and 3 terminal simple, plus 1 terminal serrate) setae. Considering the importance of the identification of larval forms in the natural environment, our results can be used in a larval identification key and help to advance research on areas such as ecological distribution of early post-embryonic stages in the meroplankton community.

Physical activity initiated from midlife on risk of dementia and cognitive impairment: The Health and Retirement Study.

Physical activity is associated with lower risk of dementia and cognitive impairment, but existing randomized controlled trials have shown conflicting results. As cognitive decline occurs decades before the onset of dementia, physical activity interventions initiated in late life may have missed the potential window for prevention. An ideal trial of physical activity initiated from midlife and lasts till incident dementia and cognitive impairment in late life is not feasible. We aimed to estimate the effectiveness of a hypothetical physical activity intervention initiated from midlife on reducing dementia and cognitive impairment by emulating target trials using observational data. The Health and Retirement Study was used to emulate target trials among noninstitutionalized participants aged 45 to 65 years with normal cognition who were physically inactive in the previous 2 years. Cognitive status was determined based on Langa-Weir classification of cognitive function (including immediate and delayed word recall tests, serial sevens subtraction, counting backward). Individuals were categorized as initiating physical activity or not, based on the self-reported physical activity. Intention-to-treat and per-protocol analysis were conducted with pooled logistic regression models with inverse-probability of treatment and censoring weights to estimate risk ratios (RRs), and 95% confidence intervals (95% CIs) were calculated with 200 sets of bootstrapping. Among 1505 participants (average age 57.6 ± 4.8 years, 67% women, 76.5% White), 72 cases of dementia and 409 cases of cognitive impairment occurred. After 12 years of follow-up, physical activity reduced dementia (RR = 0.70, 95% CI: 0.43, 0.99) for intention-to-treat analysis, and reduced dementia (RR = 0.51, 95% CI: 0.19, 0.99) and cognitive impairment (RR = 0.77, 95% CI: 0.61, 0.92) for per-protocol analysis. No significant reduction was found among older adults. Physical activity initiated during midlife may reduce dementia and cognitive impairment in late life, which highlights the importance of preventing cognitive outcomes at an earlier stage of life.

Impact of nutrition on hearing loss.

The incidence of hearing disorders is rising at an alarming rate, aggravated by increasing longevity, without sufficient social awareness and attention from public health officials. The etiology of hearing loss (HL) is multifactorial, including both genetic and environmental factors, such as noise, ototoxic drugs, and nutritional status. Therefore, it is necessary to expand knowledge about the relationship between the different factors involved as a first step towards prevention and potential repair of hearing damage before it becomes irreversible and significantly limits the quality of life. Our recent studies have demonstrated the interrelationship between nutrition and HL highlighting the strong need to implement prevention and nutritional intervention strategies aimed at promoting hearing health from the earliest stages of life.

Agricultural Pesticide-Induced Physiological Stresses in Freshwater Fishes of Bangladesh

In Bangladesh, most croplands are situated in floodplains, enriched by numerous rivers and extensive freshwater wetlands. These areas also support productive open-water fisheries, crucial for supplying protein, generating income, creating jobs, and boosting the GDP. However, the widespread use of pesticides in these floodplains to protect crops and enhance food production leads to significant environmental issues. Agricultural pesticide residues enter water bodies through runoff, rainwater, drainage, seepage, and spray drift, contaminating natural water bodies and exerting continuous stress on aquatic life, including fish. Previous studies have detected pesticide residues in surface waters, sediments, and fish in Bangladesh, posing a major threat to wetland ecosystems. Research on freshwater fish species in Bangladesh has highlighted toxic effects on fish gonads, such as adhesion, inter-follicular space degeneration, ovigerous lamellae degeneration, necrosis, degenerated perinucleolar oocytes, cytoplasmic retraction in ovaries, and damage to sertoli cells. Additional observed effects include irregularly shaped seminiferous tubules, breakage of seminiferous tubules, and empty lumens in testes. Pesticides also inflict harm on other internal organs of fish, with gill effects like clubbing, reduction of gill filaments, telangiectasia of gill lamellae, hemorrhage, and damage to gill rakers. Kidney and liver damage include necrosis, cellular tissue degradation, acute cellular swelling, and irregular renal corpuscles, along with autolysis, vacuolation, and fatty changes in the liver. Developing embryos and larvae of freshwater fish are particularly vulnerable to the toxic effects of agro-pesticides. Studies reveal acute toxicity during early life stages, evidenced by deformities like edema, notochord deformity, caudal fin damage, yolk sac damage, posterior region damage, tissue fragmentation, black pigmentation on the yolk, body curvature, and lordosis in larvae. Exposed embryos exhibit deformities such as dark brown yolk sacs, notochord deformities, and broken eggshells. Mortality rates of fish embryos and larvae escalate with higher pesticide concentrations in water. Haemato-biochemical parameters serve as crucial indicators of pesticide exposure in fish studies, showing alterations in blood hemoglobin, glucose, RBC, WBC counts, and various erythrocytic abnormalities like twin cells, fusion, echinocyte formation, spindle-shaped, tear-drop, and elongated cells. Nuclear abnormalities include binucleated cells, nuclear buds, nuclear bridges, karyopyknosis, and notched nuclei. Research suggests that even at low concentrations, agro-pesticides disrupt physiological functions and life history traits of fish, adversely impacting the natural productivity and biodiversity of freshwater fish in Bangladesh.

The Young and the Resilient: Investigating Coral Thermal Resilience in Early Life Stages.

Global ocean warming is affecting keystone species distributions and fitness, resulting in the degradation of marine ecosystems. Coral reefs are one of the most diverse and productive marine ecosystems. However, reef-building corals, the foundational taxa of coral reef ecosystems, are severely threatened by thermal stress. Models predict 40-80% of global coral cover will be lost by 2100, which highlights the urgent need for widespread interventions to preserve coral reef functionality. There has been extensive research on coral thermal stress and resilience, but 95% of studies have focused on adult corals. It is necessary to understand stress during early life stages (larvae, recruits, and juveniles), which will better inform selective breeding programs that aim to replenish reefs with resilient stock. In this review, we surveyed the literature on coral thermal resilience in early life stages, and we highlight that studies have been conducted on relatively few species (commonly Acropora spp.) and in limited regions (mainly Australia). Reef-building coral management will be improved by comprehensively understanding coral thermal resilience and fitness across life stages, as well as in diverse species and regions.

Unraveling dispersal of a coastal fish species in the juvenile life stage in the Yellow Sea using otolith chemistry

Dispersal is a critical process in marine ecology, with profound implications for population conservation and fisheries management. Previous research has predominantly focused on reef-associated species, but studying the dispersal of more mobile fish species in nearshore environments is exceptionally challenging due to the complex coastal hydrography similar to reefs, and therefore dispersal knowledge of some coastal migratory behavior fish remains preliminary. In this study, we investigated the dispersal of a coastal fish species (small yellow croaker Larimichthys polyactis) in its juvenile life stage using otolith elemental fingerprints. We aimed to investigate the dispersal patterns of juveniles with otolith chemistry and identify potential natal sources. Results indicated that (1) significant geographical variations in the otolith elemental signatures can be considered as natural markers for assessing fish dispersal; (2) although small yellow croakers in the juvenile life stage are capable of settlement, a significant proportion of individuals continue subsequent passive dispersal; (3) juveniles may have originated from 2 natal sources in the sampling areas based on the differences in the near-core chemistry fingerprints. Results demonstrate the applicability of otolith chemistry fingerprints as natural tags in coastal waters and suggest that juveniles with the ability to settle will still employ dispersal strategies. This study contributes to research on fish dispersal in the early life stage and has significant implications for the marine fishery management of small yellow croaker.

Integrated Metagenomic and Metabolomics Profiling Reveals Key Gut Microbiota and Metabolites Associated with Weaning Stress in Piglets.

(1) Background: Weaning is a challenging and stressful event in the pig's life, which disrupts physiological balance and induces oxidative stress. Microbiota play a significant role during the weaning process in piglets. Therefore, this study aimed to investigate key gut microbiota and metabolites associated with weaning stress in piglets. (2) Methods: A total of ten newborn piglet littermates were randomly assigned to two groups: S (suckling normally) and W (weaned at 21 d; all euthanized at 23 d). Specimens of the cecum were dehydrated with ethanol, cleared with xylene, embedded in paraffin, and cut into 4 mm thick serial sections. After deparaffinization, the sections were stained with hematoxylin and eosin (H&E) for morphometric analysis. Cecal metagenomic and liver LC-MS-based metabolomics were employed in this study. Statistical comparisons were performed by a two-tailed Student's t-test, and p < 0.05 indicated statistical significance. (3) Results: The results showed that weaning led to intestinal morphological damage in piglets. The intestinal villi of suckling piglets were intact, closely arranged in an orderly manner, and finger-shaped, with clear contours of columnar epithelial cells. In contrast, the intestines of weaned piglets showed villous atrophy and shedding, as well as mucosal bleeding. Metagenomics and metabolomics analyses showed significant differences in composition and function between suckling and weaned piglets. The W piglets showed a decrease and increase in the relative abundance of Bacteroidetes and Proteobacteria (p < 0.05), respectively. The core cecal flora in W piglets were Campylobacter and Clostridium, while those in S piglets were Prevotella and Lactobacillus. At the phylum level, the relative abundance of Bacteroidetes significantly decreased (p < 0.05) in weaned piglets, while Proteobacteria significantly increased (p < 0.05). Significant inter-group differences were observed in pathways and glycoside hydrolases in databases, such as the KEGG and CAZymes, including fructose and mannose metabolism, salmonella infection, antifolate resistance, GH135, GH16, GH32, and GH84. We identified 757 differential metabolites between the groups through metabolomic analyses-350 upregulated and 407 downregulated (screened in positive ion mode). In negative ion mode, 541 differential metabolites were identified, with 270 upregulated and 271 downregulated. Major differential metabolites included glycerophospholipids, histidine, nitrogen metabolism, glycine, serine, threonine, β-alanine, and primary bile acid biosynthesis. The significant differences in glycine, serine, and threonine metabolites may be potentially related to dysbiosis caused by weaning stress. Taken together, the identification of microbiome and metabolome signatures of suckling and weaned piglets has paved the way for developing health-promoting nutritional strategies, focusing on enhancing bacterial metabolite production in early life stages.

How and When Does Early Home Learning Environment Improve Children’s Kindergarten Academic Skills? The Roles of Language Ability and Self-Control

ABSTRACT Children’s academic skills, particularly in the early stages of life, are significantly shaped by the support and resources available in their home learning environments. However, the underlying mechanisms by which the home learning environment influences children’s academic skills are not fully understood. To address this gap, the present study used multiple regression analysis to explore how the family environment of U.S. children (N = 805) at 36 months old affected their academic skills at 5 years old. The result showed that children’s language ability may potentially serve as a mediating mechanism that links the home learning environment and children’s early academic skills. Furthermore, the study suggests that children’s self-control provides an important mechanism that moderates the relationship between the home learning environment and children’s language ability. The findings provide compelling new insights into how and when the home learning environment affects children’s early-stage academic skills.

Modelling the multiple action pathways of projected climate change on the Pacific cod (Gadus macrocephalus) early life stages

Understanding how future ocean conditions will impact early life stages and population recruitment of fishes is critical for adapting fisheries communities to climate change. In this study, we incorporated projected changes in physical and biological ecosystem dynamics from an oceanographic model into a mechanistic individual-based model for larval and juvenile stages of the Pacific cod (Gadus macrocephalus) in the eastern Bering Sea. We particularly investigated the impacts of ocean currents, temperature, prey density, and pCO2 on the hatching success, growth, survival, and spatial distribution of this species during 2021–2100. We evaluated two CO2 emission scenarios: RCP8.5 (high CO2 emissions, low mitigation efforts) and RCP4.5 (medium CO2 emissions and mitigation efforts). We found that the increase in temperature and decrease in prey density were the main drivers of faster growth rates and lower survival through increased starvation by the end of the century. Conversely, pCO2 had negligible impacts, which suggests that this species might be resilient to ocean acidification. The largest effects were observed under the high CO2 emission scenario, while the RCP4.5 projections displayed minimal impacts. We also identified an area with favourable conditions in the southeastern Bering Sea that will likely persist in future decades. This study provides relevant information on the future impacts of climate change on Pacific cod, and our results can be used to implement and inform climate-ready management for this important stock in Alaska.

An ancestral fold reveals the evolutionary link between RNA polymerase and ribosomal proteins

Numerous molecular machines are required to drive the central dogma of molecular biology. However, the means by which these numerous proteins emerged in the early evolutionary stage of life remains enigmatic. Many of them possess small β-barrel folds with different topologies, represented by double-psi β-barrels (DPBBs) conserved in DNA and RNA polymerases, and similar but topologically distinct six-stranded β-barrel RIFT or five-stranded β-barrel folds such as OB and SH3 in ribosomal proteins. Here, we discover that the previously reconstructed ancient DPBB sequence could also adopt a β-barrel fold named Double-Zeta β-barrel (DZBB), as a metamorphic protein. The DZBB fold is not found in any modern protein, although its structure shares similarities with RIFT and OB. Indeed, DZBB could be transformed into them through simple engineering experiments. Furthermore, the OB designs could be further converted into SH3 by circular-permutation as previously predicted. These results indicate that these β-barrels diversified quickly from a common ancestor at the beginning of the central dogma evolution.

Exposure Effects of Environmentally Relevant Concentrations of the Tricyclic Antidepressant Amitriptyline in Early Life Stage Zebrafish.

Antidepressants are one of the most globally prescribed classes of pharmaceuticals, and drug target conservation across phyla means that nontarget organisms may be at risk from the effects of exposure. Here, we address the knowledge gap for the effects of chronic exposure (28 days) to the tricyclic antidepressant amitriptyline (AMI) on fish, including for concentrations with environmental relevance, using zebrafish (Danio rerio) as our experimental model. AMI was found to bioconcentrate in zebrafish, was readily transformed to its major active metabolite nortriptyline, and induced a pharmacological effect (downregulation of the gene encoding the serotonin transporter; slc6a4a) at environmentally relevant concentrations (0.03 μg/L and above). Exposures to AMI at higher concentrations accelerated the hatch rate and reduced locomotor activity, the latter of which was abolished after a 14 day period of depuration. The lack of any response on the features of physiology and behavior we measured at concentrations found in the environment would indicate that AMI poses a relatively low level of risk to fish populations. The pseudopersistence and likely presence of multiple drugs acting via the same mechanism of action, however, together with a global trend for increased prescription rates, mean that this risk may be underestimated using current ecotoxicological assessment paradigms.

Environmental conditions differently shape leaf, seed and seedling trait composition between and within elevations of tropical montane forests

The composition of plant functional traits varies in response to environmental conditions due to processes of community assembly and species sorting. However, there is a lack of understanding of how plant trait composition responds to environmental conditions at different spatial scales and across the plant life cycle. We investigated the trait composition of leaves (specific leaf area), seeds (seed mass) and seedlings (initial seedling height) across elevations and within elevations in relation to soil and light conditions in a tropical montane forest in southern Ecuador. We surveyed traits and communities of adult trees, seeds and seedlings on nine plots at three elevations (1000–3000 m a.s.l.) and calculated community‐weighted mean trait values to analyse trait variation across and within elevations. In addition, we measured two environmental factors (soil C/N ratio and canopy openness) to quantify local‐scale variation in environmental conditions within elevations. We found that community‐weighted means of specific leaf area, seed mass and initial seedling height decreased consistently with increasing elevation. Within elevations, mean trait values of trees, seeds and seedlings responded differently to local‐scale environmental conditions. Specific leaf area decreased with increasing soil C/N ratio, and initial seedling height decreased with increasing canopy openness. Seed mass was associated neither with soil nor with light conditions. Our findings show that broad‐scale and local‐scale processes differently shape the composition of leaf, seed and seedling traits in tropical forests, indicating a scale‐dependence in trait–environment associations. Furthermore, plant traits corresponding to different life stages were related differently to environmental conditions within elevations. Community assembly processes may therefore lead to differences in species sorting at early and late plant life stages.

Not enough trees – Scaling up koala habitat restoration using seed enhancement technologies

AbstractLarge‐scale ecological restoration is a crucial tool for improving the quality and extent of habitat for wildlife. In Australia, 25,000 hectares of land is to be restored to support habitat connectivity for the Endangered koala (Phascolarctos cinereus). However, limited funding is a barrier to achieving restoration of this scale without the integration of new technologies and approaches. Seed enhancement technologies (SETs) are commonly used in agriculture to improve plant establishment and growth while reducing seed wastage; yet SETs are rarely used in restoration. Here, we tested the efficacy of SETs with five native tree species favored by koalas. Using a greenhouse trial, we measured emergence, time to emergence, growth rates, and survival up to 7 weeks post planting. At 33 weeks post‐planting, we measured total biomass, root: shoot ratios, and the specific root length. SETs resulted in comparable emergence and survival and promoted a longer time to emergence relative to bare seeds. Importantly, seedlings grown from SETs yielded higher average growth rates (0.3 mm/week higher), total biomass (5.93 mg higher) and root: shoot ratios (0.258 higher) relative to seedlings grown without SETs. These findings underscore the applicability of SETs to native species to support large‐scale koala habitat restoration by increasing the growth rate and size of seedlings at the early life stage.

Charting Alzheimer's Disease and Dementia: Epidemiological Insights, Risk Factors and Prevention Pathways.

Alzheimer's disease (AD), the most common cause of dementia, is a complex and multifactorial condition without cure at present. The latest treatments, based on anti-amyloid monoclonal antibodies, have only a modest effect in reducing the progression of cognitive decline in AD, whereas the possibility of preventing AD has become a crucial area of research. In fact, recent studies have observed a decrease in dementia incidence in developed regions such as the US and Europe. However, these trends have not been mirrored in non-Western countries (Japan or China), and the contributing factors of this reduction remain unclear. The Lancet Commission has delineated a constrained classification of 12 risk factors across different life stages. Nevertheless, the scientific literature has pointed to over 200 factors-including sociodemographic, medical, psychological, and sociocultural conditions-related to the development of dementia/AD. This narrative review aims to synthesize the risk/protective factors of dementia/AD. Essentially, we found that risk/protective factors vary between individuals and populations, complicating the creation of a unified prevention strategy. Moreover, dementia/AD explanatory mechanisms involve a diverse array of genetic and environmental factors that interact from the early stages of life. In the future, studies across different population-based cohorts are essential to validate risk/protective factors of dementia. This evidence would help develop public health policies to decrease the incidence of dementia.

The Influence of Feeding Practice on the Risk of Stunting in Toddler: A Scoping Review

Child stunting is a serious case that is difficult to overcome because it is caused by poor food quality and the amount of food that does not meet the body's needs during the first two years of life. The purpose of this study is to review the influence of feeding practices and feeding methods on the risk of stunting in children under five. PRISMA-ScR reporting guidelines are used to identify key concepts and knowledge gaps. This scoping review used a five-step framework approach. The databases used were PubMed, Wiley Online Library, ScienceDirect, and EBSCO. Manual searches used the Research Rabbit search engine. Based on the search results of 979 articles, ten articles were found that matched the inclusion criteria. Out of the seven themes found, four were in line with WHO's complementary feeding indicators, namely Minimum Meal Frequency (MMF), Minimum Dietary Diversity (MDD), Minimum Acceptable Diet (MAD), and Introduction of Solid, Semi-Solid or Soft Foods (ISSSF). While the other three themes are a time of first feeding, breastfeeding practices, and feeding methods. Overall, inadequate feeding practices result in child malnutrition, including stunting. Improper nutrition and care during the first 1000 days of birth is detrimental to a child's life, both in the short and long term as malnutrition that occurs at this early stage of life has serious and irreversible consequences. Large-scale studies are recommended to explore the role of IYCF in reducing stunting and qualitative studies to determine barriers and drivers to improve infant and young child feeding practices.

Association between composite dietary antioxidant and bone mineral density in children and adolescents aged 8–19 years: findings from NHANES

Dietary antioxidants may have beneficial effects on bone health, but it remains uncertain in children and adolescents. This study investigates the association of composite dietary antioxidant index (CDAI) with bone mineral density (BMD) in children and adolescents aged 8–19 years from the National Health and Nutrition Examination Survey (NHANES) 2007–2010. The study assessed the relationship between CDAI and BMD in 2994 individuals aged 8–19 years (average age 13.48 ± 3.32 years) from the NHANES 2007–2010. Multivariate linear regression analyses were utilized to detect the association between CDAI and total spine, femur neck, and total femur BMD, adjusting for confounders including age, race/ethnicity, sex, poverty income ratio (PIR), body mass index (BMI), serum phosphorus and calcium. Stratified analyses and interaction tests were performed to examine the stability of the results. The weighted characteristics showed that subjects in the fourth CDAI quartile were more likely to be older, men, and Non-Hispanic White. They have higher values of serum total calcium and phosphorus. After adjusting all confounders, CDAI was positively associated with the total spine (β = 0.0031 95% CI 0.0021–0.0040), total femur (β = 0.0039 95% CI 0.0028–0.0049), and femur neck BMD (β = 0.0031 95% CI 0.0021–0.0040) in children and adolescents. Furthermore, we found no interaction effects between different race/ethnicity, age, and sex groups. Our findings suggest that dietary intake of multiple antioxidants was positively associated with BMD in children and adolescents. These findings provide valuable evidence for improving bone health in the early stages of life. However, more prospective studies are required to validate our findings and their causal relationship.

Pachycereus pringlei seedling emergence and establishment under different lighting conditions

Cactus early life stages, especially in arid ecosystems, are typically the most vulnerable; seedlings face various abiotic and biotic filters to achieve survival and successful integration into their habitat. Thus, Pachycereus pringlei – endemic to Mexican Sonoran Desert – plays a crucial role in the arid areas of Baja California Sur, Mexico acting as a refuge and food source for wildlife. The present study evaluates P. pringlei emergence, survival, and seedling growth under different solar exposure (open and shaded areas) levels, both in greenhouse and natural conditions. The results indicated that natural conditions and moisture significantly influenced seedling emergence and survival. Lack of soil moisture led to compaction, which may have reduced porous spaces and restricted air and water circulation, thereby affecting root growth during the establishment phase. Conversely, the emerged seedling proportion under greenhouse shade was higher than in natural conditions. Additionally, these seedlings exhibited superior stem development, while those exposed to sunlight notably developed root systems. Low water potential was recorded, reaching down to -5.1 MPa for seedlings exposed to higher light levels. However, relative water content (RWC) values in tissues exceeded 70 %. No significant relationship was found between photosynthetic pigment concentration and different light conditions. Despite adapting cacti to xeric environments, the results suggest they may not be fully prepared to withstand prolonged drought episodes during the seedling stage. Nevertheless, some morphological traits, such as stem length, spines, and root area showed significant variations under different light conditions, facilitating photosynthesis light capture.

The effects of music on brain development

The influence of music on brain development is a complex and widely studied area in science. Studies show that being exposed to music, especially in early stages of life, can improve different cognitive abilities like language, reasoning, and spatial-temporal skills. Engaging with music also helps in regulating emotions and developing social skills. Furthermore, music education supports creativity and self-expression, which are crucial for overall brain development. With a deeper understanding of how music affects the brain at a neurological level, educators, therapists, and parents can leverage its advantages to enhance well-being and cognitive functions for people of all ages.

Effects of low temperature on growth and metabolism of larval green sturgeon (Acipenser medirostris) across early ontogeny.

Southern Distinct Population Segment (sDPS) green sturgeon spawn solely in one stretch of the Sacramento River in California. Management of this spawning habitat is complicated by cold water temperature requirements for the conservation of winter-run Chinook salmon. This study assessed whether low incubation and rearing temperatures resulted in carryover effects across embryo to early juvenile life stages on scaling relationships in growth and metabolism in northern DPS green sturgeon used as a proxy for sDPS green sturgeon. Fish were incubated and reared at 11°C and 15°C, with a subset experiencing a reciprocal temperature transfer post-hatch, to assess recovery from cold incubation or to simulate a cold-water dam release which would chillrearing larvae. Growth and metabolic rate of embryos and larvae were measured to 118days post hatch. Reciprocal temperature transfers revealed a greater effect of low temperature exposure during larval rearing rather than during egg incubation. While 11°C eggs hatched at a smaller length, log-transformed length-weight relationships showed that these differences in developmental trajectory dissipated as individuals achieved juvenile morphology. However, considerable size-at-age differences persisted between rearing temperatures, with 15°C fish requiring 60days post-hatch to achieve 1g in mass, whereas 11°C fish required 120days to achieve 1g, resulting in fish of the same age at the completion of the experiment with a ca. 37-fold difference in weight. Consequently, our study suggests that cold rearing temperatures have far more consequential downstream effects than cold embryo incubation temperatures. Growth delays from 11°C rearing temperatures would greatly increase the period of vulnerability to predation in larval green sturgeon. The scaling relationship between log-transformed whole-body metabolism and mass exhibited a steeper slope and thus an increased oxygen requirement with size in 11°C reared fish, potentially indicating an energetically unsustainable situation. Understanding how cold temperatures affect green sturgeon ontogeny is necessary to refine our larval recruitment estimations for this threatened species.