Find research datasets worth reusing

opencc-by-4.0Dec 2021View details →

The data for the article entitled "Nitrogen deposition drives response and recovery to precipitation change and its reversal in an arid ecosystem""

Title: Nitrogen deposition drives response and recovery to precipitation change and its reversal in an arid ecosystem Yu et al. Document 1: Data on plant community traits. Document 2: Data on soil features.

Anna's hummingbird (Calypte anna) physiological response to novel thermal and hypoxic conditions at high elevations

Many species have not tracked their thermal niches upslope as predicted by climate change, potentially because higher elevations are associated with abiotic challenges beyond temperature. To better predict if organisms can continue to move upslope with rising temperatures, we need to understand their physiological performance when subjected to novel high elevation conditions. Here, we captured Anna's hummingbirds – a species expanding their elevational distribution in concordance with rising temperatures – from across their current elevational distribution and tested their physiological response to novel abiotic conditions. First, at a central aviary within their current elevational range, we measured hovering metabolic rate to assess their response to oxygen conditions and torpor use to assess their response to thermal conditions. Second, we transported the hummingbirds to a location 1200 meters above their current elevational range limit to test an acute response to novel oxygen and thermal conditions. Hummingbirds exhibited lower hovering metabolic rates above their current elevational range limit, suggesting lower oxygen availability may reduce performance after an acute exposure. Alternatively, hummingbirds showed a facultative response to thermal conditions by using torpor more frequently and longer. Finally, post-experimental dissection found that hummingbirds originating from higher elevations within their range had larger hearts, a potential plastic response to hypoxic environments. Overall, our results suggest lower oxygen availability and low air pressure may be difficult challenges to overcome for hummingbirds shifting upslope due to rising temperatures, especially if there is little to no long-term acclimatization. Future studies should investigate how chronic exposure and acclimatization to novel conditions, as opposed to acute experiments, may result in alternative outcomes that help organisms better respond to abiotic challenges associated climate-induced range shifts.

opencc-by-4.0Dec 2021View details →

Impact of CD4 T cells on intratumoral CD8 T cell exhaustion and responsiveness to PD-1 blockade therapy in mouse brain tumors

scRNA-seq data (Cellranger filtered feature-barcode matrices) and scVDJ-seq data (Cellranger filtered_contig_annotations.csv files) for publication listed above.

Raw data for: Plastic responses of males and females interact to determine mating behaviour

Individuals can respond plastically to variation in their social environment. However, each sex may respond to different cues and contrasting aspects of competition. Theory suggests that the plastic phenotype expressed by one sex can influence evolutionary dynamics in the other, and that plasticity simultaneously expressed by both sexes can exert sex-specific effects on fitness. However, data are needed to test this theory base. Here, we examined whether the simultaneous expression of adaptive plasticity by both sexes of Drosophila melanogaster fruit flies in response to their respective social environments interacts to determine the value of key reproductive traits (mating latency, duration and fecundity). To vary social environments, males were kept alone, or with same sex rivals, and females were kept alone, in same-sex, or mixed-sex groups. Matings were then conducted between individuals from all of these 5 social treatments in all combinations, and the resulting reproductive traits measured in both 'choice' and 'no choice' assays. Mating latency was determined by an interaction between the plastic responses of both sexes to their social environments. Interestingly, the mating latency response occurred in opposing directions in the different assays. In females exposed to same-sex social treatments, mating latency was more rapid with rival treatment males in the choice assays, but slower with those same males in no choice assays. In contrast, mating duration was determined purely by responses of males to their social environments, and fecundity purely by responses of females. Collectively, the results show that plastic responses represent an important and novel facet of sexual interactions.

opencc-by-4.0May 2022View details →

A Semi-Empirical Framework for Ice Sheet Response Analysis under Oceanic Forcing in Antarctica and Greenland

Supplementary material for Luo, X. & Lin, T. (2022). “A Semi-Empirical Framework for Ice Sheet Response Analysis under Oceanic Forcing in Antarctica and Greenland.” Climate Dynamics, in press. <a href="https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fdoi.org%2F10.1007%2Fs00382-022-06317-x&data=05%7C01%7CXiao.Luo%40ttu.edu%7C2a6949c147dd4aa9880f08da345e55ae%7C178a51bf8b2049ffb65556245d5c173c%7C0%7C0%7C637879877007681605%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=2G3mD6n0ZOogcEFQcuCCElFmgKE0%2B%2F5KPTtzBeq8kM4%3D&reserved=0">https://doi.org/10.1007/s00382-022-06317-x</a> This repository contains data and scripts that are used to facilitate the analysis of Greenland and Antarctica ice sheet melting induced by ocean warming. The GCM directory contains ocean potential temperature time series for both Antarctica ice shelves near open sea retrieved from FGOALS-s2 under RCP 6.0 and Greenland store glacier retrieved from MIROC5 under RPC8.5 and HadGEM3-GC31-MM projections under update of RCP8.5 based on SSP5. The raw data are accessed from CMIP5 (https://esgf-node.llnl.gov/search/cmip5/) and CMIP6 (https://esgf-node.llnl.gov/search/cmip6/) projects respectively and the processed data deposited here are stored in Excel format. The WOD directory contains the NetCDF files of Present-Day ocean conditions including temperature, salinity, depth, and other variables retrieved from World Ocean Database (WOD).  The data are deposited as NetCDF format. The Analysis directory contains 3 subdirectories that illustrates the analysis workflow for both Greenland and Antarctica.          The Antarctica subdirectory contains the analysis codes to reproduce Antarctica ice shelf melting response and future projection. Antarctica_analysis.m is the main routine for computation and plotting, and the other files are input files including PISM/PICO simulations outputs and ocean temperature time series retrieved from CMIP5 project that can be found on the previous GCM directory.          The Greenland subdirectory contains the main routine store_analysis.m for Greenland Store glacier computation and plotting, the response time series (store.mat), perturbed response time series (store_pert.mat), ocean temperature projection (store_temp.mat) generated by MIROC5, and subglacial runoff time series (store_runoff.mat) estimated from annual basin surface runoff using MAR data forced by MIROC5 under RCP8.5.          The Historical subdirectory contains the data and scripts used for the historical analyses in the main text. AIS_melt_historical.m is the main script of the analysis, along with two other plotting functional scripts including plot_melt_rate.m and plot_ocean_temp.m. The input files include the PISM/PICO simulations outputs, which are the same files in Antarctica subdirectory, and other 2 input files that contain the temperature time series from 6 CMIP5 GCMs.

opencc-by-4.0May 2022View details →

Data for 'Using 40 years of spot measurements to assess stream temperature response and recovery for different harvesting systems in northern hardwood forests' by Jason Leach, Danielle Hudson and R. Dan Moore. Submitted to Hydrological Processes.

This dataset contains spot stream temperature measurements taken at 5 headwater streams draining forested hillslopes (C31, C32, C33, C34, C35) in the Turkey Lakes Watershed, approximately 65 km northwest of Sault Ste. Marie, Ontario, Canada.

opencc-by-4.0Jun 2022View details →

Other supporting data for our manuscript "Mapping the Single Cell Transcriptomic Response of Murine Diabetic Kidney Disease to Therapies"

Other supplementary data for our paper "Mapping the Single Cell Transcriptomic Response of Murine Diabetic Kidney Disease to Therapies"

Intraspecific trait changes in response to drought lead to trait convergence between- but not within species

Drought is expected to increase in future climate scenarios. Although responses to drought of individual functional traits are relatively well-known, simultaneous changes across multiple traits in response to water scarcity remain poorly understood despite its importance to understand alternative strategies to resist drought. We grew 52 herbaceous species in monocultures under drought and control treatments and characterized the functional space using seven measured above- and belowground traits: plant height, leaf area, specific leaf area, leaf dry matter content, specific root length, average root diameter, and root dry matter content. Then, we estimated how each species occupied this space and the amount of functional space occupied in both treatments using trait probability density functions. We also estimated intraspecific trait variability (ITV) for each species as the dissimilarity in trait values between the individuals of each treatment. We then mapped drought resistance and ITV in the functional space using generalized additive models. The response of species to drought strongly depended on their traits, with species that invested more in root tissues and conserved small size being both more resistant to drought and having higher ITV. We also observed a significant trend of trait displacement towards less conservative strategies. However, these changes depended strongly on the trait values of species in the control treatment, with species with different traits having opposing responses to drought. These contrasting responses resulted in lower trait variability in the species pool in drought compared to control conditions. Our results suggest strong trait filtering acting on conservative species as well as the existence of an optimal part in the functional space to which species converge under drought. Our results show that changes in species trait-space occupancy are key to understand plant strategies to withstand drought, highlighting the importance of individual variation in response to environmental changes, and suggest that community-wide functional diversity and biomass productivity could decrease in a drier future. Knowing these shifts will help to anticipate changes in ecosystem functioning facing climate change.

Data from: Kinematic trajectories in response to speed perturbations in walking suggest modular task-level control of leg angle and length

Abstract Navigating complex terrains requires dynamic interactions between the substrate, musculoskeletal and sensorimotor systems. Current perturbation studies have mostly used visible terrain height perturbations, which do not allow us to distinguish among the neuromechanical contributions of feedforward control, feedback-mediated and mechanical perturbation responses. Here, we use treadmill belt speed perturbations to induce a targeted perturbation to foot speed only, and without terrain-induced changes in joint posture and leg loading at stance onset. Based on previous studies suggesting a proximo-distal gradient in neuromechanical control, we hypothesized that distal joints would exhibit larger changes in joint kinematics, compared to proximal joints. Additionally, we expected birds to use feedforward strategies to increase the intrinsic stability of gait. To test these hypotheses, seven adult guinea fowl were video recorded while walking on a motorized treadmill, during both steady and perturbed trials. Perturbations consisted of repeated exposures to a deceleration and acceleration of the treadmill belt speed. Surprisingly, we found that joint angular trajectories and center of mass fluctuations remain very similar, despite substantial perturbation of foot velocity by the treadmill belt. Hip joint angular trajectories exhibit the largest changes, with the birds adopting a slightly more flexed position across all perturbed strides. Additionally, we observed increased stride duration across all strides, consistent with feedforward changes in the control strategy. The speed perturbations mainly influenced the timing of stance and swing, with the largest kinematic changes in the strides directly following a deceleration. Our findings do not support the general hypothesis of a proximo-distal gradient in joint control, as distal joint kinematics remain largely unchanged. Instead, we find that leg angular trajectory and the timing of stance and swing are most sensitive to this specific perturbation, and leg length actuation remains largely unchanged. Our results are consistent with modular task-level control of leg length and leg angle actuation, with different neuromechanical control and perturbation sensitivity in each actuation mode. Distal joints appear to be sensitive to changes in vertical loading but not foot fore-aft velocity. Future directions should include in vivo studies of muscle activation and force-length dynamics to provide more direct evidence of the sensorimotor control strategies for stability in response to belt speed perturbations.

A gas-only bioreactor system maintains stable culture environments and reveals that moderate pH deviations trigger transcriptome-wide responses in human cells cultured in physioxia and physiological buffers

Although pH instability is emerging as a potential driver of changes in cell physiology, pH is still poorly controlled during cell culture and in vitro experiments. Standard procedures include the use of chemicals usually not present in the primary physiological buffering system (CO2/HCO3-), such as acids and bases, to manipulate pH levels. This, however, leads to artifacts that potentially affect scientists' findings. Here, we propose a novel method for controlling pH levels by relying only on the physiological buffering system. pH was manipulated in a repurposed commercial bioreactor set-up, using a two-sided control loop of CO2 and N2 gas in NaHCO3--buffered medium. This method produces optimal and stable dO2 profiles and tightly maintains pH levels. With this procedure, we analyzed the effects of different pH levels (6.8, 7.0, 7.2, and 7.4) on the performance and transcriptome of the human GM12878 cell line over a 72-hours experiment. Our results showed that inflammation and negative cellular proliferation are among the signatures activated at low pH. This further highlights the importance of a thorough pH control during cell culture.

Riding an escalator: upward range shift and patterns of genetic response to climate change in Acer caudatifolium

Aim Rapid global warming is threatening global biodiversity, and it will likely lead to varying degrees of local adaptation, particularly among plant species. Besides, rising temperatures frequently result in upslope distribution shifts towards climatic optima (i.e., the escalator effect) within a limited dispersal space, such as in insular environments. Here, we integrated ecological and genetic approaches to investigate how climate change will impact the genetic compositions and spatial distributions of Taiwan endemic maple Acer caudatifolium. Location Taiwan Methods We estimate the distribution range shifts of A. caudatifolium under climate change through species distribution modeling (SDM). We also use 368 genotyped samples to infer dispersal and genetic hotspots and quantify the contributions of geography/environments to genetic variations. We further assess the potential risk to A. caudatifolium under different climate warming scenarios. Results We detected three genetic diversity hotspots near mountainous glacial refugia and two dispersal hotspots in northern Taiwan and the central-to-southern Central Mountain Range. Overall range reductions and an altitudinal upslope-shift were observed in SDM. Using both linear and nonlinear regression approaches, we found that genetic variation was significantly associated with geographic distance and elevation-related climatic variables. The potential risk analysis revealed that the northernmost summit-dwelling populations were the most vulnerable. Furthermore, the major risk factor differed among populations: for central populations, temperature and precipitation jointly determined the potential risk, whereas precipitation was the only risk factor for northern and southern populations. Main conclusions This case study demonstrates how various climate factors, mountain height, and the availability of corridors jointly determine the demographic fates and sustainability of island maples in the face of climate change. This study also provided estimates of the implications of global warming, which can be conducive to developing appropriate conservation strategies.

Plasticity across levels: relating epigenomic, transcriptomic, and phenotypic responses to osmotic stress in a halotolerant microalga

Phenotypic plasticity, the ability of a given genotype to produce alternative phenotypes in response to its environment of development, is an important mechanism for coping with variable environments. While the mechanisms underlying phenotypic plasticity are diverse, their relative contributions need to be investigated quantitatively to better understand the evolvability of plasticity across biological levels. This requires relating plastic responses of the epigenome, transcriptome, and organismal phenotype, and investigating how they vary with the genotype. Here we carried out this approach for responses to osmotic stress in Dunaliella salina, a green microalga that is a model organism for salinity tolerance. We compared two strains that show markedly different demographic responses to osmotic stress, and showed that these phenotypic responses involve strain- and environment-specific variation in gene expression levels, but a relative low - albeit significant - effect of strain × environment interaction. We also found an important genotype effect on the genome-wide methylation pattern, but little contribution from environmental conditions to the latter. However, we did detect a significant marginal effect of epigenetic variation on gene expression, beyond the influence of genetic differences on epigenetic state, and we showed that hypomethylated regions are correlated with higher gene expression. Our results indicate that epigenetic mechanisms are either not involved in the rapid plastic response to environmental change in this species, or involve only few changes in trans that are sufficient to trigger concerted changes in the expression of many genes, and phenotypic responses by multiple traits.

Quantifying within-species trait variation in space and time reveals limits to trait-mediated drought response

Climate change is stressing many forests around the globe, yet some tree species may be able to persist through acclimation and adaptation to new environmental conditions. The ability of a tree to acclimate during its lifetime through changes in physiology and functional traits, defined here as its acclimation potential, is not well known. We investigated the acclimation potential of trembling aspen (Populus tremuloides) and ponderosa pine (Pinus ponderosa) trees by examining within-species variation in drought response functional traits across both space and time, and how trait variation influences drought-induced tree mortality. We measured xylem tension, morphological traits, and physiological traits on mature trees in southwestern Colorado, USA across a climate gradient that spanned the distribution limits of each species and three years with large differences in climate. Trembling aspen functional traits showed high within-species variation, and osmotic adjustment and carbon isotope discrimination were key determinants for increased drought tolerance in dry sites and in dry years. However, trembling aspen trees at low elevation were pushed past their drought tolerance limit during the severe 2018 drought year, as elevated mortality occurred. Higher specific leaf area during drought was correlated with higher percentages of canopy dieback the following year. Ponderosa pine functional traits showed less within-species variation, though osmotic adjustment was also a key mechanism for increased drought tolerance. Remarkably, almost all traits varied more year-to-year than across elevation in both species. Our results shed light on the scope and limits of intraspecific trait variation for mediating drought responses in key southwestern US tree species and will help improve our ability to model and predict forest responses to climate change.

Off-target integron activity leads to rapid plasmid compensatory evolution in response to antibiotic selection pressure

Integrons are mobile genetic elements that have played an important role in the dissemination of antibiotic resistance. As shown previously (Souque et al, 2021), the integron can generate under stress combinatorial variation in resistance cassette expression by cassette re-shuffling, accelerating the evolution of resistance. However, the flexibility of the integron integrase site recognition motif hints at potential off-target effects of the integrase on the rest of the genome that may have important evolutionary consequences. Here we test this hypothesis by selecting for increased piperacillin resistance populations of P.aeruginosa with a mobile integron containing a hard-to-mobilise beta-lactamase cassette to minimize the potential for adaptive cassette re-shuffling. We found that integron activity can both decrease overall survival rate but also improve the fitness of the surviving populations. Off-target inversions mediated by the integron accelerated plasmid adaptation by disrupting costly conjugative genes otherwise mutated in control populations lacking a functional integrase. Plasmids containing integron-mediated inversions were associated with lower plasmid costs and higher stability than plasmids carrying mutations, albeit at a cost of reduced conjugative ability. These findings highlight the potential for integrons to create structural variation that can drive bacterial evolution, and they provide an interesting example showing how antibiotic pressure can drive the loss of conjugative genes.

Can antioxidant responses be induced by habitat fragmentation process?

Animal populations are increasingly forced to live in small residual natural or semi-natural areas due to habitat loss and fragmentation. Here, the viability of populations is often compromised by intrinsic threat factors typical of small and isolated populations, such as inbreeding depression, genetic drift, and environmental and demographic stochasticity. Under these circumstances, organisms may have low fitness due to inadequate physiological responses needed to face environmental challenges. However, few studies have investigated the relationship between habitat fragmentation and stress defences. In this study, we aimed to test whether an increase in the level of individual inbreeding produced an increase in the antioxidant system response. To this purpose, we genotyped 151 individuals of Fire Salamander Salamandra salamandra (Amphibia: Urodela) within 5 sampling populations, located in forest landscapes with different degree of fragmentation in northern Italy. For 113 individuals we also measured the glutathione-S-transferase (GST) and catalase (CAT) enzyme activity. Results showed a significant increase in individual GST activity for increasing levels of inbreeding, whereas no relationship was found for CAT. We also measured acetylcholinesterase to test the possible confounding effects of pesticides that might have occurred in fragmented landscapes with forests interspersed with agricultural areas. However, no difference in this enzyme activity was found among sampling populations. We argue that high levels of GST activity may be symptomatic of oxidative stress derived from inbreeding. An increased frequency of homozygous deleterious alleles due to inbreeding may cause homeostatic alterations and trigger the expression of GST for protection against hydrogen peroxide reactive oxygen species. We suggest using GST as a biomarker for environmental stressors with great caution and not to underestimate that the sources of stress deriving from habitat fragmentation could lead to an unbalance in the oxidative status, possibly increasing population susceptibility to infectious diseases and, potentially, spillover events and zoonoses.

Beyond sex and aggression: Testosterone rapidly matches behavioral responses to social context and tries to predict the future

Although androgens are widely studied in the context of aggression, androgenic influences on prosocial behaviors have been less explored. We examined testosterone's (T) influence on prosocial and aggressive responses in a positively-valenced social context (interacting with a pairbond partner) and a negatively-valenced context (interacting with an intruder) in socially monogamous Mongolian gerbils. T increased and decreased prosocial responses in the same individuals towards a pairbond partner and an intruder, respectively, both within 30 minutes, but did not affect aggression. T also had persistent effects on prosocial behavior; males in which T initially increased prosocial responses towards a partner continued to exhibit elevated prosocial responses towards an intruder male days later until a second T injection rapidly eliminated those responses. Thus, T surges can rapidly match behavior to current social context, as well as prime animals for positive social interactions in the future. Neuroanatomically, T rapidly increased hypothalamic oxytocin, but not vasopressin, cellular responses during interactions with a partner. Together, our results indicate that T can facilitate and inhibit prosocial behaviors depending on social context, that it can influence prosocial responses across rapid and prolonged time scales, and that it affects oxytocin signaling mechanisms that could mediate its context-dependent behavioral influences.

The force response of muscles to activation and length perturbations depends on length history

Recent studies have demonstrated that muscle force is not determined solely by activation under dynamic conditions, and that length history has an important role in determining dynamic muscle force. Yet, the mechanisms for how muscle force is produced under dynamic conditions remain unclear. To explore how muscle force production is determined under dynamic conditions, we investigated the effects of muscle stiffness, activation, and length perturbations on muscle force. First, submaximal isometric contraction was established for whole soleus muscles. Next, the muscles were actively shortened at three velocities. During active shortening, we measured muscle stiffness at L0 and the force response to time-varying activation and length perturbations. We found that muscle stiffness increased with activation but decreased as shortening velocity increased. The slope of the relationship between maximum force and activation amplitude differed significantly among shortening velocities. Also, the intercept and slope of the relationship between length perturbation amplitude and maximum force decreased with shortening velocities. As shortening velocities were related with muscle stiffness, the results suggest that length history determines muscle stiffness and the history-dependent muscle stiffness influences the contribution of activation to muscle force and the contribution of length perturbations to muscle force. A three-parameter viscoelastic model that included a linear spring and linear damper in parallel with tunable history-dependent spring stiffness proportional to measured muscle stiffness predicted history-dependent muscle force with high accuracy. The results and simulations support the hypothesis that muscle force under dynamic conditions can be accurately predicted as the force response of a history-dependent viscoelastic material to length perturbations.

CeA Psilocin fiber photometry study: Data and custom code from experiments looking at changes in calcium dynamics in response to an air puff events

Psilocybin, and its active metabolite psilocin, have been shown to elicit rapid and long-lasting symptom improvements in a variety of affective psychiatric illnesses. However, the specific mechanisms behind these therapeutic effects remain relatively unknown. The central amygdala (CeA) is a primary output region within the extended amygdala that is heavily dysregulated in affective psychiatric disorders. Here, we utilized fiber photometry to measure changes in CeA reactivity to an aversive air puff stimulus after psilocin administration, both acutely and at varying prolonged time points. We found that administration of psilocin increased reactivity acutely in females, but not males. Additionally, we show that one dose of psilocin produced decreases in reactivity in males, but not females, 28-days post administration, with decreases seen as early as 2-days post administration. We further report stimulus-specific changes in CeA reactivity after psilocin with differential responsivity to an aversive air puff stimulus and an auditory stimulus. We also measured changes in behavioral response to the air puff stimulus and report sex differences in exploratory behavior but not threat responding or general locomotion. This study provides evidence that a single dose of psilocin can elicit sex-specific, dynamic, and enduring changes in CeA reactivity to an aversive stimulus. These data are an important step towards dissecting circuit-based mechanisms underlying the effects of psychedelics.

TRPM8 thermosensation in ectotherms mediates both skin colour and locomotor performance responses to cold temperature

Thermoregulation is a homeostatic process to maintain an organism's internal temperature within a physiological range compatible with life. In ectotherms, body temperature fluctuates with that of the environment, with both physiological and behavioral responses employed to modify body temperature. Changing skin colour/reflectance and locomotor activity are both well-recognized temperature regulatory mechanisms, but little is known of the participating thermosensor/s. We find that Xenopus laevis tadpoles put in the cold exhibit a temperature-dependent and rapid melanosome aggregation in melanophores, which lightens the skin. To identify the cold-sensor, we focused on transient receptor potential (trp) channel genes from group 1 (TRPA, TRPM, TRPV and TRPC families). Of particular interest were TRPM family members, known as cold sensors. mRNAs for several TRPMs are present in Xenopus tails, and TRPM8 protein is present in skin melanophores. Temperature-induced melanosome aggregation is mimicked by the Trpm8 agonist menthol (WS12) and blocked by the Trpm8 antagonist PF05105679. The degree of skin lightening induced by cooling or the WS12 TRPM8 agonist correlates with the extent of alterations in locomotor performance. We propose that TRPM8 serves as a cool thermosensor in ectotherms that helps coordinate skin lightening and behavioural locomotor performance as adaptive thermoregulatory responses to cold.

Data from: Girth increment changes in response to soil water availability in lowland dipterocarp forest in Borneo: an individualistic time-series analysis

Time-series data offer a way of investigating the causes driving ecological processes as phenomena. To test for possible differences in water relations between species of different forest structural guilds at Danum (Sabah, NE Borneo), daily stem girth increments (gthi), of 18 trees across six species were regressed individually on soil moisture potential (SMP) and temperature (TEMP), accounting for temporal autocorrelation (in GLS-arima models), and compared between a wet and a dry period. The best-fitting significant variables were SMP the day before and TEMP the same day. The first resulted in a mix of positive and negative coefficients, the second largely positive ones. An adjustment for dry-period showers was applied. Interactions were stronger in dry than wet period. Negative relationships for overstorey trees can be interpreted in a reversed causal sense: fast transporting stems depleted soil water and lowered SMP. Positive relationships for understorey trees meant they took up most water at high SMP. The unexpected negative relationships for these small trees may have been due to their roots accessing deeper water supplies (if SMP was inversely related to that of the surface layer), and this was influenced by competition with larger neighbour trees. A tree-soil flux dynamics manifold may have been operating. Patterns of mean diurnal girth variation were more consistent among species, and time-series coefficients were negatively related to their maxima. Expected differences in response to SMP in the wet and dry periods did not clearly support a previous hypothesis differentiating drought and non-drought tolerant understorey guilds. Trees within species showed highly individual responses when tree size was standardized. Data on individual root systems and SMP at several depths are needed to get closer to the mechanisms that underlie the tree-soil water phenomena in these tropical forests. Neighborhood stochasticity importantly creates varying local environments experienced by individual trees.