Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

The latitudinal temperature gradient and its climate dependence as inferred from foraminiferal δ¹⁸O over the past 95 million years.

ABSTRACT: SignificanceThe temperature difference between low and high latitudes is one measure of the efficiency of the global climate system in redistributing heat and is used to test the ability of models to represent the climate system through time. Here, we show that the latitudinal temperature gradient has exhibited a consistent inverse relationship with global mean sea-surface temperature for at least the past 95 million years. Our results help reduce conflicts between climate models and empirical estimates of temperature and argue for a fundamental consistency in the dynamics of heat transport and radiative transfer across vastly different background states.

SUBMITTER: Gaskell DE

PROVIDER: S-EPMC8931236 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

The latitudinal temperature gradient and its climate dependence as inferred from foraminiferal δ18O over the past 95 million years.

Gaskell Daniel E DE Huber Matthew M O'Brien Charlotte L CL Inglis Gordon N GN Acosta R Paul RP Poulsen Christopher J CJ Hull Pincelli M PM

Proceedings of the National Academy of Sciences of the United States of America 20220307 11

SignificanceThe temperature difference between low and high latitudes is one measure of the efficiency of the global climate system in redistributing heat and is used to test the ability of models to represent the climate system through time. Here, we show that the latitudinal temperature gradient has exhibited a consistent inverse relationship with global mean sea-surface temperature for at least the past 95 million years. Our results help reduce conflicts between climate models and empirical e ...[more]

PMID: 35254906

Similar Datasets

A 450 million years long latitudinal gradient in age-dependent extinction.

Project description:Leigh Van Valen famously stated that under constant conditions extinction probability is independent of species age. To test this 'law of constant extinction', we developed a new method using deep learning to infer age-dependent extinction and analysed 450 myr of marine life across 21 invertebrate clades. We show that extinction rate significantly decreases with age in > 90% of the cases, indicating that most species died out soon after their appearance while those which survived experienced ever decreasing extinction risk. This age-dependent extinction pattern is stronger towards the Equator and holds true when the potential effects of mass extinctions and taxonomic inflation are accounted for. These results suggest that the effect of biological interactions on age-dependent extinction rate is more intense towards the tropics. We propose that the latitudinal diversity gradient and selection at the species level account for this exceptional, yet little recognised, macroevolutionary and macroecological pattern.

| S-EPMC7027860 | biostudies-literature

The benthic foraminiferal δ34S records flux and timing of paleo methane emissions.

Project description:In modern environments, pore water geochemistry and modelling simulations allow the study of methane (CH4) sources and sinks at any geographic location. However, reconstructing CH4 dynamics in geological records is challenging. Here, we show that the benthic foraminiferal δ34S can be used to reconstruct the flux (i.e., diffusive vs. advective) and timing of CH4 emissions in fossil records. We measured the δ34S of Cassidulina neoteretis specimens from selected samples collected at Vestnesa Ridge, a methane cold seep site in the Arctic Ocean. Our results show lower benthic foraminiferal δ34S values (∼20‰) in the sample characterized by seawater conditions, whereas higher values (∼25-27‰) were measured in deeper samples as a consequence of the presence of past sulphate-methane transition zones. The correlation between δ34S and the bulk benthic foraminiferal δ13C supports this interpretation, whereas the foraminiferal δ18O-δ34S correlation indicates CH4 advection at the studied site during the Early Holocene and the Younger-Dryas - post-Bølling. This study highlights the potential of the benthic foraminiferal δ34S as a novel tool to reconstruct the flux of CH4 emissions in geological records and to indirectly date fossil seeps.

| S-EPMC6987089 | biostudies-literature

Sex-biased transcriptome divergence along a latitudinal gradient

Project description:Although not all sex-dependent gene expression is adaptive, it is likely an important genomic mechanism that allows each sex to independently adapt to environmental changes. Among Drosophila species, sex-biased genes display remarkably consistent evolutionary patterns; male-biased genes evolve faster than unbiased genes in both coding sequence and expression level, suggesting sex-differences in selection through time. However, comparatively little is known of the evolutionary process shaping sex-biased expression within species. Latitudinal clines offer an opportunity to examine how changes in key ecological parameters also influence sex-specific selection and the evolution of sex-biased gene expression. We assayed male and female gene expression in Drosophila serrata along a latitudinal gradient in eastern Australia spanning most of its endemic distribution. Analysis of 11,631 genes across eight populations revealed strong sex differences in the frequency, mode, and strength of divergence. Divergence was far stronger in males than females and while latitudinal clines were evident in both sexes, male divergence was often population-specific, suggesting responses to localized selection pressures that do not covary predictably with latitude. While divergence was enriched for male-biased genes, there was no overrepresentation of X-linked genes in males. By contrast, X-linked divergence was elevated in females, especially for female biased genes. Many genes that diverged in D. serrata have homologs also showing latitudinal divergence in D. simulans and D. melanogaster on other continents, likely indicating parallel adaptation in these distantly related species. Our results suggest that sex differences in selection play an important role in shaping the evolution of gene expression over macro- and micro-ecological spatial scales.

2017-01-04 | GSE90733 | GEO

Response of Arctic benthic foraminiferal traits to past environmental changes.

Project description:The Arctic is subjected to all-encompassing disruptions in marine ecosystems caused by anthropogenic warming. To provide reliable estimates of how future changes will affect the ecosystems, knowledge of Arctic marine ecosystem responses to past environmental variability beyond the instrumental era is essential. Here, we present a novel approach on how to evaluate the state of benthic marine biotic conditions during the deglacial and Holocene period on the Northeast Greenland shelf. Benthic foraminiferal species were assigned traits (e.g., oxygen tolerance, food preferences) aiming to identify past faunal changes as a response to external forcing mechanisms. This approach was applied on sediment cores from offshore Northeast Greenland. We performed numerical rate-of-change detection to determine significant changes in the benthic foraminiferal traits. That way, the significant abrupt trait changes can be assessed across sites, providing a better understanding of the impact of climate drivers on the traits. Our results demonstrate that during the last ~ 14,000 years, bottom water oxygen is the main factor affecting the variability in the benthic foraminiferal faunas in this area. Our results show that significant changes in the traits correspond to drastic climate perturbations. Specifically, the deglacial-Holocene transition and mid-Holocene warm period exhibited significant change, with several trait turnovers.

| S-EPMC10719382 | biostudies-literature

Molecular evolution and the latitudinal biodiversity gradient.

Project description:Species density is higher in the tropics (low latitude) than in temperate regions (high latitude) resulting in a latitudinal biodiversity gradient (LBG). The LBG must be generated by differential rates of speciation and/or extinction and/or immigration among regions, but the role of each of these processes is still unclear. Recent studies examining differences in rates of molecular evolution have inferred a direct link between rate of molecular evolution and rate of speciation, and postulated these as important drivers of the LBG. Here we review the molecular genetic evidence and examine the factors that might be responsible for differences in rates of molecular evolution. Critical to this is the directionality of the relationship between speciation rates and rates of molecular evolution.

| S-EPMC3656639 | biostudies-other

A latitudinal phylogeographic diversity gradient in birds.

Project description:High tropical species diversity is often attributed to evolutionary dynamics over long timescales. It is possible, however, that latitudinal variation in diversification begins when divergence occurs within species. Phylogeographic data capture this initial stage of diversification in which populations become geographically isolated and begin to differentiate genetically. There is limited understanding of the broader implications of intraspecific diversification because comparative analyses have focused on species inhabiting and evolving in restricted regions and environments. Here, we scale comparative phylogeography up to the hemisphere level and examine whether the processes driving latitudinal differences in species diversity are also evident within species. We collected genetic data for 210 New World bird species distributed across a broad latitudinal gradient and estimated a suite of metrics characterizing phylogeographic history. We found that lower latitude species had, on average, greater phylogeographic diversity than higher latitude species and that intraspecific diversity showed evidence of greater persistence in the tropics. Factors associated with species ecologies, life histories, and habitats explained little of the variation in phylogeographic structure across the latitudinal gradient. Our results suggest that the latitudinal gradient in species richness originates, at least partly, from population-level processes within species and are consistent with hypotheses implicating age and environmental stability in the formation of diversity gradients. Comparative phylogeographic analyses scaled up to large geographic regions and hundreds of species can show connections between population-level processes and broad-scale species-richness patterns.

| S-EPMC5390966 | biostudies-literature

Correction: A latitudinal phylogeographic diversity gradient in birds.

Project description:[This corrects the article DOI: 10.1371/journal.pbio.2001073.].

| S-EPMC5510780 | biostudies-other

A foraminiferal δ(18)O record covering the last 2,200 years.

Project description:Thanks to the precise core dating and the high sedimentation rate of the drilling site (Gallipoli Terrace, Ionian Sea) we were able to measure a foraminiferal δ(18)O series covering the last 2,200 years with a time resolution shorter than 4 years. In order to support the quality of this data-set we link the δ(18)O values measured in the foraminifera shells to temperature and salinity measurements available for the last thirty years covered by the core. Moreover, we describe in detail the dating procedures based on the presence of volcanic markers along the core and on the measurement of (210)Pb and (137)Cs activity in the most recent sediment layers. The high time resolution allows for detecting a δ(18)O decennial-scale oscillation, together with centennial and multicentennial components. Due to the dependence of foraminiferal δ(18)O on environmental conditions, these oscillations can provide information about temperature and salinity variations in past millennia. The strategic location of the drilling area makes this record a unique tool for climate and oceanographic studies of the Central Mediterranean.

| S-EPMC4915278 | biostudies-literature

Assessment of dependence potential and abuse liability of Δ8-tetrahydrocannabinol in mice.

Project description:Delta-8-tetrahydrocannabinol (Δ8-THC) is a psychotropic cannabinoid produced in low quantities in the cannabis plant. Refinements in production techniques, paired with the availability of inexpensive cannabidiol substrate, have resulted in Δ8-THC being widely marketed as a quasi-legal, purportedly milder alternative to Δ9-THC. Yet, little research has probed the behavioral and physiological effects of repeated Δ8-THC use. The present study aimed to evaluate the effects of acute and repeated exposure to Δ8-THC. We hypothesized that Δ8-THC produces effects similar to Δ9-THC, including signs of drug tolerance and dependence. Adult male and female C57BL/6J mice were treated acutely with Δ8-THC (6.25-100 mg/kg, i.p.) or vehicle and tested in the tetrad battery to quantify cannabimimetic effects (i.e., catalepsy, antinociception, hypothermia, immobility) as compared with a non-selective synthetic cannabinoid (WIN 55,212-2) and Δ9-THC. As previously reported, Δ8-THC (≥12.5 mg/kg) induced cannabimimetic effects. Pretreatment with the CB1 receptor-selective antagonist rimonabant (3 mg/kg, i.p.) blocked each of these effects. In addition, repeated administration of Δ8-THC (50 mg/kg, s.c.) produced tolerance, as well as cross-tolerance to WIN 55,212-2 (10 mg/kg, s.c.) in tetrad, consistent with downregulated CB1 receptor function. Behavioral signs of physical dependence in the somatic signs, tail suspension, and marble burying assays were also observed following rimonabant-precipitated withdrawal from Δ8-THC (≥10 mg/kg BID for 6 days). Lastly, Δ8-THC produced Δ9-THC-like discriminative stimulus effects in both male and female mice. Together, these findings demonstrate that Δ8-THC produces qualitatively similar effects to Δ9-THC, including risk of drug dependence and abuse liability.

| S-EPMC10288383 | biostudies-literature

Functional trait space and the latitudinal diversity gradient.

Project description:The processes causing the latitudinal gradient in species richness remain elusive. Ecological theories for the origin of biodiversity gradients, such as competitive exclusion, neutral dynamics, and environmental filtering, make predictions for how functional diversity should vary at the alpha (within local assemblages), beta (among assemblages), and gamma (regional pool) scales. We test these predictions by quantifying hypervolumes constructed from functional traits representing major axes of plant strategy variation (specific leaf area, plant height, and seed mass) in tree assemblages spanning the temperate and tropical New World. Alpha-scale trait volume decreases with absolute latitude and is often lower than sampling expectation, consistent with environmental filtering theory. Beta-scale overlap decays with geographic distance fastest in the temperate zone, again consistent with environmental filtering theory. In contrast, gamma-scale trait space shows a hump-shaped relationship with absolute latitude, consistent with no theory. Furthermore, the overall temperate trait hypervolume was larger than the overall tropical hypervolume, indicating that the temperate zone permits a wider range of trait combinations or that niche packing is stronger in the tropical zone. Although there are limitations in the data, our analyses suggest that multiple processes have shaped trait diversity in trees, reflecting no consistent support for any one theory.

| S-EPMC4183280 | biostudies-literature