Abstract:
:Climate models with increased levels of carbon dioxide predict that global warming causes heating in the tropics, but investigations of ancient climates based on palaeodata have generally indicated cool tropical temperatures during supposed greenhouse episodes. For example, in the Late Cretaceous and Eocene epochs there is abundant geological evidence for warm, mostly ice-free poles, but tropical sea surface temperatures are generally estimated to be only 15-23 degrees C, based on oxygen isotope palaeothermometry of surface-dwelling planktonic foraminifer shells. Here we question the validity of most such data on the grounds of poor preservation and diagenetic alteration. We present new data from exceptionally well preserved foraminifer shells extracted from impermeable clay-rich sediments, which indicate that for the intervals studied, tropical sea surface temperatures were at least 28-32 degrees C. These warm temperatures are more in line with our understanding of the geographical distributions of temperature-sensitive fossil organisms and the results of climate models with increased CO2 levels.
journal_name
Naturejournal_title
Natureauthors
Pearson PN,Ditchfield PW,Singano J,Harcourt-Brown KG,Nicholas CJ,Olsson RK,Shackleton NJ,Hall MAdoi
10.1038/35097000keywords:
subject
Has Abstractpub_date
2001-10-04 00:00:00pages
481-7issue
6855eissn
0028-0836issn
1476-4687pii
35097000journal_volume
413pub_type
杂志文章相关文献
NATURE文献大全abstract::It is thought that neutron stars in low-mass binary systems can accrete matter and angular momentum from the companion star and be spun-up to millisecond rotational periods. During the accretion stage, the system is called a low-mass X-ray binary, and bright X-ray emission is observed. When the rate of mass transfer d...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature12470
更新日期:2013-09-26 00:00:00
abstract::In the ocean, the chemical forms of nitrogen that are readily available for biological use (known collectively as 'fixed' nitrogen) fuel the global phytoplankton productivity that exports carbon to the deep ocean. Accordingly, variation in the oceanic fixed nitrogen reservoir has been proposed as a cause of glacial-in...
journal_title:Nature
pub_type: 历史文章,杂志文章
doi:10.1038/nature12397
更新日期:2013-09-12 00:00:00
abstract::Genomic imprinting is an allele-specific gene expression system that is important for mammalian development and function. The molecular basis of genomic imprinting is allele-specific DNA methylation. Although it is well known that the de novo DNA methyltransferases Dnmt3a and Dnmt3b are responsible for the establishme...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature12805
更新日期:2013-12-19 00:00:00
abstract::A variety of observations indicate that mid-ocean ridges produce less crust at spreading rates below 20 mm yr(-1) (refs 1-3), reflecting changes in fundamental ridge processes with decreasing spreading rate. The nature of these changes, however, remains uncertain, with end-member explanations being decreasing shallow ...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature03140
更新日期:2004-12-09 00:00:00
abstract:: ...
journal_title:Nature
pub_type: 新闻
doi:10.1038/d41586-018-07667-5
更新日期:2018-12-01 00:00:00
abstract::Plasmacytoid dendritic cells (pDCs) sense viral and microbial DNA through endosomal Toll-like receptors to produce type 1 interferons. pDCs do not normally respond to self-DNA, but this restriction seems to break down in human autoimmune disease by an as yet poorly understood mechanism. Here we identify the antimicrob...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature06116
更新日期:2007-10-04 00:00:00
abstract::We are facing a global metabolic health crisis provoked by an obesity epidemic. Here we report the human gut microbial composition in a population sample of 123 non-obese and 169 obese Danish individuals. We find two groups of individuals that differ by the number of gut microbial genes and thus gut bacterial richness...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature12506
更新日期:2013-08-29 00:00:00
abstract::One hundred years ago Albert Einstein introduced the concept of the photon. Although in the early years after 1905 the evidence for the quantum nature of light was not compelling, modern experiments--especially those using photon pairs--have beautifully confirmed its corpuscular character. Research on the quantum prop...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature03280
更新日期:2005-01-20 00:00:00
abstract::This corrects the article DOI: 10.1038/nature24295. ...
journal_title:Nature
pub_type: 杂志文章,已发布勘误
doi:10.1038/nature25017
更新日期:2018-01-25 00:00:00
abstract::Calcitonin gene-related peptide (CGRP) is a widely expressed neuropeptide that has a major role in sensory neurotransmission. The CGRP receptor is a heterodimer of the calcitonin receptor-like receptor (CLR) class B G-protein-coupled receptor and a type 1 transmembrane domain protein, receptor activity-modifying prote...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/s41586-018-0535-y
更新日期:2018-09-01 00:00:00
abstract::The 5'-->3' exoribonucleases (XRNs) comprise a large family of conserved enzymes in eukaryotes with crucial functions in RNA metabolism and RNA interference. XRN2, or Rat1 in yeast, functions primarily in the nucleus and also has an important role in transcription termination by RNA polymerase II (refs 7-14). Rat1 exo...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature07731
更新日期:2009-04-09 00:00:00
abstract::Over the past eight hundred thousand years, glacial-interglacial cycles oscillated with a period of one hundred thousand years ('100k world'1). Ice core and ocean sediment data have shown that atmospheric carbon dioxide, Antarctic temperature, deep ocean temperature, and global ice volume correlated strongly with each...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/s41586-019-1692-3
更新日期:2019-10-01 00:00:00
abstract::Most patients with cancer either do not respond to immune checkpoint blockade or develop resistance to it, often because of acquired mutations that impair antigen presentation. Here we show that loss of function of the RNA-editing enzyme ADAR1 in tumour cells profoundly sensitizes tumours to immunotherapy and overcome...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/s41586-018-0768-9
更新日期:2019-01-01 00:00:00
abstract::The brain has generally been considered an insulin-independent organ, because insulin does not apparently exert a direct effect on brain glucose consumption. Recently, however, insulin receptors have been detected throughout the central nervous system (CNS) of several species. Since important insights into the functio...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/282623a0
更新日期:1979-12-06 00:00:00
abstract::Reinforcement learning models postulate that neurons that release dopamine encode information about action and action outcome, and provide a teaching signal to striatal spiny projection neurons in the form of dopamine release1. Dopamine is thought to guide learning via dynamic and differential modulation of protein ki...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/s41586-020-03050-5
更新日期:2020-12-23 00:00:00
abstract::The Axl receptor tyrosine kinase was identified as a protein encoded by a transforming gene from primary human myeloid leukaemia cells by DNA-mediated transformation of NIH 3T3 cells. Axl is the founding member of a family of related receptors that includes Eyk, encoded by a chicken proto-oncogene originally described...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/373623a0
更新日期:1995-02-16 00:00:00
abstract::Features that were once considered exclusive to modern birds, such as feathers and a furcula, are now known to have first appeared in non-avian dinosaurs. However, relatively little is known of the early evolutionary history of the hyperinflated brain that distinguishes birds from other living reptiles and provides th...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature12424
更新日期:2013-09-05 00:00:00
abstract::Metazoan gene regulation often involves the pausing of RNA polymerase II (Pol II) in the promoter-proximal region. Paused Pol II is stabilized by the protein complexes DRB sensitivity-inducing factor (DSIF) and negative elongation factor (NELF). Here we report the cryo-electron microscopy structure of a paused transcr...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/s41586-018-0442-2
更新日期:2018-08-01 00:00:00
abstract::It is known that glucose-induced depolarization of pancreatic B-cells is due to reduced membrane K+-permeability and is coupled to an increase in the rate of glycolysis, but there has been no direct evidence linking specific metabolic processes or products to the closing of membrane K+ channels. During patch-clamp stu...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/311271a0
更新日期:1984-09-20 00:00:00
abstract::The theory of reinforcement learning provides a normative account, deeply rooted in psychological and neuroscientific perspectives on animal behaviour, of how agents may optimize their control of an environment. To use reinforcement learning successfully in situations approaching real-world complexity, however, agents...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature14236
更新日期:2015-02-26 00:00:00
abstract::Microscopic diamond was recently discovered in oxidized acid residues from several carbonaceous chondrite meteorites (for example, the C delta component of the Allende meteorite). Some of the reported properties of C delta seem in conflict with those expected of diamond. Here we present high spatial resolution analy...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/332611a0
更新日期:1988-04-14 00:00:00
abstract::Caenorhabditis elegans senses environmental signals through ciliated sensory neurons located primarily in sensory organs in the head and tail. Cilia function as sensory receptors, and mutants with defective sensory cilia have impaired sensory perception. Cilia are membrane-bound microtubule-based structures and in C. ...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/45544
更新日期:1999-12-16 00:00:00
abstract::Three Hipparion trails, two from adults and one from a juvenile dating from about 3.5 Myr ago, have now been found in Laetoli. Comparison of the Hipparion footprints with a variety of imprints made by domestic horses showed that the animals moved with a running walk over the soft and slippery soil of Laetoli: in the a...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/308179a0
更新日期:1984-03-08 00:00:00
abstract::A mouse major histocompatibility antigen (H-2) gene, encoding a novel H-2Ld molecule lacking its intracytoplasmic domain, has been constructed and introduced into mouse L-cells. The novel H-2 molecule is found on the surface of the transfected cells at the same level as L-cells transfected with the native H-2Ld gene. ...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/307432a0
更新日期:1984-02-02 00:00:00
abstract::Quantum electrodynamics describes the interactions of electrons and photons. Electric charge (the gauge coupling constant) is energy dependent, and there is a previous claim that charge is affected by gravity (described by general relativity) with the implication that the charge is reduced at high energies. However, t...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature09506
更新日期:2010-11-04 00:00:00
abstract::Genes and mechanisms involved in common complex diseases, such as the autoimmune disorders that affect approximately 5% of the population, remain obscure. Here we identify polymorphisms of the cytotoxic T lymphocyte antigen 4 gene (CTLA4)--which encodes a vital negative regulatory molecule of the immune system--as can...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature01621
更新日期:2003-05-29 00:00:00
abstract::Many natural habitats exist on privately owned land outside protected areas, but few governments can afford to enforce or subsidize conservation of this biodiversity. Even in some developed countries, conservation subsidy schemes have only achieved limited success. Fortunately, some landowners may be willing to accept...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature01678
更新日期:2003-05-29 00:00:00
abstract::Tumour necrosis factor (TNF) elicits multiple biological effects through two distinct cell surface receptors, TNF-R1 (p55) and TNF-R2 (p75). Most TNF-mediated biological responses, such as cell death, gene induction, antiviral activity and cytokine production, have been attributed to TNF-R1 (refs 1-5). Gene targeting ...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/372560a0
更新日期:1994-12-08 00:00:00
abstract::Molecules capable of mimicking the function of a wide range of mechanical devices have been fabricated, with motors that can induce mechanical movement attracting particular attention. Such molecular motors convert light or chemical energy into directional rotary or linear motion, and are usually prepared and operated...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature04127
更新日期:2005-10-27 00:00:00
abstract::In vertebrates the developing hindbrain is organized in segmental units. These units provide the primary grid for differentiation and axonal outgrowth. In the more anterior regions of the brain, however, the subdivisions remain more controversial. Cellular and molecular studies of the embryonic brain in lower vertebra...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/353267a0
更新日期:1991-09-19 00:00:00