盖亚假说

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The study of planetary habitability is partly based upon extrapolation from knowledge of the Earth's conditions, as the Earth is the only planet currently known to harbour life (The Blue Marble, 1972 Apollo 17 photograph)

The study of planetary habitability is partly based upon extrapolation from knowledge of the Earth's conditions, as the Earth is the only planet currently known to harbour life (The Blue Marble, 1972 Apollo 17 photograph)

对行星适居性星球的研究部分是基于[地球的条件，因为地球是目前已知唯一存在生命的行星]的知识推断

The Gaia hypothesis 模板:IPAc-en, also known as the Gaia theory or the Gaia principle, proposes that living organisms interact with their inorganic surroundings on Earth to form a synergistic and self-regulating, complex system that helps to maintain and perpetuate the conditions for life on the planet.

The Gaia hypothesis , also known as the Gaia theory or the Gaia principle, proposes that living organisms interact with their inorganic surroundings on Earth to form a synergistic and self-regulating, complex system that helps to maintain and perpetuate the conditions for life on the planet.

盖亚假说(又称盖亚理论或盖亚原理)提出，生物体与地球上的无机环境相互作用，形成一个协同和自我调节的复杂系统，有助于维持和延续地球上的生命条件。

The hypothesis was formulated by the chemist James Lovelock and co-developed by the microbiologist Lynn Margulis in the 1970s. Lovelock named the idea after Gaia, the primordial goddess who personified the Earth in Greek mythology. In 2006, the Geological Society of London awarded Lovelock the Wollaston Medal in part for his work on the Gaia hypothesis.

The hypothesis was formulated by the chemist James Lovelock Lovelock named the idea after Gaia, the primordial goddess who personified the Earth in Greek mythology. In 2006, the Geological Society of London awarded Lovelock the Wollaston Medal in part for his work on the Gaia hypothesis.

这个假设是由化学家詹姆斯 · 洛夫洛克提出的，他以希腊神话中原始女神盖亚的名字命名这个想法。2006年，美国青草湖(韩国)学会授予洛夫洛克伍拉斯顿奖章，部分是因为他在盖亚假说方面的工作。

Topics related to the hypothesis include how the biosphere and the evolution of organisms affect the stability of global temperature, salinity of seawater, atmospheric oxygen levels, the maintenance of a hydrosphere of liquid water and other environmental variables that affect the habitability of Earth.

Topics related to the hypothesis include how the biosphere and the evolution of organisms affect the stability of global temperature, salinity of seawater, atmospheric oxygen levels, the maintenance of a hydrosphere of liquid water and other environmental variables that affect the habitability of Earth.

与该假设有关的主题包括生物圈和生物体的进化如何影响全球温度的稳定性、海水的盐度、大气中的氧含量、液态水的水圈的维持以及影响地球宜居性的其他环境变量。

The Gaia hypothesis was initially criticized for being teleological and against the principles of natural selection, but later refinements aligned the Gaia hypothesis with ideas from fields such as Earth system science, biogeochemistry and systems ecology. Lovelock also once described the "geophysiology" of the Earth.模板:Explain Even so, the Gaia hypothesis continues to attract criticism, and today many scientists consider it to be only weakly supported by, or at odds with, the available evidence.

The Gaia hypothesis was initially criticized for being teleological and against the principles of natural selection, but later refinements aligned the Gaia hypothesis with ideas from fields such as Earth system science, biogeochemistry and systems ecology. Lovelock also once described the "geophysiology" of the Earth. Even so, the Gaia hypothesis continues to attract criticism, and today many scientists consider it to be only weakly supported by, or at odds with, the available evidence.

盖亚假说最初被批评为目的论和反对自然选择的原则，但后来的改进使盖亚假说与来自地球系统科学、生物地球化学和系统生态学等领域的想法相一致。洛夫洛克还曾经描述过地球的“地球物理学”。即便如此，盖亚假说仍然受到批评，今天许多科学家认为它只有微弱的支持，或与现有的证据相矛盾。

Overview

Gaian hypotheses suggest that organisms co-evolve with their environment: that is, they "influence their abiotic environment, and that environment in turn influences the biota by Darwinian process". Lovelock (1995) gave evidence of this in his second book, showing the evolution from the world of the early thermo-acido-philic and methanogenic bacteria towards the oxygen-enriched atmosphere today that supports more complex life.

Gaian hypotheses suggest that organisms co-evolve with their environment: that is, they "influence their abiotic environment, and that environment in turn influences the biota by Darwinian process". Lovelock (1995) gave evidence of this in his second book, showing the evolution from the world of the early thermo-acido-philic and methanogenic bacteria towards the oxygen-enriched atmosphere today that supports more complex life.

盖亚假说认为，生物体与其环境共同进化: 也就是说，它们“影响其非生物环境，而环境又通过达尔文进化过程影响生物群”。Lovelock (1995)在他的第二本书中提供了证据，展示了从早期嗜热酸性和产甲烷细菌的世界到今天富氧大气支持更复杂的生命的进化。

A reduced version of the hypothesis has been called "influential Gaia" in "Directed Evolution of the Biosphere: Biogeochemical Selection or Gaia?" by Andrei G. Lapenis, which states the biota influence certain aspects of the abiotic world, e.g. temperature and atmosphere. This is not the work of an individual but a collective of Russian scientific research that was combined into this peer reviewed publication. It states the coevolution of life and the environment through “micro-forces” and biogeochemical processes. An example is how the activity of photosynthetic bacteria during Precambrian times completely modified the Earth atmosphere to turn it aerobic, and thus supports the evolution of life (in particular eukaryotic life).

A reduced version of the hypothesis has been called "influential Gaia" in "Directed Evolution of the Biosphere: Biogeochemical Selection or Gaia?" by Andrei G. Lapenis, which states the biota influence certain aspects of the abiotic world, e.g. temperature and atmosphere. This is not the work of an individual but a collective of Russian scientific research that was combined into this peer reviewed publication. It states the coevolution of life and the environment through “micro-forces”

在《生物圈的定向进化: 生物地球化学选择还是盖亚? 》一书中，这一假说的简化版被称为“有影响力的盖亚”由安德烈 · g · 拉佩尼斯所著，他指出生物群影响着非生物世界的某些方面，例如:。温度和大气。这不是一个人的工作，而是一个俄罗斯科学研究的集体，合并成这个同行评议的出版物。它通过“微观力量”阐述了生命与环境的共同进化

Since barriers existed throughout the twentieth century between Russia and the rest of the world, it is only relatively recently that the early Russian scientists who introduced concepts overlapping the Gaia hypothesis have become better known to the Western scientific community. These scientists include Piotr Alekseevich Kropotkin (1842–1921) (although he spent much of his professional life outside Russia), Vasil’evich Rizpolozhensky (1847–1918), Vladimir Ivanovich Vernadsky (1863–1945), and Vladimir Alexandrovich Kostitzin (1886–1963).

The Gaia hypothesis posits that the Earth is a self-regulating complex system involving the biosphere, the atmosphere, the hydrospheres and the pedosphere, tightly coupled as an evolving system. The hypothesis contends that this system as a whole, called Gaia, seeks a physical and chemical environment optimal for contemporary life.

盖亚假说认为，地球是一个自我调节的复杂系统，包括生物圈、大气层、水圈和土壤圈，作为一个进化的系统紧密结合在一起。这个假说认为，这个被称为盖亚的系统作为一个整体，寻求一个适合当代生命的物理和化学环境。

Biologists and Earth scientists usually view the factors that stabilize the characteristics of a period as an undirected emergent property or entelechy of the system; as each individual species pursues its own self-interest, for example, their combined actions may have counterbalancing effects on environmental change. Opponents of this view sometimes reference examples of events that resulted in dramatic change rather than stable equilibrium, such as the conversion of the Earth's atmosphere from a reducing environment to an oxygen-rich one at the end of the Archaean and the beginning of the Proterozoic periods.

Gaia evolves through a cybernetic feedback system operated unconsciously by the biota, leading to broad stabilization of the conditions of habitability in a full homeostasis. Many processes in the Earth's surface essential for the conditions of life depend on the interaction of living forms, especially microorganisms, with inorganic elements. These processes establish a global control system that regulates Earth's surface temperature, atmosphere composition and ocean salinity, powered by the global thermodynamic disequilibrium state of the Earth system.

盖亚通过一个由生物群无意识操作的控制论反馈系统进化，在一个完全的稳态中导致可居住条件的广泛稳定。地球表面的许多过程对生命的条件至关重要，这些过程依赖于生命形式，特别是微生物与无机元素的相互作用。这些过程建立了一个全球控制系统，由地球系统的全球热力学不平衡状态提供动力，调节地球表面温度、大气成分和海洋盐度。<！-- 提交给英国皇家学会的文章不是有效的参考文献。如果被接受，则必须用实际的文章引用替代，或者使用另一种引用 -- >

Less accepted versions of the hypothesis claim that changes in the biosphere are brought about through the coordination of living organisms and maintain those conditions through homeostasis. In some versions of Gaia philosophy, all lifeforms are considered part of one single living planetary being called Gaia. In this view, the atmosphere, the seas and the terrestrial crust would be results of interventions carried out by Gaia through the coevolving diversity of living organisms.

The existence of a planetary homeostasis influenced by living forms had been observed previously in the field of biogeochemistry, and it is being investigated also in other fields like Earth system science. The originality of the Gaia hypothesis relies on the assessment that such homeostatic balance is actively pursued with the goal of keeping the optimal conditions for life, even when terrestrial or external events menace them.

以前在生物地球化学领域已经观察到受生命形式影响的行星内稳态的存在，而且在地球系统科学等其他领域也在研究这一现象。盖亚假说的原创性依赖于这样一种评估: 即使地球或外部事件威胁到这种平衡，这种平衡也是为了保持生命的最佳状态而积极追求的。

The Gaia hypothesis was an influence on the deep ecology movement.

Details

Rob Rohde's palaeotemperature graphs

罗布 · 罗德的古温度图

The Gaia hypothesis posits that the Earth is a self-regulating complex system involving the biosphere, the atmosphere, the hydrospheres and the pedosphere, tightly coupled as an evolving system. The hypothesis contends that this system as a whole, called Gaia, seeks a physical and chemical environment optimal for contemporary life.

Since life started on Earth, the energy provided by the Sun has increased by 25% to 30%; however, the surface temperature of the planet has remained within the levels of habitability, reaching quite regular low and high margins. Lovelock has also hypothesised that methanogens produced elevated levels of methane in the early atmosphere, giving a view similar to that found in petrochemical smog, similar in some respects to the atmosphere on Titan. research has suggested that "oxygen shocks" and reduced methane levels led, during the Huronian, Sturtian and Marinoan/Varanger Ice Ages, to a world that very nearly became a solid "snowball". These epochs are evidence against the ability of the pre Phanerozoic biosphere to fully self-regulate.

自从地球上出现生命以来，太阳提供的能量增加了25% 至30% ; 然而，地球表面温度一直保持在可居住水平之内，达到了相当规则的低和高边缘。洛夫洛克还假设产甲烷菌在早期大气中产生了高浓度的甲烷，这与在石化烟雾中发现的观点相似，在某些方面与土卫六上的大气相似。研究表明，在休伦、斯图尔特和马里诺/瓦朗格冰河时期，“氧气冲击”和甲烷水平的降低，导致了一个几乎变成一个实心“雪球”的世界。这些时期是显生宙之前生物圈完全自我调节能力的证据。

Gaia evolves through a cybernetic feedback system operated unconsciously by the biota, leading to broad stabilization of the conditions of habitability in a full homeostasis. Many processes in the Earth's surface essential for the conditions of life depend on the interaction of living forms, especially microorganisms, with inorganic elements. These processes establish a global control system that regulates Earth's surface temperature, atmosphere composition and ocean salinity, powered by the global thermodynamic disequilibrium state of the Earth system.

Processing of the greenhouse gas CO₂, explained below, plays a critical role in the maintenance of the Earth temperature within the limits of habitability.

处理温室气体 CO < sub > 2 ，下面解释，在维持地球温度在可居住范围内起着关键作用。

The existence of a planetary homeostasis influenced by living forms had been observed previously in the field of biogeochemistry, and it is being investigated also in other fields like Earth system science. The originality of the Gaia hypothesis relies on the assessment that such homeostatic balance is actively pursued with the goal of keeping the optimal conditions for life, even when terrestrial or external events menace them.

The CLAW hypothesis, inspired by the Gaia hypothesis, proposes a feedback loop that operates between ocean ecosystems and the Earth's climate. The hypothesis specifically proposes that particular phytoplankton that produce dimethyl sulfide are responsive to variations in climate forcing, and that these responses lead to a negative feedback loop that acts to stabilise the temperature of the Earth's atmosphere.

受盖亚假说的启发，CLAW 假说提出了一个在海洋生态系统和地球气候之间运行的反馈回路。该假说特别提出，产生二甲硫醚的浮游植物对气候强迫的变化有反应，这些反应导致了一个负反馈循环，稳定了地球大气的温度。

Regulation of global surface temperature

Rob Rohde's palaeotemperature graphs

Currently the increase in human population and the environmental impact of their activities, such as the multiplication of greenhouse gases may cause negative feedbacks in the environment to become positive feedback. Lovelock has stated that this could bring an extremely accelerated global warming, but he has since stated the effects will likely occur more slowly.

目前，人口的增加及其活动对环境的影响，例如温室气体的增加，可能导致环境中的负反馈成为正反馈。洛夫洛克表示，这可能会极大地加速全球变暖，但他后来又表示，这种影响可能会发生得更慢。

See also: Paleoclimatology

Since life started on Earth, the energy provided by the Sun has increased by 25% to 30%; however, the surface temperature of the planet has remained within the levels of habitability, reaching quite regular low and high margins. Lovelock has also hypothesised that methanogens produced elevated levels of methane in the early atmosphere, giving a view similar to that found in petrochemical smog, similar in some respects to the atmosphere on Titan. This, he suggests tended to screen out ultraviolet until the formation of the ozone screen, maintaining a degree of homeostasis. However, the Snowball Earth research has suggested that "oxygen shocks" and reduced methane levels led, during the Huronian, Sturtian and Marinoan/Varanger Ice Ages, to a world that very nearly became a solid "snowball". These epochs are evidence against the ability of the pre Phanerozoic biosphere to fully self-regulate.

Plots from a standard black and white Daisyworld simulation

从一个标准的黑白图雏菊世界模拟

Processing of the greenhouse gas CO₂, explained below, plays a critical role in the maintenance of the Earth temperature within the limits of habitability.

In response to the criticism that the Gaia hypothesis seemingly required unrealistic group selection and cooperation between organisms, James Lovelock and Andrew Watson developed a mathematical model, Daisyworld, in which ecological competition underpinned planetary temperature regulation.

有人批评盖亚假说似乎需要不切实际的群体选择和有机体之间的合作，为了回应这种批评，詹姆斯 · 洛夫洛克和安德鲁 · 沃森建立了一个数学模型---- 雏菊世界，其中生态竞争支撑着地。

The CLAW hypothesis, inspired by the Gaia hypothesis, proposes a feedback loop that operates between ocean ecosystems and the Earth's climate. The hypothesis specifically proposes that particular phytoplankton that produce dimethyl sulfide are responsive to variations in climate forcing, and that these responses lead to a negative feedback loop that acts to stabilise the temperature of the Earth's atmosphere.

Daisyworld examines the energy budget of a planet populated by two different types of plants, black daisies and white daisies, which are assumed to occupy a significant portion of the surface. The colour of the daisies influences the albedo of the planet such that black daisies absorb more light and warm the planet, while white daisies reflect more light and cool the planet. The black daisies are assumed to grow and reproduce best at a lower temperature, while the white daisies are assumed to thrive best at a higher temperature. As the temperature rises closer to the value the white daisies like, the white daisies outreproduce the black daisies, leading to a larger percentage of white surface, and more sunlight is reflected, reducing the heat input and eventually cooling the planet. Conversely, as the temperature falls, the black daisies outreproduce the white daisies, absorbing more sunlight and warming the planet. The temperature will thus converge to the value at which the reproductive rates of the plants are equal.

《雏菊世界》调查了一个星球的能量预算，这个星球上生长着两种不同的植物，黑色雏菊和白色雏菊，这两种植物被认为占据了星球表面的很大一部分。雏菊的颜色影响了地球的反照率，黑色的雏菊吸收更多的光线，使地球变暖，而白色的雏菊则反射更多的光线，使地球变冷。人们认为黑色雏菊在较低的温度下生长和繁殖最好，而白色雏菊则被认为在较高的温度下生长最好。当温度上升到接近白色雏菊所喜欢的温度时，白色雏菊伸展出黑色雏菊，导致更大比例的白色表面，更多的阳光被反射，减少热量输入，最终使地球降温。相反，随着气温的下降，黑色雏菊长出了白色雏菊，吸收了更多的阳光，使地球变暖。因此，温度会收敛到植物繁殖率相等的值。

Currently the increase in human population and the environmental impact of their activities, such as the multiplication of greenhouse gases may cause negative feedbacks in the environment to become positive feedback. Lovelock has stated that this could bring an extremely accelerated global warming, but he has since stated the effects will likely occur more slowly.

Lovelock and Watson showed that, over a limited range of conditions, this negative feedback due to competition can stabilize the planet's temperature at a value which supports life, if the energy output of the Sun changes, while a planet without life would show wide temperature swings. The percentage of white and black daisies will continually change to keep the temperature at the value at which the plants' reproductive rates are equal, allowing both life forms to thrive.

洛夫洛克和沃森指出，在有限的条件下，如果太阳的能量输出发生变化，由于竞争而产生的负反馈可以将地球温度稳定在支持生命的数值上，而没有生命的地球则会表现出巨大的温度波动。白色和黑色雏菊的百分比会不断变化，以保持植物繁殖率相等的温度值，使两种生命形式都能茁壮成长。

Daisyworld simulations

Plots from a standard black and white Daisyworld simulation

It has been suggested that the results were predictable because Lovelock and Watson selected examples that produced the responses they desired.

有人认为，这些结果是可以预测的，因为洛夫洛克和沃森选择的例子产生了他们想要的答案。

Main article: Daisyworld

In response to the criticism that the Gaia hypothesis seemingly required unrealistic group selection and cooperation between organisms, James Lovelock and Andrew Watson developed a mathematical model, Daisyworld, in which ecological competition underpinned planetary temperature regulation.

Dry air in the atmosphere of Earth contains roughly (by volume) 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.039% carbon dioxide, and small amounts of other gases including methane. Lovelock originally speculated that concentrations of oxygen above about 25% would increase the frequency of wildfires and conflagration of forests. Recent work on the findings of fire-caused charcoal in Carboniferous and Cretaceous coal measures, in geologic periods when O₂ did exceed 25%, has supported Lovelock's contention.

地球大气层中的干燥空气大致(按体积计算)含有78.09% 的氮气、20.95% 的氧气、0.93% 的氩气、0.039% 的二氧化碳以及少量的其他气体，包括甲烷。洛夫洛克最初推测，高于25% 的氧气浓度会增加森林大火和森林大火的发生频率。最近在石炭纪和白垩纪煤系地质时期，o < sub > 2 确实超过了25% 的火成木炭的研究结果支持了 Lovelock 的论点。

Daisyworld examines the energy budget of a planet populated by two different types of plants, black daisies and white daisies, which are assumed to occupy a significant portion of the surface. The colour of the daisies influences the albedo of the planet such that black daisies absorb more light and warm the planet, while white daisies reflect more light and cool the planet. The black daisies are assumed to grow and reproduce best at a lower temperature, while the white daisies are assumed to thrive best at a higher temperature. As the temperature rises closer to the value the white daisies like, the white daisies outreproduce the black daisies, leading to a larger percentage of white surface, and more sunlight is reflected, reducing the heat input and eventually cooling the planet. Conversely, as the temperature falls, the black daisies outreproduce the white daisies, absorbing more sunlight and warming the planet. The temperature will thus converge to the value at which the reproductive rates of the plants are equal.

Lovelock and Watson showed that, over a limited range of conditions, this negative feedback due to competition can stabilize the planet's temperature at a value which supports life, if the energy output of the Sun changes, while a planet without life would show wide temperature swings. The percentage of white and black daisies will continually change to keep the temperature at the value at which the plants' reproductive rates are equal, allowing both life forms to thrive.

Gaia scientists see the participation of living organisms in the carbon cycle as one of the complex processes that maintain conditions suitable for life. The only significant natural source of atmospheric carbon dioxide (CO₂) is volcanic activity, while the only significant removal is through the precipitation of carbonate rocks. Carbon precipitation, solution and fixation are influenced by the bacteria and plant roots in soils, where they improve gaseous circulation, or in coral reefs, where calcium carbonate is deposited as a solid on the sea floor. Calcium carbonate is used by living organisms to manufacture carbonaceous tests and shells. Once dead, the living organisms' shells fall to the bottom of the oceans where they generate deposits of chalk and limestone.

盖亚的科学家们把生物体参与碳循环看作是维持适合生命条件的复杂过程之一。火山活动是大气中二氧化碳的唯一重要自然来源，而碳酸盐岩的沉淀是大气中二氧化碳唯一重要的去除途径。碳沉淀、溶解和固定受到土壤中细菌和植物根系的影响，这些细菌和植物根系可以改善气体循环，或者在珊瑚礁中，碳酸钙以固体的形式沉积在海底。碳酸钙被活的有机体用来制造含碳的试验和外壳。一旦死亡，生物体的外壳就会沉到海底，在那里它们产生白垩和石灰石的沉淀物。

It has been suggested that the results were predictable because Lovelock and Watson selected examples that produced the responses they desired.

One of these organisms is Emiliania huxleyi, an abundant coccolithophore algae which also has a role in the formation of clouds. CO₂ excess is compensated by an increase of coccolithophoride life, increasing the amount of CO₂ locked in the ocean floor. Coccolithophorides increase the cloud cover, hence control the surface temperature, help cool the whole planet and favor precipitations necessary for terrestrial plants. Lately the atmospheric CO₂ concentration has increased and there is some evidence that concentrations of ocean algal blooms are also increasing.

其中一种是赫氏圆石藻，这是一种数量丰富的颗石藻类，也参与了云的形成。CO < sub > 2 过量通过增加球石氟化物的寿命来补偿，增加了锁定在海底的 CO < sub > 2 的数量。球石粉会增加云量，从而控制地表温度，有助于降低整个地球的温度，有利于地球上植物所必需的降水。近年来，大气中 CO < < sub > 2 浓度有所增加，有证据表明，海洋藻华的浓度也在增加。

Regulation of oceanic salinity

Lichen and other organisms accelerate the weathering of rocks in the surface, while the decomposition of rocks also happens faster in the soil, thanks to the activity of roots, fungi, bacteria and subterranean animals. The flow of carbon dioxide from the atmosphere to the soil is therefore regulated with the help of living beings. When CO₂ levels rise in the atmosphere the temperature increases and plants grow. This growth brings higher consumption of CO₂ by the plants, who process it into the soil, removing it from the atmosphere.

地衣和其他生物加速了岩石表面的风化，而岩石在土壤中的分解也加快了，这要归功于根、真菌、细菌和地下动物的活动。因此，二氧化碳从大气层流向土壤的过程是在生物的帮助下进行调节的。当大气中 CO < < < < 水平升高时，温度升高，植物生长。这种生长会增加植物对二氧化碳的消耗，植物会将二氧化碳处理到土壤中，从大气中排出。

Ocean salinity has been constant at about 3.5% for a very long time. Salinity stability in oceanic environments is important as most cells require a rather constant salinity and do not generally tolerate values above 5%. The constant ocean salinity was a long-standing mystery, because no process counterbalancing the salt influx from rivers was known. Recently it was suggested that salinity may also be strongly influenced by seawater circulation through hot basaltic rocks, and emerging as hot water vents on mid-ocean ridges. However, the composition of seawater is far from equilibrium, and it is difficult to explain this fact without the influence of organic processes. One suggested explanation lies in the formation of salt plains throughout Earth's history. It is hypothesized that these are created by bacterial colonies that fix ions and heavy metals during their life processes.

In the biogeochemical processes of Earth, sources and sinks are the movement of elements. The composition of salt ions within our oceans and seas is: sodium (Na⁺), chlorine (Cl⁻), sulfate (SO₄²⁻), magnesium (Mg²⁺), calcium (Ca²⁺) and potassium (K⁺). The elements that comprise salinity do not readily change and are a conservative property of seawater. There are many mechanisms that change salinity from a particulate form to a dissolved form and back. The known sources of sodium i.e. salts are when weathering, erosion, and dissolution of rocks are transported into rivers and deposited into the oceans.

The Mediterranean Sea as being Gaia's kidney is found (here) by Kenneth J. Hsue, a correspondence author in 2001. The "desiccation" of the Mediterranean is the evidence of a functioning kidney. Earlier "kidney functions" were performed during the "deposition of the Cretaceous (South Atlantic), Jurassic (Gulf of Mexico), Permo-Triassic (Europe), Devonian (Canada), Cambrian/Precambrian (Gondwana) saline giants."

Earthrise taken from Apollo 8 on December 24, 1968

[1968年12月24日阿波罗8号拍摄的地出]

The idea of the Earth as an integrated whole, a living being, has a long tradition. The mythical Gaia was the primal Greek goddess personifying the Earth, the Greek version of "Mother Nature" (from Ge = Earth, and Aia =

地球作为一个完整的整体，一个有生命的存在，这个观念有着悠久的传统。神话中的盖亚是拟人化地球的原始希腊女神，是希腊版本的“自然母亲”(来自 Ge = 地球，和 Aia =

Regulation of oxygen in the atmosphere

PIE grandmother), or the Earth Mother. James Lovelock gave this name to his hypothesis after a suggestion from the novelist William Golding, who was living in the same village as Lovelock at the time (Bowerchalke, Wiltshire, UK). Golding's advice was based on Gea, an alternative spelling for the name of the Greek goddess, which is used as prefix in geology, geophysics and geochemistry. Later, the naturalist and explorer Alexander von Humboldt recognized the coevolution of living organisms, climate, and Earth's crust. His visionary pronouncements were not widely accepted in the West, and some decades later the Gaia hypothesis received the same type of initial resistance from the scientific community.

馅饼祖母) ，或地球母亲。小说家威廉•戈尔丁(William Golding)提出了这个假说，之后，詹姆斯•洛夫洛克(James Lovelock)给自己的假说起了这个名字。戈尔丁当时和洛夫洛克住在同一个村庄(威尔特郡鲍尔查克)。戈尔丁的建议是基于 Gea 的，Gea 是希腊女神名字的另一种拼写形式，在地质学、地球物理学和地球化学中被用作前缀。后来，自然主义者和探险家亚历山大·冯·洪堡认识到了生物体、气候和地壳的共同进化。他的远见卓识并没有被西方广泛接受，几十年后，盖亚假说也遭到了科学界同样的抵制。

Levels of gases in the atmosphere in 420,000 years of ice core data from Vostok, Antarctica research station. Current period is at the left.

See also: Geological history of oxygen

Also in the turn to the 20th century Aldo Leopold, pioneer in the development of modern environmental ethics and in the movement for wilderness conservation, suggested a living Earth in his biocentric or holistic ethics regarding land.

同样在20世纪之交，现代环境伦理学发展的先驱、荒野保护运动的先驱奥尔多 · 利奥波德在他的生物中心或整体的土地伦理学中提出了一个有生命的地球。

The Gaia hypothesis states that the Earth's atmospheric composition is kept at a dynamically steady state by the presence of life. The atmospheric composition provides the conditions that contemporary life has adapted to. All the atmospheric gases other than noble gases present in the atmosphere are either made by organisms or processed by them.

The stability of the atmosphere in Earth is not a consequence of chemical equilibrium. Oxygen is a reactive compound, and should eventually combine with gases and minerals of the Earth's atmosphere and crust. Oxygen only began to persist in the atmosphere in small quantities about 50 million years before the start of the Great Oxygenation Event. Since the start of the Cambrian period, atmospheric oxygen concentrations have fluctuated between 15% and 35% of atmospheric volume. Traces of methane (at an amount of 100,000 tonnes produced per year) should not exist, as methane is combustible in an oxygen atmosphere.

Later, other relationships such as sea creatures producing sulfur and iodine in approximately the same quantities as required by land creatures emerged and helped bolster the hypothesis.

后来出现了其他关系，例如海洋生物产生的硫和碘的数量与陆地生物所需的数量大致相同，这些都支持了这一假说。

Dry air in the atmosphere of Earth contains roughly (by volume) 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.039% carbon dioxide, and small amounts of other gases including methane. Lovelock originally speculated that concentrations of oxygen above about 25% would increase the frequency of wildfires and conflagration of forests. Recent work on the findings of fire-caused charcoal in Carboniferous and Cretaceous coal measures, in geologic periods when O₂ did exceed 25%, has supported Lovelock's contention.

In 1971 microbiologist Dr. Lynn Margulis joined Lovelock in the effort of fleshing out the initial hypothesis into scientifically proven concepts, contributing her knowledge about how microbes affect the atmosphere and the different layers in the surface of the planet. The American biologist had also awakened criticism from the scientific community with her advocacy of the theory on the origin of eukaryotic organelles and her contributions to the endosymbiotic theory, nowadays accepted. Margulis dedicated the last of eight chapters in her book, The Symbiotic Planet, to Gaia. However, she objected to the widespread personification of Gaia and stressed that Gaia is "not an organism", but "an emergent property of interaction among organisms". She defined Gaia as "the series of interacting ecosystems that compose a single huge ecosystem at the Earth's surface. Period". The book's most memorable "slogan" was actually quipped by a student of Margulis': "Gaia is just symbiosis as seen from space".

1971年，微生物学家 Lynn Margulis 博士加入了 Lovelock 的行列，努力将最初的假设充实为科学证明的概念，贡献了她关于微生物如何影响大气层和地球表面不同层次的知识。这位美国生物学家也唤醒了科学界的批评，因为她倡导真核细胞器起源的理论，以及她对美国共生发源学会的贡献，现在被接受了。玛格丽丝在她的书《共生星球》中将最后八章献给了盖亚。然而，她反对对盖亚的广泛拟人化，并强调盖亚“不是一个有机体” ，而是“有机体之间相互作用的一个新兴属性”。她将盖亚定义为“组成地球表面一个巨大生态系统的一系列相互作用的生态系统”。句号”。这本书最令人难忘的“口号”实际上是由马古利斯的一个学生打趣说的: “从太空看，盖亚只是共生而已。”。

Processing of CO₂

See also: Carbon cycle

James Lovelock called his first proposal the Gaia hypothesis but has also used the term Gaia theory. Lovelock states that the initial formulation was based on observation, but still lacked a scientific explanation. The Gaia hypothesis has since been supported by a number of scientific experiments and provided a number of useful predictions. In fact, wider research proved the original hypothesis wrong, in the sense that it is not life alone but the whole Earth system that does the regulating. The principal sponsor was the National Audubon Society. Speakers included James Lovelock, George Wald, Mary Catherine Bateson, Lewis Thomas, John Todd, Donald Michael, Christopher Bird, Thomas Berry, David Abram, Michael Cohen, and William Fields. Some 500 people attended.

詹姆斯 · 洛夫洛克称他的第一个提议为盖亚假说，但也使用了盖亚理论这个术语。洛夫洛克说，最初的提法是基于观察，但仍然缺乏科学的解释。盖亚假说从那以后得到了一些科学实验的支持，并提供了一些有用的预测。事实上，更广泛的研究证明了最初的假设是错误的，在这个意义上，不是生命本身，而是整个地球系统在调节。主要赞助者是奥杜邦学会。讲者包括 James Lovelock、 George Wald、 Mary Catherine Bateson、 Lewis Thomas、 John Todd、 Donald Michael、 Christopher Bird、 Thomas Berry、 David Abram、 Michael Cohen 和 William Fields。大约有500人参加。

Gaia scientists see the participation of living organisms in the carbon cycle as one of the complex processes that maintain conditions suitable for life. The only significant natural source of atmospheric carbon dioxide (CO₂) is volcanic activity, while the only significant removal is through the precipitation of carbonate rocks. Carbon precipitation, solution and fixation are influenced by the bacteria and plant roots in soils, where they improve gaseous circulation, or in coral reefs, where calcium carbonate is deposited as a solid on the sea floor. Calcium carbonate is used by living organisms to manufacture carbonaceous tests and shells. Once dead, the living organisms' shells fall to the bottom of the oceans where they generate deposits of chalk and limestone.

One of these organisms is Emiliania huxleyi, an abundant coccolithophore algae which also has a role in the formation of clouds. CO₂ excess is compensated by an increase of coccolithophoride life, increasing the amount of CO₂ locked in the ocean floor. Coccolithophorides increase the cloud cover, hence control the surface temperature, help cool the whole planet and favor precipitations necessary for terrestrial plants. Lately the atmospheric CO₂ concentration has increased and there is some evidence that concentrations of ocean algal blooms are also increasing.

In 1988, climatologist Stephen Schneider organised a conference of the American Geophysical Union. The first Chapman Conference on Gaia,

在1988年，气候学家史蒂芬·史奈德组织了一次美国美国地球物理联盟协会的会议。关于盖亚的第一次查普曼会议,

Lichen and other organisms accelerate the weathering of rocks in the surface, while the decomposition of rocks also happens faster in the soil, thanks to the activity of roots, fungi, bacteria and subterranean animals. The flow of carbon dioxide from the atmosphere to the soil is therefore regulated with the help of living beings. When CO₂ levels rise in the atmosphere the temperature increases and plants grow. This growth brings higher consumption of CO₂ by the plants, who process it into the soil, removing it from the atmosphere.

Lovelock and other Gaia-supporting scientists, however, did attempt to disprove the claim that the hypothesis is not scientific because it is impossible to test it by controlled experiment. For example, against the charge that Gaia was teleological, Lovelock and Andrew Watson offered the Daisyworld Model (and its modifications, above) as evidence against most of these criticisms.

然而，洛夫洛克和其他支持盖亚理论的科学家确实试图反驳这样一种说法，即这种假设不科学，因为不可能通过控制实验来检验它。例如，针对盖亚是目的论的指控，洛夫洛克和安德鲁 · 沃森提出了雏菊世界模型(及其修正，上文)作为反驳大多数这些批评的证据。

History

Lovelock was careful to present a version of the Gaia hypothesis that had no claim that Gaia intentionally or consciously maintained the complex balance in her environment that life needed to survive. It would appear that the claim that Gaia acts "intentionally" was a metaphoric statement in his popular initial book and was not meant to be taken literally. This new statement of the Gaia hypothesis was more acceptable to the scientific community. Most accusations of teleologism ceased, following this conference.

洛夫洛克谨慎地提出了盖亚假说的一个版本，该假说没有声称盖亚有意或有意地在她的环境中维持生命赖以生存的复杂平衡。看起来，盖亚“故意”行为的说法只是他那本广受欢迎的书中的一个比喻性陈述，并不是字面意义上的理解。这种对盖亚假说的新陈述更能为科学界所接受。在这次会议之后，大多数关于目的论的指责都停止了。

Precedents

Earthrise taken from Apollo 8 on December 24, 1968

By the time of the 2nd Chapman Conference on the Gaia Hypothesis, held at Valencia, Spain, on 23 June 2000, the situation had changed significantly. Rather than a discussion of the Gaian teleological views, or "types" of Gaia hypotheses, the focus was upon the specific mechanisms by which basic short term homeostasis was maintained within a framework of significant evolutionary long term structural change.

到2000年6月23日在西班牙巴伦西亚举行关于盖亚假说的第二次查普曼会议时，情况发生了重大变化。与其讨论盖亚的目的论观点，或盖亚假说的“类型” ，不如将重点放在具体的机制上，通过这些机制，基本的短期内稳态在一个重要的进化的长期结构变化的框架内得以维持。

The idea of the Earth as an integrated whole, a living being, has a long tradition. The mythical Gaia was the primal Greek goddess personifying the Earth, the Greek version of "Mother Nature" (from Ge = Earth, and Aia =

PIE grandmother), or the Earth Mother. James Lovelock gave this name to his hypothesis after a suggestion from the novelist William Golding, who was living in the same village as Lovelock at the time (Bowerchalke, Wiltshire, UK). Golding's advice was based on Gea, an alternative spelling for the name of the Greek goddess, which is used as prefix in geology, geophysics and geochemistry. Golding later made reference to Gaia in his Nobel prize acceptance speech.

The major questions were:

主要的问题是:

In the eighteenth century, as geology consolidated as a modern science, James Hutton maintained that geological and biological processes are interlinked. Later, the naturalist and explorer Alexander von Humboldt recognized the coevolution of living organisms, climate, and Earth's crust. In the twentieth century, Vladimir Vernadsky formulated a theory of Earth's development that is now one of the foundations of ecology. Vernadsky was a Ukrainian geochemist and was one of the first scientists to recognize that the oxygen, nitrogen, and carbon dioxide in the Earth's atmosphere result from biological processes. During the 1920s he published works arguing that living organisms could reshape the planet as surely as any physical force. Vernadsky was a pioneer of the scientific bases for the environmental sciences. His visionary pronouncements were not widely accepted in the West, and some decades later the Gaia hypothesis received the same type of initial resistance from the scientific community.

"How has the global biogeochemical/climate system called Gaia changed in time? What is its history? Can Gaia maintain stability of the system at one time scale but still undergo vectorial change at longer time scales? How can the geologic record be used to examine these questions?"

“被称为盖亚的全球生物地球化学/气候系统是如何及时发生变化的？它的历史是什么？盖亚能够在一个时间尺度上保持系统的稳定性，但是在更长的时间尺度上仍然经历矢量变化吗？如何利用地质记录来检验这些问题? ”

"What is the structure of Gaia? Are the feedbacks sufficiently strong to influence the evolution of climate? Are there parts of the system determined pragmatically by whatever disciplinary study is being undertaken at any given time or are there a set of parts that should be taken as most true for understanding Gaia as containing evolving organisms over time? What are the feedbacks among these different parts of the Gaian system, and what does the near closure of matter mean for the structure of Gaia as a global ecosystem and for the productivity of life?"

“盖亚的结构是什么？这些反馈是否足够强烈，足以影响气候的演变？系统的某些部分是由在任何特定时间进行的学科研究务实地决定的，还是有一些部分应该被认为是最真实的，以了解盖亚随着时间的推移包含进化中的生物体？盖亚系统这些不同部分之间的反馈是什么? 对盖亚作为全球生态系统的结构和生命的生产力来说，物质的近乎封闭意味着什么? ”

Also in the turn to the 20th century Aldo Leopold, pioneer in the development of modern environmental ethics and in the movement for wilderness conservation, suggested a living Earth in his biocentric or holistic ethics regarding land.

"How do models of Gaian processes and phenomena relate to reality and how do they help address and understand Gaia? How do results from Daisyworld transfer to the real world? What are the main candidates for "daisies"? Does it matter for Gaia theory whether we find daisies or not? How should we be searching for daisies, and should we intensify the search? How can Gaian mechanisms be investigated using process models or global models of the climate system that include the biota and allow for chemical cycling?"

“盖亚过程和现象的模型如何与现实相关，它们如何帮助解决和理解盖亚？Daisyworld 的成果如何转移到现实世界？什么是“雏菊”的主要候选人？我们发现雏菊与否对盖亚理论重要吗？我们应该怎样寻找雏菊，我们应该加紧寻找吗？如何利用气候系统的过程模型或全球模型(包括生物群并允许化学循环)来研究盖恩机制? ”

It is at least not impossible to regard the earth's parts—soil, mountains, rivers, atmosphere etc,—as organs or parts of organs of a coordinated whole, each part with its definite function. And if we could see this whole, as a whole, through a great period of time, we might perceive not only organs with coordinated functions, but possibly also that process of consumption as replacement which in biology we call metabolism, or growth. In such case we would have all the visible attributes of a living thing, which we do not realize to be such because it is too big, and its life processes too slow.

— 模板:Comma separated entries

In 1997, Tyler Volk argued that a Gaian system is almost inevitably produced as a result of an evolution towards far-from-equilibrium homeostatic states that maximise entropy production, and Kleidon (2004) agreed stating: "...homeostatic behavior can emerge from a state of MEP associated with the planetary albedo"; "...the resulting behavior of a biotic Earth at a state of MEP may well lead to near-homeostatic behavior of the Earth system on long time scales, as stated by the Gaia hypothesis". Staley (2002) has similarly proposed "...an alternative form of Gaia theory based on more traditional Darwinian principles... In [this] new approach, environmental regulation is a consequence of population dynamics, not Darwinian selection. The role of selection is to favor organisms that are best adapted to prevailing environmental conditions. However, the environment is not a static backdrop for evolution, but is heavily influenced by the presence of living organisms. The resulting co-evolving dynamical process eventually leads to the convergence of equilibrium and optimal conditions".

在1997年，Tyler Volk 认为盖亚系统几乎不可避免的产生作为一个进化到远离平衡的恒定状态的结果，最大限度地提高产生熵，Kleidon (2004)同意说: “ ... 恒定行为可以从与行星反照率有关的 MEP 状态出现” ; “ ... 生物地球在 MEP 状态下的结果行为很可能导致地球系统在长时间尺度上的近恒定行为，如盖亚假说所述。”。斯特利(2002)同样提出“ ... 盖亚理论的另一种形式基于更传统的达尔文原则..。在这种新方法中，环境管理是族群动态的结果，而不是达尔文的选择。选择的作用是使生物最适应当时的环境条件。然而，环境并不是进化的静态背景，而是受到生物体存在的严重影响。由此产生的共同演化动力学过程最终导致均衡和最优条件的收敛”。

Another influence for the Gaia hypothesis and the environmental movement in general came as a side effect of the Space Race between the Soviet Union and the United States of America. During the 1960s, the first humans in space could see how the Earth looked as a whole. The photograph Earthrise taken by astronaut William Anders in 1968 during the Apollo 8 mission became, through the Overview Effect an early symbol for the global ecology movement.

A fourth international conference on the Gaia hypothesis, sponsored by the Northern Virginia Regional Park Authority and others, was held in October 2006 at the Arlington, VA campus of George Mason University.

第四次关于盖亚假说的国际会议，由北弗吉尼亚地区公园管理局和其他机构主办，于2006年10月在弗吉尼亚州乔治梅森大学的阿灵顿校区举行。

Formulation of the hypothesis

James Lovelock, 2005

Martin Ogle, Chief Naturalist, for NVRPA, and long-time Gaia hypothesis proponent, organized the event. Lynn Margulis, Distinguished University Professor in the Department of Geosciences, University of Massachusetts-Amherst, and long-time advocate of the Gaia hypothesis, was a keynote speaker. Among many other speakers: Tyler Volk, Co-director of the Program in Earth and Environmental Science at New York University; Dr. Donald Aitken, Principal of Donald Aitken Associates; Dr. Thomas Lovejoy, President of the Heinz Center for Science, Economics and the Environment; Robert Correll, Senior Fellow, Atmospheric Policy Program, American Meteorological Society and noted environmental ethicist, J. Baird Callicott.

马丁奥格尔，首席自然主义者，为 NVRPA，和长期的盖亚假说支持者，组织了这次活动。麻省大学阿默斯特分校地球科学系杰出大学教授、长期倡导盖亚假说的 Lynn Margulis 是主题演讲者。其他演讲者包括: 纽约大学地球与环境科学项目联席主任 Tyler Volk; Donald Aitken Associates 校长 Donald Aitken 博士; Heinz Center for Science，Economics and the Environment 总裁 Thomas Lovejoy 博士; Robert Correll，环境伦理美国气象学会大气政策项目高级研究员，著名环境伦理学家 j. Baird Callicott。

Lovelock started defining the idea of a self-regulating Earth controlled by the community of living organisms in September 1965, while working at the Jet Propulsion Laboratory in California on methods of detecting life on Mars. The first paper to mention it was Planetary Atmospheres: Compositional and other Changes Associated with the Presence of Life, co-authored with C.E. Giffin. A main concept was that life could be detected in a planetary scale by the chemical composition of the atmosphere. According to the data gathered by the Pic du Midi observatory, planets like Mars or Venus had atmospheres in chemical equilibrium. This difference with the Earth atmosphere was considered to be a proof that there was no life in these planets.

This conference approached the Gaia hypothesis as both science and metaphor as a means of understanding how we might begin addressing 21st century issues such as climate change and ongoing environmental destruction.

这次会议将盖亚假说作为一种科学和隐喻的手段，来理解我们如何开始解决21世纪的问题，如气候变化和持续的环境破坏。

Lovelock formulated the Gaia Hypothesis in journal articles in 1972 and 1974, followed by a popularizing 1979 book Gaia: A new look at life on Earth. An article in the New Scientist of February 6, 1975, and a popular book length version of the hypothesis, published in 1979 as The Quest for Gaia, began to attract scientific and critical attention.

Lovelock called it first the Earth feedback hypothesis, and it was a way to explain the fact that combinations of chemicals including oxygen and methane persist in stable concentrations in the atmosphere of the Earth. Lovelock suggested detecting such combinations in other planets' atmospheres as a relatively reliable and cheap way to detect life.

After initially receiving little attention from scientists (from 1969 until 1977), thereafter for a period the initial Gaia hypothesis was criticized by a number of scientists, such as Ford Doolittle, Richard Dawkins and Stephen Jay Gould. Lovelock has said that because his hypothesis is named after a Greek goddess, and championed by many non-scientists, He wanted to know the actual mechanisms by which self-regulating homeostasis was achieved. In his defense of Gaia, David Abram argues that Gould overlooked the fact that "mechanism", itself, is a metaphor — albeit an exceedingly common and often unrecognized metaphor — one which leads us to consider natural and living systems as though they were machines organized and built from outside (rather than as autopoietic or self-organizing phenomena). Mechanical metaphors, according to Abram, lead us to overlook the active or agential quality of living entities, while the organismic metaphorics of the Gaia hypothesis accentuate the active agency of both the biota and the biosphere as a whole. With regard to causality in Gaia, Lovelock argues that no single mechanism is responsible, that the connections between the various known mechanisms may never be known, that this is accepted in other fields of biology and ecology as a matter of course, and that specific hostility is reserved for his own hypothesis for other reasons.

在最初几乎没有引起科学家的注意之后(从1969年到1977年) ，有一段时间，最初的盖亚假说受到了一些科学家的批评，如福特杜利特，理查德道金斯和史蒂芬·古尔德。洛夫洛克说，因为他的假说是以一位希腊女神的名字命名的，并得到许多非科学家的拥护，他想知道实现自我调节体内平衡的实际机制。在为盖亚辩护时，戴维•阿布拉姆(David Abram)认为，古尔德忽视了一个事实，即“机制”本身就是一个隐喻——尽管这个隐喻极其常见，而且往往不为人所知——这个隐喻让我们把自然和生命系统看作是由外部组织和建造的机器(而不是自动生成或自组织现象)。根据阿布拉姆的说法，机械隐喻使我们忽略了生命实体的活跃性或代表性，而盖亚假说的有机隐喻强调了生物群和整个生物圈的活跃性。关于盖亚的因果关系，洛夫洛克认为没有单一的机制是负责任的，各种已知机制之间的联系可能永远不会被人知道，这在生物学和生态学的其他领域是理所当然地被接受的，并且由于其他原因，特定的敌意是保留给他自己的假设的。

Lynn Margulis

Aside from clarifying his language and understanding of what is meant by a life form, Lovelock himself ascribes most of the criticism to a lack of understanding of non-linear mathematics by his critics, and a linearizing form of greedy reductionism in which all events have to be immediately ascribed to specific causes before the fact. He also states that most of his critics are biologists but that his hypothesis includes experiments in fields outside biology, and that some self-regulating phenomena may not be mathematically explainable.

除了澄清他的语言和理解什么是生命形式，洛夫洛克自己把大部分的批评归因于他的批评者缺乏对非线性数学的理解，以及贪婪还原主义的线性化形式，在这种形式中，所有事件都必须立即归因于事件发生之前的特定原因。他还表示，批评他的人大多是生物学家，但他的假设包括生物学以外领域的实验，以及一些自我调节现象可能无法在数学上解释。

Later, other relationships such as sea creatures producing sulfur and iodine in approximately the same quantities as required by land creatures emerged and helped bolster the hypothesis.

Evolutionary biologist W. D. Hamilton called the concept of Gaia Copernican, adding that it would take another Newton to explain how Gaian self-regulation takes place through Darwinian natural selection. More recently Ford Doolittle building on his and Inkpen's ITSNTS (It's The Singer Not The Song) proposal proposed that differential persistence can play a similar role to differential reproduction in evolution by natural selections, thereby providing a possible reconciliation between the theory of natural selection and the Gaia hypothesis.

进化生物学家 w · d · 汉密尔顿称盖亚 · 哥白尼的概念为“自我调节” ，并补充说，要解释盖亚的自我调节是如何通过达尔文的自然选择进行的，还需要另一个牛顿。最近，福特 · 杜利特尔在他和墨水笔的 ITSNTS (It’s The Singer Not The Song)提案的基础上提出，差异持续性在进化过程中可以通过自然选择发挥类似于差异繁殖的作用，从而为自然选择理论和盖亚假说之间的协调提供了可能。

In 1971 microbiologist Dr. Lynn Margulis joined Lovelock in the effort of fleshing out the initial hypothesis into scientifically proven concepts, contributing her knowledge about how microbes affect the atmosphere and the different layers in the surface of the planet. The American biologist had also awakened criticism from the scientific community with her advocacy of the theory on the origin of eukaryotic organelles and her contributions to the endosymbiotic theory, nowadays accepted. Margulis dedicated the last of eight chapters in her book, The Symbiotic Planet, to Gaia. However, she objected to the widespread personification of Gaia and stressed that Gaia is "not an organism", but "an emergent property of interaction among organisms". She defined Gaia as "the series of interacting ecosystems that compose a single huge ecosystem at the Earth's surface. Period". The book's most memorable "slogan" was actually quipped by a student of Margulis': "Gaia is just symbiosis as seen from space".

The Gaia hypothesis continues to be broadly skeptically received by the scientific community. For instance, arguments both for and against it were laid out in the journal Climatic Change in 2002 and 2003. A significant argument raised against it are the many examples where life has had a detrimental or destabilising effect on the environment rather than acting to regulate it. to "Suspended uncomfortably between tainted metaphor, fact, and false science, I prefer to leave Gaia firmly in the background" The CLAW hypothesis, In 2009 the Medea hypothesis was proposed: that life has highly detrimental (biocidal) impacts on planetary conditions, in direct opposition to the Gaia hypothesis.

盖亚假说继续受到科学界的广泛怀疑。例如，在2002年和2003年的《气候变化》杂志上，支持和反对这一观点的论据都有。反对它的一个重要论点是，有许多例子表明，生命对环境产生了有害或破坏稳定的影响，而不是采取行动加以规范。到“令人不安地悬挂在受污染的隐喻、事实和虚假的科学之间，我宁愿让盖亚坚定地处于背景之中”的爪假说，在2009年，美狄亚假说被提出: 生命对行星条件具有高度有害(生物灭绝)的影响，直接反对盖亚假说。

James Lovelock called his first proposal the Gaia hypothesis but has also used the term Gaia theory. Lovelock states that the initial formulation was based on observation, but still lacked a scientific explanation. The Gaia hypothesis has since been supported by a number of scientific experiments and provided a number of useful predictions. In fact, wider research proved the original hypothesis wrong, in the sense that it is not life alone but the whole Earth system that does the regulating.

In a 2013 book-length evaluation of the Gaia hypothesis considering modern evidence from across the various relevant disciplines, Toby Tyrrell concluded that: "I believe Gaia is a dead end. Its study has, however, generated many new and thought provoking questions. While rejecting Gaia, we can at the same time appreciate Lovelock's originality and breadth of vision, and recognise that his audacious concept has helped to stimulate many new ideas about the Earth, and to champion a holistic approach to studying it". Elsewhere he presents his conclusion "The Gaia hypothesis is not an accurate picture of how our world works". This statement needs to be understood as referring to the "strong" and "moderate" forms of Gaia—that the biota obeys a principle that works to make Earth optimal (strength 5) or favourable for life (strength 4) or that it works as a homeostatic mechanism (strength 3). The latter is the "weakest" form of Gaia that Lovelock has advocated. Tyrrell rejects it. However, he finds that the two weaker forms of Gaia—Coeveolutionary Gaia and Influential Gaia, which assert that there are close links between the evolution of life and the environment and that biology affects the physical and chemical environment—are both credible, but that it is not useful to use the term "Gaia" in this sense and that those two forms were already accepted and explained by the processes of natural selection and adaptation.

在2013年对盖亚假说的一本书长度的评估中，考虑了来自各个相关学科的现代证据，托比 · 泰瑞尔总结道: “我认为盖亚是一条死胡同。然而，它的研究产生了许多新的和发人深省的问题。在拒绝盖亚的同时，我们可以欣赏洛夫洛克的原创性和视野的宽广，并认识到他的大胆概念有助于激发许多关于地球的新想法，并倡导一种研究地球的整体方法”。在其他地方，他提出了自己的结论: “盖亚假说并不能准确描述我们的世界是如何运作的”。这种说法需要被理解为是指盖亚的“强”和“中等”形式ーー生物群遵循一个原则，即使地球处于最佳状态(强度5)或有利于生命(强度4) ，或者它作为一种自我稳定机制(强度3)。后者是洛夫洛克所提倡的盖亚的“最弱”形式。泰瑞尔拒绝了。然而，他发现两种较弱的盖亚形式—— coevefu吹的盖亚形式和 Influential 盖亚形式都是可信的，这两种形式都断言生命的进化与环境之间存在密切的联系，而且生物学影响着物理和化学环境，但是在这个意义上使用“盖亚”一词是没有用的，这两种形式已经被接受，并且通过自然选择和适应过程得到了解释。

First Gaia conference

In 1985, the first public symposium on the Gaia hypothesis, Is The Earth A Living Organism? was held at University of Massachusetts Amherst, August 1–6. The principal sponsor was the National Audubon Society. Speakers included James Lovelock, George Wald, Mary Catherine Bateson, Lewis Thomas, John Todd, Donald Michael, Christopher Bird, Thomas Berry, David Abram, Michael Cohen, and William Fields. Some 500 people attended.

Second Gaia conference

In 1988, climatologist Stephen Schneider organised a conference of the American Geophysical Union. The first Chapman Conference on Gaia, was held in San Diego, California on March 7, 1988.

During the "philosophical foundations" session of the conference, David Abram spoke on the influence of metaphor in science, and of the Gaia hypothesis as offering a new and potentially game-changing metaphorics, while James Kirchner criticised the Gaia hypothesis for its imprecision. Kirchner claimed that Lovelock and Margulis had not presented one Gaia hypothesis, but four -

• CoEvolutionary Gaia: that life and the environment had evolved in a coupled way. Kirchner claimed that this was already accepted scientifically and was not new.

• Homeostatic Gaia: that life maintained the stability of the natural environment, and that this stability enabled life to continue to exist.

• Geophysical Gaia: that the Gaia hypothesis generated interest in geophysical cycles and therefore led to interesting new research in terrestrial geophysical dynamics.

• Optimising Gaia: that Gaia shaped the planet in a way that made it an optimal environment for life as a whole. Kirchner claimed that this was not testable and therefore was not scientific.

Of Homeostatic Gaia, Kirchner recognised two alternatives. "Weak Gaia" asserted that life tends to make the environment stable for the flourishing of all life. "Strong Gaia" according to Kirchner, asserted that life tends to make the environment stable, to enable the flourishing of all life. Strong Gaia, Kirchner claimed, was untestable and therefore not scientific.

Lovelock and other Gaia-supporting scientists, however, did attempt to disprove the claim that the hypothesis is not scientific because it is impossible to test it by controlled experiment. For example, against the charge that Gaia was teleological, Lovelock and Andrew Watson offered the Daisyworld Model (and its modifications, above) as evidence against most of these criticisms. Lovelock said that the Daisyworld model "demonstrates that self-regulation of the global environment can emerge from competition amongst types of life altering their local environment in different ways".

Lovelock was careful to present a version of the Gaia hypothesis that had no claim that Gaia intentionally or consciously maintained the complex balance in her environment that life needed to survive. It would appear that the claim that Gaia acts "intentionally" was a metaphoric statement in his popular initial book and was not meant to be taken literally. This new statement of the Gaia hypothesis was more acceptable to the scientific community. Most accusations of teleologism ceased, following this conference.

Third Gaia conference

By the time of the 2nd Chapman Conference on the Gaia Hypothesis, held at Valencia, Spain, on 23 June 2000, the situation had changed significantly. Rather than a discussion of the Gaian teleological views, or "types" of Gaia hypotheses, the focus was upon the specific mechanisms by which basic short term homeostasis was maintained within a framework of significant evolutionary long term structural change.

The major questions were:

1. "How has the global biogeochemical/climate system called Gaia changed in time? What is its history? Can Gaia maintain stability of the system at one time scale but still undergo vectorial change at longer time scales? How can the geologic record be used to examine these questions?"

1. "What is the structure of Gaia? Are the feedbacks sufficiently strong to influence the evolution of climate? Are there parts of the system determined pragmatically by whatever disciplinary study is being undertaken at any given time or are there a set of parts that should be taken as most true for understanding Gaia as containing evolving organisms over time? What are the feedbacks among these different parts of the Gaian system, and what does the near closure of matter mean for the structure of Gaia as a global ecosystem and for the productivity of life?"

1. "How do models of Gaian processes and phenomena relate to reality and how do they help address and understand Gaia? How do results from Daisyworld transfer to the real world? What are the main candidates for "daisies"? Does it matter for Gaia theory whether we find daisies or not? How should we be searching for daisies, and should we intensify the search? How can Gaian mechanisms be investigated using process models or global models of the climate system that include the biota and allow for chemical cycling?"

In 1997, Tyler Volk argued that a Gaian system is almost inevitably produced as a result of an evolution towards far-from-equilibrium homeostatic states that maximise entropy production, and Kleidon (2004) agreed stating: "...homeostatic behavior can emerge from a state of MEP associated with the planetary albedo"; "...the resulting behavior of a biotic Earth at a state of MEP may well lead to near-homeostatic behavior of the Earth system on long time scales, as stated by the Gaia hypothesis". Staley (2002) has similarly proposed "...an alternative form of Gaia theory based on more traditional Darwinian principles... In [this] new approach, environmental regulation is a consequence of population dynamics, not Darwinian selection. The role of selection is to favor organisms that are best adapted to prevailing environmental conditions. However, the environment is not a static backdrop for evolution, but is heavily influenced by the presence of living organisms. The resulting co-evolving dynamical process eventually leads to the convergence of equilibrium and optimal conditions".

Fourth Gaia conference

A fourth international conference on the Gaia hypothesis, sponsored by the Northern Virginia Regional Park Authority and others, was held in October 2006 at the Arlington, VA campus of George Mason University.

Martin Ogle, Chief Naturalist, for NVRPA, and long-time Gaia hypothesis proponent, organized the event. Lynn Margulis, Distinguished University Professor in the Department of Geosciences, University of Massachusetts-Amherst, and long-time advocate of the Gaia hypothesis, was a keynote speaker. Among many other speakers: Tyler Volk, Co-director of the Program in Earth and Environmental Science at New York University; Dr. Donald Aitken, Principal of Donald Aitken Associates; Dr. Thomas Lovejoy, President of the Heinz Center for Science, Economics and the Environment; Robert Correll, Senior Fellow, Atmospheric Policy Program, American Meteorological Society and noted environmental ethicist, J. Baird Callicott.

This conference approached the Gaia hypothesis as both science and metaphor as a means of understanding how we might begin addressing 21st century issues such as climate change and ongoing environmental destruction.

Criticism

After initially receiving little attention from scientists (from 1969 until 1977), thereafter for a period the initial Gaia hypothesis was criticized by a number of scientists, such as Ford Doolittle, Richard Dawkins and Stephen Jay Gould. Lovelock has said that because his hypothesis is named after a Greek goddess, and championed by many non-scientists, the Gaia hypothesis was interpreted as a neo-Pagan religion. Many scientists in particular also criticised the approach taken in his popular book Gaia, a New Look at Life on Earth for being teleological—a belief that things are purposeful and aimed towards a goal. Responding to this critique in 1990, Lovelock stated, "Nowhere in our writings do we express the idea that planetary self-regulation is purposeful, or involves foresight or planning by the biota".

Stephen Jay Gould criticised Gaia as being "a metaphor, not a mechanism." He wanted to know the actual mechanisms by which self-regulating homeostasis was achieved. In his defense of Gaia, David Abram argues that Gould overlooked the fact that "mechanism", itself, is a metaphor — albeit an exceedingly common and often unrecognized metaphor — one which leads us to consider natural and living systems as though they were machines organized and built from outside (rather than as autopoietic or self-organizing phenomena). Mechanical metaphors, according to Abram, lead us to overlook the active or agential quality of living entities, while the organismic metaphorics of the Gaia hypothesis accentuate the active agency of both the biota and the biosphere as a whole. With regard to causality in Gaia, Lovelock argues that no single mechanism is responsible, that the connections between the various known mechanisms may never be known, that this is accepted in other fields of biology and ecology as a matter of course, and that specific hostility is reserved for his own hypothesis for other reasons.

Aside from clarifying his language and understanding of what is meant by a life form, Lovelock himself ascribes most of the criticism to a lack of understanding of non-linear mathematics by his critics, and a linearizing form of greedy reductionism in which all events have to be immediately ascribed to specific causes before the fact. He also states that most of his critics are biologists but that his hypothesis includes experiments in fields outside biology, and that some self-regulating phenomena may not be mathematically explainable.

Natural selection and evolution

Lovelock has suggested that global biological feedback mechanisms could evolve by natural selection, stating that organisms that improve their environment for their survival do better than those that damage their environment. However, in the early 1980s, W. Ford Doolittle and Richard Dawkins separately argued against this aspect of Gaia. Doolittle argued that nothing in the genome of individual organisms could provide the feedback mechanisms proposed by Lovelock, and therefore the Gaia hypothesis proposed no plausible mechanism and was unscientific. Dawkins meanwhile stated that for organisms to act in concert would require foresight and planning, which is contrary to the current scientific understanding of evolution. Like Doolittle, he also rejected the possibility that feedback loops could stabilize the system.

Lynn Margulis, a microbiologist who collaborated with Lovelock in supporting the Gaia hypothesis, argued in 1999, that "Darwin's grand vision was not wrong, only incomplete. In accentuating the direct competition between individuals for resources as the primary selection mechanism, Darwin (and especially his followers) created the impression that the environment was simply a static arena". She wrote that the composition of the Earth's atmosphere, hydrosphere, and lithosphere are regulated around "set points" as in homeostasis, but those set points change with time.

Evolutionary biologist W. D. Hamilton called the concept of Gaia Copernican, adding that it would take another Newton to explain how Gaian self-regulation takes place through Darwinian natural selection.模板:Better source More recently Ford Doolittle building on his and Inkpen's ITSNTS (It's The Singer Not The Song) proposal proposed that differential persistence can play a similar role to differential reproduction in evolution by natural selections, thereby providing a possible reconciliation between the theory of natural selection and the Gaia hypothesis.

Criticism in the 21st century

The Gaia hypothesis continues to be broadly skeptically received by the scientific community. For instance, arguments both for and against it were laid out in the journal Climatic Change in 2002 and 2003. A significant argument raised against it are the many examples where life has had a detrimental or destabilising effect on the environment rather than acting to regulate it. Several recent books have criticised the Gaia hypothesis, expressing views ranging from "... the Gaia hypothesis lacks unambiguous observational support and has significant theoretical difficulties" to "Suspended uncomfortably between tainted metaphor, fact, and false science, I prefer to leave Gaia firmly in the background" to "The Gaia hypothesis is supported neither by evolutionary theory nor by the empirical evidence of the geological record". The CLAW hypothesis, initially suggested as a potential example of direct Gaian feedback, has subsequently been found to be less credible as understanding of cloud condensation nuclei has improved. In 2009 the Medea hypothesis was proposed: that life has highly detrimental (biocidal) impacts on planetary conditions, in direct opposition to the Gaia hypothesis.

In a 2013 book-length evaluation of the Gaia hypothesis considering modern evidence from across the various relevant disciplines, Toby Tyrrell concluded that: "I believe Gaia is a dead end. Its study has, however, generated many new and thought provoking questions. While rejecting Gaia, we can at the same time appreciate Lovelock's originality and breadth of vision, and recognise that his audacious concept has helped to stimulate many new ideas about the Earth, and to champion a holistic approach to studying it". Elsewhere he presents his conclusion "The Gaia hypothesis is not an accurate picture of how our world works". This statement needs to be understood as referring to the "strong" and "moderate" forms of Gaia—that the biota obeys a principle that works to make Earth optimal (strength 5) or favourable for life (strength 4) or that it works as a homeostatic mechanism (strength 3). The latter is the "weakest" form of Gaia that Lovelock has advocated. Tyrrell rejects it. However, he finds that the two weaker forms of Gaia—Coeveolutionary Gaia and Influential Gaia, which assert that there are close links between the evolution of life and the environment and that biology affects the physical and chemical environment—are both credible, but that it is not useful to use the term "Gaia" in this sense and that those two forms were already accepted and explained by the processes of natural selection and adaptation.

Category:Cybernetics

类别: 控制论

Category:Ecological theories

范畴: 生态学理论

See also

Category:Superorganisms

类别: 超级有机体

Category:Climate change feedbacks

类别: 气候变化反馈

Category:1965 introductions

类别: 1965年引言

• 模板:Annotated link

Category:Biogeochemistry

类别: 生物地球化学

• 模板:Annotated link

Category:Earth

类别: 地球

• 模板:Annotated link

Category:Biological hypotheses

类别: 生物学假说

• 模板:Annotated link

Category:Astronomical hypotheses

类别: 天文学假设

• 模板:Annotated link

Category:Meteorological hypotheses

类别: 气象假说

This page was moved from wikipedia:en:Gaia hypothesis. Its edit history can be viewed at 盖亚假说/edithistory