Geology of Venus

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Radar global map of the surface of Venus

 

The hemispheric view of Venus, as revealed by more than a decade of radar investigations culminating in the 1990–1994 Magellan mission, is centered at 180 degrees east longitude.

Venus is a planet with striking geology. Of all the other planets in the Solar System, it is the one nearest to Earth and most like it in terms of mass, but has no magnetic field or recognizable plate tectonic system. Much of the ground surface is exposed volcanic bedrock, some with thin and patchy layers of soil covering, in marked contrast with Earth, the Moon, and Mars. Some impact craters are present, but Venus is similar to Earth in that there are fewer craters than on the other rocky planets that are largely covered by them. This is due in part to the thickness of the Venusian atmosphere disrupting small impactors before they strike the ground, but the paucity of large craters may be due to volcanic re-surfacing, possibly of a catastrophic nature. Volcanism appears to be the dominant agent of geological change on Venus. Some of the volcanic landforms appear to be unique to the planet. There are shield and composite volcanoes similar to those found on Earth. Given that Venus has approximately the same size, density, and composition as Earth, it is plausible that volcanism may be continuing on the planet today, as demonstrated by recent studies.

Most of the Venusian surface is relatively flat; it is divided into three topographic units: lowlands, highlands, and plains. In the early days of radar observation the highlands drew comparison to the continents of Earth, but modern research has shown that this is superficial and the absence of plate tectonics makes this comparison misleading. Tectonic features are present to a limited extent, including linear "deformation belts" composed of folds and faults. These may be caused by mantle convection. Many of the tectonic features such as tesserae (large regions of highly deformed terrain, folded and fractured in two or three dimensions), and arachnoids (for those features resembling a spider's web) are associated with volcanism.

Eolian landforms are not widespread on the planet's surface, but there is considerable evidence the planet's atmosphere causes the chemical weathering of rock, especially at high elevations. The planet is remarkably dry, with only a chemical trace of water vapor (20 ppm) in the Venusian atmosphere. No landforms indicative of past water or ice are visible in radar images of the surface. The atmosphere shows isotopic evidence of having been stripped of volatile elements by offgassing and solar wind erosion over time, implying the possibility that Venus may have had liquid water at some point in the distant past; no direct evidence for this has been found. Much speculation about the geological history of Venus continues today.

The surface of Venus is not easily accessible because of the extremely thick atmosphere (some 90 times that of Earth's) and the 470 °C (878 °F) surface temperature. Much of what is known about it stems from orbital radar observations, because the surface is permanently obscured in visible wavelengths by cloud cover. In addition, a number of landers have returned data from the surface, including images.

Topography

Venus topography

 

Main article: Mapping of Venus

The surface of Venus is comparatively flat. When 93% of the topography was mapped by Pioneer Venus Orbiter, scientists found that the total distance from the lowest point to the highest point on the entire surface was about 13 kilometres (8.1 mi), about the same as the vertical distance between the Earth's ocean floor and the higher summits of the Himalayas. This similarity is to be expected as the maximum attainable elevation contrasts on a planet are largely dictated by the strength of the planet's gravity and the mechanical strength of its lithosphere, these are similar for Earth and Venus.

According to data from the Pioneer Venus Orbiter altimeters, nearly 51% of the surface is located within 500 meters (1,600 feet) of the median radius of 6,052 km (3,761 mi); only 2% of the surface is located at elevations greater than 2 kilometres (1.2 mi) from the median radius.

The altimetry experiment of Magellan confirmed the general character of the landscape. According to the Magellan data, 80% of the topography is within 1 km (0.62 mi) of the median radius. The most important elevations are in the mountain chains that surround Lakshmi Planum: Maxwell Montes (11 km, 6.8 mi), Akna Montes (7 km, 4.3 mi) and Freya Montes (7 km, 4.3 mi). Despite the relatively flat landscape of Venus, the altimetry data also found large inclined plains. Such is the case on the southwest side of Maxwell Montes, which in some parts seems to be inclined some 45°. Inclinations of 30° were registered in Danu Montes and Themis Regio.

About 75% of the surface is composed of bare rock.

Based on altimeter data from the Pioneer Venus Orbiter probe, supported by Magellan data, the topography of the planet is divided into three provinces: lowlands, deposition plains, and highlands.

Highlands

Aphrodite Terra topography

This unit covers about 10% of the planet's surface, with elevations greater than 2 km (1.2 mi). The largest provinces of the highlands are Aphrodite Terra, Ishtar Terra, and Lada Terra, as well as the regions Beta Regio, Phoebe Regio and Themis Regio. The regions Alpha Regio, Bell Regio, Eistla Regio and Tholus Regio are smaller regions of highlands.

Some of the terrain in these areas is particularly efficient at reflecting radar signals. This is possibly analogous to snow lines on Earth and is likely related to temperatures and pressures there being lower than in the other provinces due to the higher elevation, which allows for distinct mineralogy to occur. It is thought that high-elevation rock formations may contain or be coated by minerals that have high dielectric constants. The high dielectric minerals would be stable at the ambient temperatures in the highlands, but not on the plains that comprise the rest of the planet's surface. Pyrite, an iron sulfide, matches these criteria and is widely suspected as a possible cause; it would be produced by chemical weathering of the volcanic highlands after long-term exposure to the sulfur-bearing Venusian atmosphere. The presence of pyrite on Venus has been contested, with atmospheric modeling showing that it might not be stable under Venusian atmospheric conditions. Other hypotheses have been put forward to explain the higher radar reflectivity in the highlands, including the presence of a ferroelectric material whose dielectric constant changes with temperature (with Venus having a changing temperature gradient with elevation). It has been observed that the character of the radar-bright highlands is not consistent across the surface of Venus. For example, Maxwell Montes shows the sharp, snow line-like change in reflectivity that is consistent with a change in mineralogy, whereas Ovda Regio shows a more gradual brightening upwards trend. The brightening upwards trend on Ovda Regio is consistent with a ferroelectric signature, and has been suggested to indicate the presence of chlorapatite.

Deposition plains

Deposition plains have elevations averaging 0 to 2 km and cover more than half of the planet's surface.

Lowlands

The rest of the surface is lowlands and generally lies below zero elevation. Radar reflectivity data suggest that at a centimeter scale these areas are smooth, as a result of gradation (accumulation of fine material eroded from the highlands).

Surface observations

Ten spacecraft have successfully landed on Venus and returned data, all were flown by the Soviet Union. Venera 9, 10, 13, and 14 had cameras and returned images of soil and rock. Spectrophotometry results showed that these four missions kicked up dust clouds on landing, which means that some of the dust particles must be smaller than about 0.02 mm. The rocks at all four sites showed fine layers, some layers were more reflective than others. Experiments on rocks at the Venera 13 and 14 sites found that they were porous and easily crushed (bearing maximum loads of 0.3 to 1 MPa) these rocks may be weakly lithified sediments or volcanic tuff. Spectrometry found that the surface materials at the Venera 9, 10, 14 and Vega 1 and 2 landing had chemical compositions similar to tholeiitic basalts, while the Venera 8 and 13 sites chemically resembled alkaline basalts.

Impact craters and age estimates of the surface

Radar image of Danilova crater in relief

Earth-based radar surveys made it possible to identify some topographic patterns related to craters, and the Venera 15 and Venera 16 probes identified almost 150 such features of probable impact origin. Global coverage from Magellan subsequently made it possible to identify nearly 900 impact craters.

Danilova, Aglaonice and Saskja craters

Compared to Mercury, the Moon and other such bodies, Venus has very few craters. In part, this is because Venus's dense atmosphere burns up smaller meteorites before they hit the surface. The Venera and Magellan data are in agreement: there are very few impact craters with a diameter less than 30 kilometres (19 mi), and data from Magellan show an absence of any craters less than 2 kilometres (1.2 mi) in diameter. The small craters are irregular and appear in groups, thus pointing to the deceleration and the breakup of impactors. However, there are also fewer of the large craters, and those appear relatively young; they are rarely filled with lava, showing that they were formed after volcanic activity in the area ceased, and radar data indicates that they are rough and have not had time to be eroded down.

Compared to the situation on bodies such as the Moon, it is more difficult to determine the ages of different areas of the surface on Venus, on the basis of crater counts, due to the small number of craters at hand. However, the surface characteristics are consistent with a completely random distribution, implying that the surface of the entire planet is roughly the same age, or at least that very large areas are not very different in age from the average.

Taken together, this evidence suggests that the surface of Venus is geologically young. The impact crater distribution appears to be most consistent with models that call for a near-complete resurfacing of the planet. Subsequent to this period of extreme activity, process rates declined and impact craters began to accumulate, with only minor modification and resurfacing since.

A young surface all created at the same time is a different situation compared with any of the other terrestrial planets.

Global resurfacing event

Age estimates based on crater counts indicate a young surface, in contrast to the much older surfaces of Mars, Mercury, and the Moon. For this to be the case on a planet without crustal recycling by plate tectonics requires explanation. One hypothesis is that Venus underwent some sort of global resurfacing about 300–500 million years ago that erased the evidence of older craters.

One possible explanation for this event is that it is part of a cyclic process on Venus. On Earth, plate tectonics allows heat to escape from the mantle by advection, the transport of mantle material to the surface and the return of old crust to the mantle. But Venus has no evidence of plate tectonics, so this theory states that the interior of the planet heats up (due to the decay of radioactive elements) until material in the mantle is hot enough to force its way to the surface. The subsequent resurfacing event covers most or all of the planet with lava, until the mantle is cool enough for the process to start over.

Volcanoes

Main article: Volcanism on Venus

 

Radar image of pancake domes in Venus's Eistla region. The two larger ones are approximately 65 km (40 mi) wide and rise less than 1 km (0.62 mi) above the surrounding plain. These wide and fairly low, flat-topped volcanoes are a type of landform that is unique to Venus. They were probably formed by extrusions of highly viscous lava that was too sticky to flow very far down-slope from their vents.

 

Computer generated perspective view of pancake domes in Venus's Alpha Regio. The domes in this image average 25 km in diameter.

 

Arachnoid surface feature on Venus

The surface of Venus is dominated by volcanism. Although Venus is superficially similar to Earth, it seems that the tectonic plates so active in Earth's geology do not exist on Venus. About 80% of the planet consists of a mosaic of volcanic lava plains, dotted with more than a hundred large isolated shield volcanoes, and many hundreds of smaller volcanoes and volcanic constructs such as coronae. These are geological features believed to be almost unique to Venus: huge, ring-shaped structures 100–300 kilometers (62–186 miles) across and rising hundreds of meters above the surface. The only other place they have been discovered is on Uranus's moon Miranda. It is believed that they are formed when plumes of rising hot material in the mantle push the crust upwards into a dome shape, which then collapses in the centre as the molten lava cools and leaks out at the sides, leaving a crown-like structure: the corona.

Differences can be seen in volcanic deposits. In many cases, volcanic activity is localized to a fixed source, and deposits are found in the vicinity of this source. This kind of volcanism is called "centralized volcanism," in that volcanoes and other geographic features form distinct regions. The second type of volcanic activity is not radial or centralized; flood basalts cover wide expanses of the surface, similar to features such as the Deccan Traps on Earth. These eruptions result in "flow type" volcanoes.

Volcanoes less than 20 kilometres (12 mi) in diameter are very abundant on Venus and they may number hundreds of thousands or even millions. Many appear as flattened domes or 'pancakes', thought to be formed in a similar way to shield volcanoes on Earth. These pancake dome volcanoes are fairly round features that are less than 1-kilometre (0.62 mi) in height and many times that in width. It is common to find groups of hundreds of these volcanoes in areas called shield fields. The domes of Venus are between 10 and 100 times larger than those formed on Earth. They are usually associated with "coronae" and tesserae. The pancakes are thought to be formed by highly viscous, silica-rich lava erupting under Venus's high atmospheric pressure. Domes called scalloped margin domes (commonly called ticks because they appear as domes with numerous legs), are thought to have undergone mass wasting events such as landslides on their margins. Sometimes deposits of debris can be seen scattered around them.

On Venus, volcanoes are mainly of the shield type. Nevertheless, the morphology of the shield volcanoes of Venus is different from shield volcanoes on Earth. On the Earth, shield volcanoes can be a few tens of kilometers wide and up to 10 kilometers high (6.2 mi) in the case of Mauna Kea, measured from the sea floor. On Venus, these volcanoes can cover hundreds of kilometers in area, but they are relatively flat, with an average height of 1.5 kilometres (0.93 mi).

Other unique features of Venus's surface are novae (radial networks of dikes or grabens) and arachnoids. A nova is formed when large quantities of magma are extruded onto the surface to form radiating ridges and trenches which are highly reflective to radar. These dikes form a symmetrical network around the central point where the lava emerged, where there may also be a depression caused by the collapse of the magma chamber.

Arachnoids are so named because they resemble a spider's web, featuring several concentric ovals surrounded by a complex network of radial fractures similar to those of a nova. It is not known whether the 250 or so features identified as arachnoids actually share a common origin, or are the result of different geological processes.

Tectonic activity

Despite the fact that Venus appears to have no global plate tectonic system as such, the planet's surface shows various features associated with local tectonic activity. Features such as faults, folds, and volcanoes are present there and may be driven largely by processes in the mantle.

The active volcanism of Venus has generated chains of folded mountains, rift valleys, and terrain known as tesserae, a word meaning "floor tiles" in Greek. Tesserae exhibit the effects of eons of compression and tensional deformation.

Unlike those on Earth, the deformations on Venus are directly related to regional dynamic forces within the planet's mantle. Gravitational studies suggest that Venus differs from Earth in lacking an asthenosphere—a layer of lower viscosity and mechanical weakness that allows Earth's crustal tectonic plates to move. The apparent absence of this layer on Venus suggests that the deformation of the Venusian surface must be explained by convective movements within the planet's mantle.

The tectonic deformations on Venus occur on a variety of scales, the smallest of which are related to linear fractures or faults. In many areas these faults appear as networks of parallel lines. Small, discontinuous mountain crests are found which resemble those on the Moon and Mars. The effects of extensive tectonism are shown by the presence of normal faults, where the crust has sunk in one area relative to the surrounding rock, and superficial fractures. Radar imaging shows that these types of deformation are concentrated in belts located in the equatorial zones and at high southern latitudes. These belts are hundreds of kilometers wide and appear to interconnect across the whole of the planet, forming a global network associated with the distribution of volcanoes.

The rifts of Venus, formed by the expansion of the lithosphere, are groups of depressions tens to hundreds of meters wide and extending up to 1,000 km (620 mi) in length. The rifts are mostly associated with large volcanic elevations in the form of domes, such as those at Beta Regio, Atla Regio and the western part of Eistla Regio. These highlands seem to be the result of enormous mantle plumes (rising currents of magma) which have caused elevation, fracturing, faulting, and volcanism.

The highest mountain chain on Venus, Maxwell Montes in Ishtar Terra, was formed by processes of compression, expansion, and lateral movement. Another type of geographical feature, found in the lowlands, consists of ridge belts elevated several meters above the surface, hundreds of kilometers wide and thousands of kilometers long. Two major concentrations of these belts exist: one in Lavinia Planitia near the southern pole, and the second adjacent to Atalanta Planitia near the northern pole.

Tesserae are found mainly in Aphrodite Terra, Alpha Regio, Tellus Regio and the eastern part of Ishtar Terra (Fortuna Tessera). These regions contain the superimposition and intersection of grabens of different geological units, indicating that these are the oldest parts of the planet. It was once thought that the tesserae were continents associated with tectonic plates like those of the Earth; in reality they are probably the result of floods of basaltic lava forming large plains, which were then subjected to intense tectonic fracturing.

Cutaway diagram of possible internal structure

Magnetic field and internal structure

Venus's crust appears to be 70 kilometres (43 mi) thick, and composed of silicate rocks. Venus's mantle is approximately 2,840 kilometres (1,760 mi) thick, its chemical composition is probably similar to that of chondrites. Since Venus is a terrestrial planet, it is presumed to have a core made of semisolid iron and nickel with a radius of approximately 3,000 kilometres (1,900 mi).

The unavailability of seismic data from Venus severely limits what can be definitely known about the structure of the planet's mantle, but models of Earth's mantle have been modified to make predictions. It's expected that the uppermost mantle, from about 70 to 480 kilometres (43 to 298 mi) deep is mostly made of the mineral olivine. Descending through the mantle, the chemical composition remains largely the same but at somewhere between about 480 and 760 kilometres (300 and 470 mi), the increasing pressure causes the crystal structure of olivine to change to the more densely packed structure of spinel. Another transition occurs between 760 and 1,000 kilometres (470 and 620 mi) deep, where the material takes on the progressively more compact crystal structures of ilmenite and perovskite, and gradually becomes more like perovskite until the core boundary is reached.

Venus is similar to Earth in size and density, and so probably also in bulk composition, but it does not have a significant magnetic field. Earth's magnetic field is produced by what is known as the core dynamo, consisting of an electrically conducting liquid, the nickel-iron outer core that rotates and is convecting. Venus is expected to have an electrically conductive core of similar composition, and although its rotation period is very long (243.7 Earth days), simulations show that this is adequate to produce a dynamo. This implies that Venus lacks convection in its outer core. Convection occurs when there is a large difference in temperature between the inner and outer part of the core, but since Venus has no plate tectonics to let off heat from the mantle, it is possible that outer core convection is being suppressed by a warm mantle. It's also possible that Venus may lack a solid inner core for the same reason, if the core is either too hot or is not under enough pressure to allow molten nickel-iron to freeze there.

Lava flows and channels

Lava originating from Ammavaru caldera (300 km outside the image) overflowed the ridge left of center and pooled to its right.

 

An anastomosing 2-km-wide lava channel in Sedna Planitia

Lava flows on Venus are often much larger than Earth's, up to several hundred kilometers long and tens of kilometers wide. It is still unknown why these lava fields or lobate flows reach such sizes, but it is suggested that they are the result of very large eruptions of basaltic, low-viscosity lava spreading out to form wide, flat plains.

On Earth, there are two known types of basaltic lava: ʻaʻa and pāhoehoe. ʻAʻa lava presents a rough texture in the shape of broken blocks (clinkers). Pāhoehoe lava is recognized by its pillowy or ropy appearance. Rough surfaces appear bright in radar images, which can be used to determine the differences between ʻaʻa and pāhoehoe lavas. These variations can also reflect differences in lava age and preservation. Channels and lava tubes (channels that have cooled down and over which a dome has formed) are very common on Venus. Two planetary astronomers from the University of Wollongong in Australia, Dr Graeme Melville and Prof. Bill Zealey, researched these lava tubes, using data supplied by NASA, over a number of years and concluded that they were widespread and up to ten times the size of those on the Earth. Melville and Zealey said that the gigantic size of the Venusian lava tubes (tens of meters wide and hundreds of kilometers long) may be explained by the very fluid lava flows together with the high temperatures on Venus, allowing the lava to cool slowly.

For the most part, lava flow fields are associated with volcanoes. The central volcanoes are surrounded by extensive flows that form the core of the volcano. They are also related to fissure craters, coronae, dense clusters of volcanic domes, cones, wells and channels.

Thanks to Magellan, more than 200 channels and valley complexes have been identified. The channels were classified as simple, complex, or compound. Simple channels are characterized by a single, long main channel. This category includes rills similar to those found on the Moon, and a new type, called canali, consisting of long, distinct channels which maintain their width throughout their entire course. The longest such channel identified (Baltis Vallis) has a length of more than 6,800 kilometres (4,200 mi), about one-sixth of the circumference of the planet.

Complex channels include anastomosed networks, in addition to distribution networks. This type of channel has been observed in association with several impact craters and important lava floods related to major lava flow fields. Compound channels are made of both simple and complex segments. The largest of these channels shows an anastomosed web and modified hills similar to those present on Mars.

Although the shape of these channels is highly suggestive of fluid erosion, there is no evidence that they were formed by water. In fact, there is no evidence of water anywhere on Venus in the last 600 million years. While the most popular theory for the channels' formation is that they are the result of thermal erosion by lava, there are other hypotheses, including that they were formed by heated fluids formed and ejected during impacts.

Surface processes

A map of Venus compiled from data recorded by NASA's Pioneer Venus Orbiter spacecraft beginning in 1978

Wind

Liquid water and ice are nonexistent on Venus, and thus the only agent of physical erosion to be found (apart from thermal erosion by lava flows) is wind. Wind tunnel experiments have shown that the density of the atmosphere allows the transport of sediments with even a small breeze. Therefore, the seeming rarity of eolian land forms must have some other cause. This implies that transportable sand-size particles are relatively scarce on the planet; which would be a result of very slow rates of mechanical erosion. The process that is most important for the production of sediment on Venus may be crater-forming impact events, which is bolstered by the seeming association between impact craters and downwind eolian land forms.

This process is manifest in the ejecta of impact craters expelled onto the surface of Venus. The material ejected during a meteorite impact is lifted to the atmosphere, where winds transport the material toward the west. As the material is deposited on the surface, it forms parabola-shaped patterns. This type of deposit can be established on top of various geologic features or lava flows. Therefore, these deposits are the youngest structures on the planet. Images from Magellan reveal the existence of more than 60 of these parabola-shaped deposits that are associated with crater impacts.

The ejection material, transported by the wind, is responsible for the process of renovation of the surface at speeds, according to the measurements of the Venera soundings, of approximately one metre per second. Given the density of the lower Venusian atmosphere, the winds are more than sufficient to provoke the erosion of the surface and the transportation of fine-grained material. In the regions covered by ejection deposits one may find wind lines, dunes, and yardangs. The wind lines are formed when the wind blows ejection material and volcanic ash, depositing it on top of topographic obstacles such as domes. As a consequence, the leeward sides of domes are exposed to the impact of small grains that remove the surface cap. Such processes expose the material beneath, which has a different roughness, and thus different characteristics under radar, compared to formed sediment.

The dunes are formed by the depositing of particulates that are the size of grains of sand and have wavy shapes. Yardangs are formed when the wind-transported material carves the fragile deposits and produces deep furrows.

The line-shaped patterns of wind associated with impact craters follow a trajectory in the direction of the equator. This tendency suggests the presence of a system of circulation of Hadley cells between medium latitudes and the equator. Magellan radar data confirm the existence of strong winds that blow toward the east in the upper surface of Venus, and meridional winds on the surface.

Chemical erosion

Chemical and mechanical erosion of the old lava flows is caused by reactions of the surface with the atmosphere in the presence of carbon dioxide and sulfur dioxide (see carbonate–silicate cycle for details). These two gases are the planet's first and third most abundant gases, respectively; the second most abundant gas is inert nitrogen. The reactions probably include the deterioration of silicates by carbon dioxide to produce carbonates and quartz, as well as the deterioration of silicates by sulfur dioxide to produce anhydrate calcium sulfate and carbon dioxide.

Ancient liquid water

NASA's Goddard Institute for Space Studies and others have postulated that Venus may have had a shallow ocean in the past for up to 2 billion years, with as much water as Earth. Depending on the parameters used in their theoretical model, the last liquid water could have evaporated as recently as 715 million years ago. Currently, the only known water on Venus is in the form of a tiny amount of atmospheric vapor (20 ppm). Hydrogen, a component of water, is still being lost to space nowadays as detected by ESA's Venus Express spacecraft.

Scientology and religious groups

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The relationship between Scientology and religious groups is very complex. While Scientology claims that it is fully compatible with all existing major world religions and that it does not conflict with them or their religious practices, there are significant contradictions between Scientology and most religions, especially the major monotheistic religions. Members are not allowed to engage in other similar mental therapies or procedures, religious or otherwise. However, some ministers from other churches have adopted some Scientology secular programs.

Religious compatibility

Scientology's claim of religious compatibility to entry-level Scientologists is soon modified by the additional teaching that the various levels of spiritual process which can be reached through Scientology are more advanced than those attainable in other religions. The major monotheistic religions and Scientology share the claim of Universality of their belief system which precludes compatibility in the view of most scholars. Critics point out that, within Scientology, "spiritual abilities" tends to be synonymous with "mystical powers" rather than with "inner peace." Hubbard himself cautioned against the unwise or improper use of powers in his book History of Man.

In its application for tax-exempt status in the United States, the Church of Scientology International states:

Although there is no policy or Scriptural mandate expressly requiring Scientologists to renounce other religious beliefs or membership in other churches, as a practical matter Scientologists are expected to and do become fully devoted to Scientology to the exclusion of other faiths. As Scientologists, they are required to look only to Scientology Scriptures for the answers to the fundamental questions of their existence and to seek enlightenment only from Scientology.

The revealed beliefs in Scientology at higher levels become increasingly contradictory with the world's major religions. The concept of past lives in Scientology is at odds with Christianity and Islam. Beliefs concerning the origins and age of the Earth, the root of evil, and the nature of man make it impossible to uphold the beliefs of most other religions while also being a Scientologist. Hubbard claimed that Islam was the result of an extraterrestrial memory implant, called the Emanator, of which the Kaaba is supposedly an artifact. Mainstream religions, in his view, had failed to realize their objectives: "It is all very well to idealize poverty and associate wisdom with begging bowls, or virtue with low estate. However, those who have done this (Buddhists, Christians, Communists, and other fanatics) have dead ended or are dead ending."

The section of the Fishman Affidavit pertaining to Operating Thetan level VIII put forward that Hubbard said that Jesus was a pederast. The Church of Scientology has consistently held this section of the Fishman Affidavit to be a forgery.

Hubbard had a basic skepticism about religious claims, even about the existence of God. In July 1950, upon addressing a child's queries about the existence of angels, he clearly showed that he was talking about something that didn't exist. In March 1954, he talked about mysticism, spiritualism, and "guardian angels and priests and all this sort of thing as the requirement to inquire from nothingness for direction." When referring to God he mentions "taking orders from an indefinite nothingness." Dianetics does not mention God.

According to scholar Mikael Rothstein, just as Jesus is the sole object of religious devotion and source of salvation, and the church is seen as an "extension" of Jesus' divinity, "the entire fabric of Scientology is best understood as an expansion of the individual, L. Ron Hubbard, including the buildings currently emerge as physical manifestations of Scientological ideals and virtues."

Buddhism and Hinduism

The Church of Scientology has capitalized on the religion's similarity to Buddhism to win followers in historically Buddhist-influenced countries like Taiwan.

Hubbard discussed Buddhism in an early 1952 lecture in London, speaking about Buddhist reincarnation stories, about the Christian God and other religious topics. While theologian Marco Frenschkowski claims that Hubbard may have been experimenting with ways Scientology is similar to Buddhism, some scholars such as Frank K. Flinn and Stephen A. Kent interpret the Scientology founder's "reverence for Buddhism as a rather awkward response to external pressure." Hubbard clarified that Scientology is not a neo-Buddhist group. Scientology and Buddhism differ in that in Scientology there is no concept of Nirvana. According to religious scholar Aldo Natale Terrin, in Buddhism, adherents aim to the suppression of the mind which is in direct opposition to the Scientologist idea of "transparency to himself". Flinn called Scientology technological Buddhism, however, it can be differentiated from Buddhist asceticism as its aim is not the eradication of pain through the removal of desire or detaching oneself from the world. Furthermore, it has nothing in common with Buddhist prayer offerings; it is not contemplative, but action-oriented and practical.

Hubbard sometimes identified himself with Maitreya (Metteya in Pali), a prophesied Buddha of the future. This identification is made most strongly in his 1955–1956 poem Hymn of Asia, which begins with the line "Am I Metteyya?" and emphasizes certain traits of Hubbard that the editors of the publication said matched traits predicted by the "Metteya Legend," such as Metteya appearing in the West, having golden hair or red hair (Hubbard was red-haired), and appearing in a time of world peril, with the earliest of the predicted dates for his return being 2,500 years after Gautama Buddha, or roughly 1950. According to Kent, however, the traits which the editors say are predicted by the "Metteya Legend" either are not actually present in the Buddhist texts or in some cases are contradicted by the texts: instead of coming at a time of world peril, for instance, the predictions about Maitreya say he will be born to royalty whose domain is "mighty and prosperous, full of people, crowded and well fed," and rather than having hair "like flames," Kent says that the texts predict curly black hair for the Maitreya.

Author Richard Holloway writes that the underlying principle in Scientology is the ancient Hindu doctrine of reincarnation or samsara, but without nirvana. Scientologists believe in the immortality of souls that travel from one body to another in a span of a trillion years, without final salvation or damnation. "There is only the eternal return of life after life."

Hubbard has made direct references to the comparison between Scientology and eastern religions: "But are we indebted to Asia?… All of us have the same potentials, but it happens that the information which has been collected over the years is available in Asia. It has been not preserved in the Western world. Therefore, we look to such things as the Veda." Hubbard says in the Phoenix Lectures: "And what we have just talked about in terms of knowing the way to Knowingness, is very, very closely associated here with Buddha, or Lord Buddha, or Gautama Buddha, or the Blessed One, or the Enlightened one."

In a study that compares Scientology with Eastern religions, scholar Roy Wallis wrote that there are a lot of parallelisms between Hindu yoga and Scientology. In Hindu yoga, the yoga system would lead to a knowledge where the rebirth bring about a "non conditioned mode of being" and the aim of Samkhya-yoga would consist in the dissociation of purusha (immortal spirit) from prakrti (matter). Now, the same would be the aim of Scientology in seeking to dissociate the Thetan – equivalent to purusha (immortal, free, divine) – in the attempt to liberate the self from the MEST (matter, prakrti).

Christianity

Church of England

The Church of England complained in March 2003 to the Advertising Standards Authority about the Church's advertising poster promoting Narconon—the drug rehabilitation program based on the works of L. Ron Hubbard. The poster claimed "250,000 people salvaged from drugs." The Church of England Diocese of Birmingham challenged the claim. Upholding the complaint, the ASA considered that, "without clarification, readers were likely to interpret the claim '250,000 people salvaged from drugs' to mean that 250,000 people had stopped being dependent on street or prescription drugs because of Scientology. The Authority "accepted that more than 250,000 people had undertaken the Church's Drug Purification and Drug Rundown programs, which were designed to free people from the effects of taking drugs," but "the Authority understood that, within Scientology, the concept of 'drug use' referred to a variety of behaviors that ranged from heavy use of street drugs to occasional ingestion of alcohol or prescription medicines and exposure to chemical toxins."

The Diocese of Birmingham objected to Scientology using space in the community centre allotted for religious use. The Diocese pointed out that Scientology does not have religious status in the UK: "Scientology has rightly been refused recognition as a religion by the UK Charity Commissioners" in the words of a Diocese spokesman. The Diocese also stated that Scientology is "as much a religion as a dog is a vegetable."

Eastern Orthodox Church

Maximos Aghiorgoussis, the bishop of the Greek Orthodox Archdiocese of America in Pittsburgh, has stated that Scientology is not in fact a "church", but rather a gnostic or theosophical system of thought. He went on to say that there are at least six serious points of contention between the two groups, including:

• the pantheistic nature of Scientology,
• Scientology's contention that the individual is a noncorporeal, semi-divine "thetan," which runs contrary to the Greek Orthodox view that the individual is both body and soul and, while created in the image of God, not a god himself,
• Scientology's belief that the universe is the "result of a game of the thetans", rather than the account of the Genesis creation narrative,
• Scientology's belief that the thetan can be saved through the clearing of its engrams, which differs from the Christian view of salvation being only through Christ, and
• Scientology's view that death is "of no consequence and significance because death is repeated innumerable times", which runs contrary to the Christian view of a single physical incarnation.

He also states that "Scientology teaches that psychic powers, (evil) spirits, and out-of-body events can be used in order for the thetans to rediscover their true powers. Because of this, there have been parallels drawn between Scientology and occultism. He goes on to say that, in spite of Scientology's claims to enhance mental health, that many people have already been damaged by Dianetics. Calling upon what he describes as "unclean spirits", the inexperience of those who do auditing cause "hallucination, irrational behavior, severe disorientation, strange bodily sensations, physical and mental illness, unconsciousness, and suicide. Hubbard admitted most of the above hazards, 'although he maintained that they occurred only through misapplication of the technology of Scientology'". In May 2001, the Russian Orthodox Church criticized Scientologists, Jehovah's Witnesses, Unificationists, and Mormons as being dangerous "totalitarian sects."

Lutheran Church

The Lutheran Church in Germany has criticized Scientology's activities and doctrines, along with those of several other religious movements. According to the U.S. State Department's 2004 Country Reports on Human Rights Practices, "The Lutheran Church also characterizes The Church of Jesus Christ of Latter-day Saints (Mormons), the Jehovah's Witnesses, the Church of Christ, Christian Scientists, the New Apostolic Church, and the Johannische Church as 'sects,' but in less negative terms than it does Scientology."

Roman Catholic Church

The Roman Catholic Church has not made official doctrinal pronouncements specifically related to Scientology, however Cardinal Marc Ouellet stated "Scientology is something else. For me, this community is not a Church." Certain beliefs that are widely associated with Scientology, such as reincarnation, are specifically rejected by the Catholic Church as being incompatible with Catholic belief and practice. Scientology is also, according to a number of religious scholars, a form of gnosticism, which would make it hard to reconcile with Roman Catholicism and other denominations that regard gnosticism as a heresy.

New religious movement scholar Douglas E. Cowan compares the basic auditing session in Scientology to the Roman Catholic confessional. He writes, "the auditing session is about confession – the discovery, revelation, and absolution of critical life experiences." He differentiates the two, however, the confession is mediated by the physicality of the screen and auditing is mediated by the e-meter.

Nation of Islam

Scientology's relationship with the Nation of Islam (NOI) is related to its inclusivity of other denominations, according to scholar Donald A. Westbrook. This relationship developed since 2009, with 4000 members of the NOI receiving introductory training as auditors with the endorsement of NOI Leader Louis Farrakhan. The affiliation between NOI and the Church of Scientology began when Tony Muhammad, head of the NOI Western Region was introduced to Scientology by Alfreddie Johnson. Farrakhan then asked Johnson about "growing a relationship" between NOI and the church. Johnson made a presentation about Scientology to Farrakhan in Clearwater, which resulted in Farrakhan pledging to go Clear and OT and train NOI ministers in the practice of Dianetics.

In May 2011, the Nation of Islam (NOI) announced in an official newspaper that an estimated 700 NOI members have become certified Hubbard Dianetics Auditors, with more NOI members soon to be trained in Scientology techniques.

Farrakhan is known to encourage his congregation to read Dianetics and receive training for auditing. Eliza Gray comments on a comparison and contrast of the two religions, asserting that "at the core of both religions is a never-ending pursuit of a better self. In the case of Scientology, that best self is 'clear' of residual traumas buried in the subconscious. In the Nation [of Islam], that self is free of hang-ups of white culture that black people have internalized to their detriment." Farrakhan has taught his followers to seek truth wherever it is contained, despite the inherent contradiction of following Hubbard's teaching while he poses resistance to the "whites." He declares to his followers that L. Ron Hubbard has made "white people better than they are," describing Hubbard's Dianetics as a way for "whites to expunge themselves from 'devilish' qualities."

Farrakhan supports Hubbard's spiritual technology, including auditing, which he claims is a "vital tool" for the awakening of his people. Leah Nelson writes that Farrakhan "has been telling his followers to embrace Scientology in order to move closer to perfection in preparation for the end times." Farrakhan has commented on the complementary and supplementary role that Scientology has on NOI. He does not necessarily view Dianetics training as conversion into Scientology, rather, he views Hubbard's technologies as tools for "black empowerment and betterment which contribute to his particular theological vision for Muslims in America," as Donald A. Westbrook writes. Speculating on Farrakhan's enthusiasm for Scientology, Chip Berlet of the Southern Poverty Law Center, hypothesizes: "The possibility exists that Farrakhan sees his followers as not 'clear' enough to make contact with the Mothership."

Gerald Williams asserts that just like NOI, Scientology is a "very rationalized or modern religion." Jacob Michael King states that both religions are "engaged in reframing traditional spiritual ideas, and both employ scientific language in an attempt to "modernize" elements seen as outdated." Dianetic Auditing runs parallel with NOI's determination of the knowledge of self. "While self-knowledge in the NOI offers the believer an identity as part of a collective, auditing through 'locating areas of spiritual distress… and improving their condition' purports to free the individual to determine herself and to better author her own destiny," states Jacob King.

Chicago, Inglewood, Hollywood and Clearwater are the loci of NOI Dianetics training. The Church of Scientology Community Center in Inglewood also functions as a Sunday meeting place for NOI members. Scientologists have also worked with NOI-lead initiatives to reduce crime rates in the Los Angeles inner cites, using the Scientology-sponsored program The Way to Happiness.

One-drop rule

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/One-drop_rule 

 

The one-drop rule is a legal principle of racial classification that was prominent in the 20th-century United States. It asserted that any person with even one ancestor of black ancestry ("one drop" of "black blood") is considered black (Negro or colored in historical terms). It is an example of hypodescent, the automatic assignment of children of a mixed union between different socioeconomic or ethnic groups to the group with the lower status, regardless of proportion of ancestry in different groups.

This concept became codified into the law of some U.S. states in the early 20th century. It was associated with the principle of "invisible blackness" that developed after the long history of racial interaction in the South, which had included the hardening of slavery as a racial caste system and later segregation.

Antebellum conditions

Further information: Partus sequitur ventrem, Children of the plantation, Quadroon, and High yellow

See also: Casta

Before the American Civil War, free individuals of mixed race (free people of color) were considered legally white if they had less than either one-eighth or one-quarter African ancestry (depending on the state). Many mixed-race people were absorbed into the majority culture based simply on appearance, associations and carrying out community responsibilities. These and community acceptance were the more important factors if a person's racial status were questioned, not their documented ancestry. Because of the social mobility of antebellum society in frontier areas, many people did not have documentation about their ancestors anyway.

Based on late 20th-century DNA analysis and a preponderance of historical evidence, US president Thomas Jefferson is widely believed to have fathered the six mixed-race children with his slave Sally Hemings, who was herself three-quarters white and a paternal half-sister of his wife Martha Wayles Jefferson. Four of them survived to adulthood. Under Virginia law of the time, while their seven-eighths European ancestry would have made them legally white if they’d been free, being born to an enslaved mother made them automatically enslaved from birth. Jefferson allowed the two oldest to escape in 1822 (freeing them legally was a public action he elected to avoid because he would have had to gain permission from the state legislature); the two youngest he freed in his 1826 will. Three of the four entered white society as adults. Subsequently, their descendants identified as white.

Although racial segregation was adopted legally by southern states of the former Confederacy in the late 19th century, legislators resisted defining race by law as part of preventing interracial marriages. In 1895, in South Carolina during discussion, George D. Tillman said,

It is a scientific fact that there is not one full-blooded Caucasian on the floor of this convention. Every member has in him a certain mixture of... colored blood...It would be a cruel injustice and the source of endless litigation, of scandal, horror, feud, and bloodshed to undertake to annul or forbid marriage for a remote, perhaps obsolete trace of Negro blood. The doors would be open to scandal, malice, and greed.

The one-drop rule was not formally codified as law until the 20th century, from 1910 in Tennessee to 1930 as one of Virginia's "racial integrity laws", with similar laws in several other states in between.

Native Americans

Further information: Lineal descendant and Blood quantum laws

In the early colonial years, children born of one Indigenous and one non-Native parent usually had a white father and an Indigenous mother. This was largely due to the majority of the early colonists being male. As many Native American tribes had matrilineal kinship systems, they considered the children to be born to the mother's family and clan. If they were raised in the culture, they were considered members of the community, and therefore, fully Native American.

Prior to colonization, and still in traditional communities, the idea of determining belonging by degree of "blood" was, and is, unheard of. Native American tribes did not use blood quantum law until the U.S. government introduced the Indian Reorganization Act of 1934, instead determining tribal status on the basis of kinship, lineage and family ties. However, many land cession treaties, particularly during Indian removal in the 19th century, contained provisions for "mixed-blood" descendants of European and native ancestry to receive either parcels of land ceded in the treaty, or a share in a lump sum of money, with specifications as to the degree of tribal ancestry required to qualify. Though these did not typically apply a one-drop rule, determining the ancestry of individual claimants was not straightforward, and the process was often rife with fraud.

Among patrilineal tribes, such as the Omaha, historically a child born to an Omaha mother and a white father could belong officially to the Omaha tribe only if the child were formally adopted into it by a male citizen. In contemporary practice, tribal laws around citizenship and parentage can vary widely between nations.

Between 1904 and 1919, tribal members with any amount of African ancestry were disenrolled from the Chitimacha tribe of Louisiana, and their descendants have since then been denied tribal membership.

20th century and contemporary times

In 20th-century America, the concept of the one-drop rule has been primarily applied by white Americans to those of sub-Saharan black African ancestry, when some whites were trying to maintain some degree of overt or covert white supremacy. The poet Langston Hughes wrote in his 1940 memoir:

You see, unfortunately, I am not black. There are lots of different kinds of blood in our family. But here in the United States, the word 'Negro' is used to mean anyone who has any Negro blood at all in his veins. In Africa, the word is more pure. It means all Negro, therefore black. I am brown.

This rule meant many mixed-race people, of diverse ancestry, were simply seen as African-American, and their more diverse ancestors forgotten and erased, making it difficult to accurately trace ancestry in the present day.

Many descendants of those who were enslaved and trafficked by Europeans and Americans have assumed they have Native American ancestry. Henry Louis Gates Jr.'s 2006 PBS documentary on the genetic makeup of African Americans, African American Lives, focused on these stories of Native American heritage in African-American communities. DNA test results showed, after African, primarily European ancestors for all but two of the celebrities interviewed. However, many critics point to the limitations of DNA testing for ancestry, especially for minority populations.

During World War II, Colonel Karl Bendetsen stated that anyone with "one drop of Japanese blood" was liable for forced internment in camps.

Today there are no enforceable laws in the U.S. in which the one-drop rule is applicable. Sociologically, however, the concept in recent years has become less acceptable within the Black community. Black people now consider mixed persons biracial, and do not automatically categorize them as Black. Research has found that in white society, it is still common to associate biracial children primarily with the individual's non-white ancestry.

Legislation and practice

Both before and after the American Civil War, many people of mixed ancestry who "looked white" and were of mostly white ancestry were legally absorbed into the white majority. State laws established differing standards. For instance, an 1822 Virginia law stated that to be defined as mulatto (that is, multi-racial), a person had to have at least one-quarter (equivalent to one grandparent) African ancestry. Social acceptance and identity were historically the keys to racial identity. Virginia's one-fourth standard remained in place until 1910, when the standard was changed to one sixteenth. In 1930, even the one sixteenth standard was abandoned in favor of a more stringent standard. The act defined a person as legally "colored" (black) for classification and legal purposes if the individual had any African ancestry.

Although the Virginia legislature increased restrictions on free blacks following the Nat Turner Rebellion of 1831, it refrained from establishing a one-drop rule. When a proposal was made by Travis H. Eppes and debated in 1853, representatives realized that such a rule could adversely affect whites, as they were aware of generations of interracial relationships. During the debate, a person wrote to the Charlottesville newspaper:

[If a one-drop rule were adopted], I doubt not, if many who are reputed to be white, and are in fact so, do not in a very short time find themselves instead of being elevated, reduced by the judgment of a court of competent jurisdiction, to the level of a free negro.

The state legislators agreed. No such law was passed until 1924, apparently assisted by the fading recollection of such mixed familial histories. In the 21st century, such interracial family histories are being revealed as individuals undergo DNA genetic analysis.

The Melungeons are a group of multiracial families of mostly European and African ancestry whose ancestors were free in colonial Virginia. They migrated to the frontier in Kentucky and Tennessee. Their descendants have been documented over the decades as having tended to marry persons classified as "white". Their descendants became assimilated into the majority culture from the 19th to the 20th centuries.

Pursuant to Reconstruction later in the 19th century, southern states acted to impose racial segregation by law and restrict the liberties of blacks, specifically passing laws to exclude them from politics and voting. From 1890 to 1908, all of the former Confederate states passed such laws, and most preserved disfranchisement until after passage of federal civil rights laws in the 1960s. At the South Carolina constitutional convention in 1895, an anti-miscegenation law and changes that would disfranchise blacks were proposed. Delegates debated a proposal for a one-drop rule to include in these laws. George D. Tillman said the following in opposition:

If the law is made as it now stands respectable families in Aiken, Barnwell, Colleton, and Orangeburg will be denied the right to intermarry among people with whom they are now associated and identified. At least one hundred families would be affected to my knowledge. They have sent good soldiers to the Confederate Army, and are now landowners and taxpayers. Those men served creditably, and it would be unjust and disgraceful to embarrass them in this way. It is a scientific fact that there is not one full-blooded Caucasian on the floor of this convention. Every member has in him a certain mixture of ... colored blood. The pure-blooded white has needed and received a certain infusion of darker blood to give him readiness and purpose. It would be a cruel injustice and the source of endless litigation, of scandal, horror, feud, and bloodshed to undertake to annul or forbid marriage for a remote, perhaps obsolete trace of Negro blood. The doors would be open to scandal, malice, and greed; to statements on the witness stand that the father or grandfather or grandmother had said that A or B had Negro blood in their veins. Any man who is half a man would be ready to blow up half the world with dynamite to prevent or avenge attacks upon the honor of his mother in the legitimacy or purity of the blood of his father.

In 1865, Florida passed an act that both outlawed miscegenation and defined the amount of Black ancestry needed to be legally defined as a "person of color". The act stated that "every person who shall have one-eighth or more of negro blood shall be deemed and held to be a person of color." (This was the equivalent of one great-grandparent.) Additionally, the act outlawed fornication, as well as the intermarrying of white females with men of color. However, the act permitted the continuation of marriages between white persons and persons of color that were established before the law was enacted.

Strangely enough, the one-drop rule was not made law until the early 20th century. This was decades after the Civil War, emancipation, and the Reconstruction era. It followed restoration of white supremacy in the South and the passage of Jim Crow racial segregation laws. In the 20th century, it was also associated with the rise of eugenics and ideas of racial purity. From the late 1870s on, white Democrats regained political power in the former Confederate states and passed racial segregation laws controlling public facilities, and laws and constitutions from 1890 to 1910 to achieve disfranchisement of most blacks. Many poor whites were also disfranchised in these years, by changes to voter registration rules that worked against them, such as literacy tests, longer residency requirements and poll taxes.

The first challenges to such state laws were overruled by Supreme Court decisions which upheld state constitutions that effectively disfranchised many. White Democratic-dominated legislatures proceeded with passing Jim Crow laws that instituted racial segregation in public places and accommodations, and passed other restrictive voting legislation. In Plessy v. Ferguson, the Supreme Court allowed racial segregation of public facilities, under the "separate but equal" doctrine.

Jim Crow laws reached their greatest influence during the decades from 1910 to 1930. Among them were hypodescent laws, defining as black anyone with any black ancestry, or with a very small portion of black ancestry. Tennessee adopted such a "one-drop" statute in 1910, and Louisiana soon followed. Then Texas and Arkansas in 1911, Mississippi in 1917, North Carolina in 1923, Alabama and Georgia in 1927, and Virginia in 1930. During this same period, Florida, Indiana, Kentucky, Maryland, Missouri, Nebraska, North Dakota, and Utah retained their old "blood fraction" statutes de jure, but amended these fractions (one-sixteenth, one-thirty-second) to be equivalent to one-drop de facto.

Before 1930, individuals of visible mixed European and African ancestry were usually classed as mulatto, or sometimes as black and sometimes as white, depending on appearance. Previously, most states had limited trying to define ancestry before "the fourth degree" (great-great-grandparents). But, in 1930, due to lobbying by southern legislators, the Census Bureau stopped using the classification of mulatto. Documentation of the long social recognition of mixed-race people was lost, and they were classified only as black or white.

The binary world of the one-drop rule disregarded the self-identification both of people of mostly European ancestry who grew up in white communities, and of people who were of mixed race and identified as American Indian. In addition, Walter Plecker, Registrar of Statistics, ordered application of the 1924 Virginia law in such a way that vital records were changed or destroyed, family members were split on opposite sides of the color line, and there were losses of the documented continuity of people who identified as American Indian, as all people in Virginia had to be classified as white or black. Over the centuries, many Indian tribes in Virginia had absorbed people of other ethnicities through marriage or adoption, but maintained their cultures. Suspecting blacks of trying to "pass" as Indians, Plecker ordered records changed to classify people only as black or white, and ordered offices to reclassify certain family surnames from Indian to black.

Since the late 20th century, Virginia has officially recognized eight American Indian tribes and their members; the tribes are trying to gain federal recognition. They have had difficulty because decades of birth, marriage, and death records were misclassified under Plecker's application of the law. No one was classified as Indian, although many individuals and families identified that way and were preserving their cultures.

In the case of mixed-race American Indian and European descendants, the one-drop rule in Virginia was extended only so far as those with more than one-sixteenth Indian blood. This was due to what was known as the "Pocahontas exception". Since many influential First Families of Virginia (FFV) claimed descent from the American Indian Pocahontas and her husband John Rolfe of the colonial era, the Virginia General Assembly declared that an individual could be considered white if having no more than one-sixteenth Indian "blood" (the equivalent of one great-great-grandparent).

The eugenist Madison Grant of New York wrote in his book, The Passing of the Great Race (1916): "The cross between a white man and an Indian is an Indian; the cross between a white man and a Negro is a Negro; the cross between a white man and a Hindu is a Hindu; and the cross between any of the three European races and a Jew is a Jew." As noted above, Native American tribes which had patrilineal descent and inheritance, such as the Omaha, classified children of white men and Native American women as white.

Plecker case

Main article: Walter Plecker

Through the 1940s, Walter Plecker of Virginia and Naomi Drake of Louisiana had an outsized influence. As the Registrar of Statistics, Plecker insisted on labeling mixed-race families of European-African ancestry as black. In 1924, Plecker wrote, "Two races as materially divergent as the White and Negro, in morals, mental powers, and cultural fitness, cannot live in close contact without injury to the higher." In the 1930s and 1940s, Plecker directed offices under his authority to change vital records and reclassify certain families as black (or colored) (without notifying them) after Virginia established a binary system under its Racial Integrity Act of 1924. He also classified people as black who had formerly self-identified as Indian. When the United States Supreme Court struck down Virginia's law prohibiting inter-racial marriage in Loving v. Virginia (1967), it also declared Plecker's Virginia Racial Integrity Act and the one-drop rule unconstitutional.

Many people in the U.S., among various ethnic groups, continue to have their own concepts related to the one-drop idea. They may still consider those multiracial individuals with any African ancestry to be black, or at least non-white (if the person has other minority ancestry), unless the person explicitly identifies as white. On the other hand, the Black Power movement and some leaders within the black community also claimed as black those persons with any visible African ancestry, in order to extend their political base and regardless of how those people self-identified.

Other countries of the Americas

Main article: Race and ethnicity in Latin America

 

Rice and Powell (on the left) are considered black in the US. Bush and Rumsfeld (on the right) are considered white.

Among the colonial slave societies, the United States was nearly unique in developing the one-drop rule; it derived both from the Southern slave culture (shared by other societies) and the aftermath of the American Civil War, emancipation of slaves, and Reconstruction. In the late 19th century, Southern whites regained political power and restored white supremacy, passing Jim Crow laws and establishing racial segregation by law. In the 20th century, during the Black Power movement, black race-based groups claimed all people of any African ancestry as black in a reverse way, to establish political power.

In colonial Spanish America, many soldiers and explorers took indigenous women as wives. Native-born Spanish women were always a minority. The colonists developed an elaborate classification and caste system that identified the mixed-race descendants of blacks, Amerindians, and whites by different names, related to appearance and known ancestry. Racial caste not only depended on ancestry or skin color, but also could be raised or lowered by the person's financial status or class.

Lena Horne was reportedly descended from the John C. Calhoun family, and both sides of her family were a mixture of African-American, Native American, and European American descent.

The same racial culture shock has come to hundreds of thousands of dark-skinned immigrants to the United States from Brazil, Colombia, Panama, and other Latin American nations. Although many are not considered black in their homelands, they have often been considered black in US society. According to The Washington Post, their refusal to accept the United States' definition of black has left many feeling attacked from all directions. At times, white and black Americans might discriminate against them for their lighter or darker skin tones; African Americans might believe that Afro-Latino immigrants are denying their blackness. At the same time, the immigrants think lighter-skinned Latinos dominate Spanish-language television and media. A majority of Latin Americans possess some African or American Indian ancestry. Many of these immigrants feel it is difficult enough to accept a new language and culture without the additional burden of having to transform from white to black. Yvette Modestin, a dark-skinned native of Panama who worked in Boston, said the situation was overwhelming: "There's not a day that I don't have to explain myself."

Professor J.B. Bird has said that Latin America is not alone in rejecting the historical US notion that any visible African ancestry is enough to make one black:

In most countries of the Caribbean, Colin Powell would be described as a Creole, reflecting his mixed heritage. In Belize, he might further be described as a "High Creole", because of his extremely light complexion.

Brazil

A Redenção de Cam (Redemption of Ham), by Galician painter Modesto Brocos, 1895, Museu Nacional de Belas Artes. The painting depicts a black grandmother, mulatta mother, white father and their quadroon child, hence three generations of hypergamy through racial whitening.

People in many other countries have tended to treat race less rigidly, both in their self-identification and how they regard others. Just as a person with physically recognizable African ancestry can claim to be black in the United States, someone with recognizable Caucasian ancestry may be considered white in Brazil, even if mixed race.

In December 2002, The Washington Post ran a story on the one-drop rule and differences in Latin American practices. In the reporter's opinion:

Someone with Sidney Poitier's deep chocolate complexion would be considered white if his hair were straight and he made a living in a profession. That might not seem so odd, Brazilians say, when you consider that the fair-complexioned actresses Rashida Jones of the television show "Boston Public" and Lena Horne are identified as black in the United States.

According to Jose Neinstein, a native white Brazilian and executive director of the Brazilian-American Cultural Institute in Washington, in the United States, "If you are not quite white, then you are black." However, in Brazil, "If you are not quite black, then you are white." Neinstein recalls talking with a man of Poitier's complexion when in Brazil: "We were discussing ethnicity, and I asked him, 'What do you think about this from your perspective as a black man?' He turned his head to me and said, 'I'm not black,' ... It simply paralyzed me. I couldn't ask another question."

Puerto Rico

During the Spanish colonial period, Puerto Rico had laws such as the Regla del Sacar or Gracias al Sacar, by which a person of black ancestry could be considered legally white so long as the individual could prove that at least one person per generation in the last four generations had also been legally white. Thus persons of some black ancestry with known white lineage were classified as white, the opposite of the "one-drop rule" in the United States.

Racial mixtures of blacks and whites in modern America

Given the intense interest in ethnicity, genetic genealogists and other scientists have studied population groups. Henry Louis Gates Jr. publicized such genetic studies on his two series African American Lives, shown on PBS, in which the ancestry of prominent figures was explored. His experts discussed the results of autosomal DNA tests, in contrast to direct-line testing, which survey all the DNA that has been inherited from the parents of an individual. Autosomal tests focus on SNPs.

The specialists on Gates' program summarized the make-up of the United States population by the following:

• 58 percent of African Americans have at least 12.5% European ancestry (equivalent of one great-grandparent);
• 19.6 percent of African Americans have at least 25% European ancestry (equivalent of one grandparent);
• 1 percent of African Americans have at least 50% European ancestry (equivalent of one parent) (Gates is one of these, he discovered, having a total of 51% European ancestry among various distant ancestors); and
• 5 percent of African Americans have at least 12.5% Native American ancestry (equivalent to one great-grandparent).

In 2002, Mark D. Shriver, a molecular anthropologist at Penn State University, published results of a study regarding the racial admixture of Americans who identified as white or black: Shriver surveyed a 3,000-person sample from 25 locations in the United States and tested subjects for autosomal genetic make-up:

• Of those persons who identified as white:
  • Individuals had an average 0.7% black ancestry, which is the equivalent of having 1 black and 127 white ancestors among one's 128 5×great-grandparents.
  • Shriver estimates that 70% of white Americans have no African ancestors (in part because a high proportion of current whites are descended from more recent immigrants from Europe of the late 19th and early 20th centuries, rather than those early migrants to the colonies, who in some areas lived and worked closely with Africans, free, indentured or slave, and formed relations with them).
  • Among the 30% of identified whites who have African ancestry, Shriver estimates their black racial admixture is 2.3%; the equivalent of having had three black ancestors among their 128 5×great-grandparents.
• Among those who identified as black:
  • The average proportion of white ancestry was 18%, the equivalent of having 22 white ancestors among their 128 5×great-grandparents.
  • About 10% have more than 50% white ancestry.

Black people in the United States are more racially mixed than white people, reflecting historical experience here, including the close living and working conditions among the small populations of the early colonies, when indentured servants, both black and white, and slaves, married or formed unions. Mixed-race children of white mothers were born free, and many families of free people of color were started in those years. 80 percent of the free African-American families in the Upper South in the censuses of 1790 to 1810 can be traced as descendants of unions between white women and African men in colonial Virginia, not of slave women and white men. In the early colony, conditions were loose among the working class, who lived and worked closely together. After the American Revolutionary War, their free mixed-race descendants migrated to the frontiers of nearby states along with other primarily European Virginia pioneers. The admixture also reflects later conditions under slavery, when white planters or their sons, or overseers, frequently raped African women. There were also freely chosen relationships among individuals of different or mixed races.

Shriver's 2002 survey found different current admixture rates by region, reflecting historic patterns of settlement and change, both in terms of populations who migrated and their descendants' unions. For example, he found that the black populations with the highest percentage of white ancestry lived in California and Seattle, Washington. These were both majority-white destinations during the Great Migration of 1940–1970 of African Americans from the Deep South of Louisiana, Texas and Mississippi. Blacks sampled in those two locations had more than 25% white European ancestry on average.

As noted by Troy Duster, direct-line testing of the Y-chromosome and mtDNA (mitochondrial DNA) fails to pick up the heritage of many other ancestors. DNA testing has limitations and should not be depended on by individuals to answer all questions about heritage. Duster said that neither Shriver's research nor Gates' PBS program adequately acknowledged the limitations of genetic testing.

Similarly, the Indigenous Peoples Council on Biocolonialism (IPCB) notes that: "Native American markers" are not found solely among Native Americans. While they occur more frequently among Native Americans, they are also found in people in other parts of the world. Genetic testing has shown three major waves of ancient migration from Asia among Native Americans but cannot distinguish further among most of the various tribes in the Americas. Some critics of testing believe that more markers will be identified as more Native Americans of various tribes are tested, as they believe that the early epidemics due to smallpox and other diseases may have altered genetic representation.

Much effort has been made to discover the ways in which the one-drop rule continues to be socially perpetuated today. For example, in her interview of black/white adults in the South, Nikki Khanna uncovers that one way the one-drop rule is perpetuated is through the mechanism of reflected appraisal. Most respondents identified as black, explaining that this is because both black and white people see them as black as well.

Allusions

Charles W. Chesnutt, who was of mixed race and grew up in the North, wrote stories and novels about the issues of mixed-race people in southern society in the aftermath of the Civil War.

The one-drop rule and its consequences have been the subject of numerous works of popular culture. The American musical Show Boat (1927) opens in 1887 on a Mississippi River boat, after the Reconstruction era and imposition of racial segregation and Jim Crow in the South. Steve, a white man married to a mixed-race woman who passes as white, is pursued by a Southern sheriff. He intends to arrest Steve and charge him with miscegenation for being married to a woman of partly black ancestry. Steve pricks his wife's finger and swallows some of her blood. When the sheriff arrives, Steve asks him whether he would consider a man to be white if he had "negro blood" in him. The sheriff replies that "one drop of Negro blood makes you a Negro in these parts". Steve tells the sheriff that he has "more than a drop of negro blood in me". After being assured by others that Steve is telling the truth, the sheriff leaves without arresting Steve.