Argument from free will

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https://en.wikipedia.org/wiki/Argument_from_free_will 

The argument from free will, also called the paradox of free will or theological fatalism, contends that omniscience and free will are incompatible and that any conception of God that incorporates both properties is therefore inconceivable. See the various controversies over claims of God's omniscience, in particular the critical notion of foreknowledge. These arguments are deeply concerned with the implications of predestination.

Omniscience and free will

If God made the game, its rules, and the players, then how can any player be free?

Some arguments against the existence of God focus on the supposed incoherence of humankind possessing free will and God's omniscience. These arguments are deeply concerned with the implications of predestination.

Noted Jewish philosopher Moses Maimonides described the conflict between divine omnipotence and his creation's person's free will, in traditional terms of good and evil actions, as follows:

… "Does God know or does He not know that a certain individual will be good or bad? If thou sayest 'He knows', then it necessarily follows that the man is compelled to act as God knew beforehand how he would act, otherwise, God's knowledge would be imperfect.…"

A "standard Anglican" theologian gave a similar description of Christian revelation:

… Scripture hold before us two great counter-truths – first, God's absolute sovereignty (cp Rome. 9, 20ff.), and secondly, man's responsibility. Our intellects cannot reconcile them.

A logical formulation of this argument might go as follows:

1. God knows choice "C" that a human would claim to "make freely".
2. It is now necessary that C.
3. If it is now necessary that C, then C cannot be otherwise (this is the definition of “necessary”). That is, there are no actual "possibilities" due to predestination.
4. If you cannot do otherwise when you act, you do not act freely (Principle of Alternate Possibilities)
5. Therefore, when you do an act, you will not do it freely.

Norman Swartz, however, contends that the above arguments commit the modal fallacy. In particular, he asserts that these arguments assume that if C is true, it becomes necessary for C to be true, which is incorrect as C is contingent (see modal logic). Otherwise, one can argue that the future is set already regardless of his actions.

Other means of reconciling God's omniscience with human free will have been proposed. Some have attempted to redefine or reconceptualize free will:

• God can know in advance what I will do, because free will is to be understood only as freedom from coercion, and anything further is an illusion. This is the move made by compatibilistic philosophies.
• The sovereignty (autonomy) of God, existing within a free agent, provides strong inner compulsions toward a course of action (calling), and the power of choice (election). The actions of a human are thus determined by a human acting on relatively strong or weak urges (both from God and the environment around them) and their own relative power to choose.

A proposition first offered by Boethius and later by Thomas Aquinas and C. S. Lewis, suggests that God's perception of time is different, and that this is relevant to our understanding of our own free will. In his book Mere Christianity, Lewis argues that God is actually outside time and therefore does not "foresee" events, but rather simply observes them all at once. He explains:

But suppose God is outside and above the Time-line. In that case, what we call "tomorrow" is visible to Him in just the same way as what we call "today". All the days are "Now" for Him. He does not remember you doing things yesterday, He simply sees you doing them: because, though you have lost yesterday, He has not. He does not "foresee" you doing things tomorrow, He simply sees you doing them: because, though tomorrow is not yet there for you, it is for Him. You never supposed that your actions at this moment were any less free because God knows what you are doing. Well, He knows your tomorrow's actions in just the same way – because He is already in tomorrow and can simply watch you. In a sense, He does not know your action till you have done it: but then the moment at which you have done it is already "Now" for Him.

A common objection is to argue that Molinism, or the belief that God can know counterfactually the actions of his creations, is true. This has been used as an argument by Alvin Plantinga and William Lane Craig, amongst others.

Free will argument for the nonexistence of God

Dan Barker suggests that this can lead to a "Free will Argument for the Nonexistence of God" on the grounds that God's omniscience is incompatible with God having free will and that if God does not have free will, God is not a personal being.

Theists generally agree that God is a personal being and that God is omniscient, but there is some disagreement about whether "omniscient" means:

1. "knows everything that God chooses to know and that is logically possible to know"; or instead the slightly stronger:
2. "knows everything that is logically possible to know"

These two terms are known as inherent and total omniscience, respectively.

Nuclear clock

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Nuclear_clock 

Concept of a thorium-229 based nuclear optical clock.
Industry	scientific, satellite navigation, and data transfer
Application	time-keeping

A nuclear clock or nuclear optical clock is an atomic clock being developed that will use the energy of a nuclear isomeric transition as its reference frequency, instead of the atomic electron transition energy used by conventional atomic clocks. Such a clock is expected to be more accurate than the best current atomic clocks by a factor of about 10, with an achievable accuracy approaching the 10⁻¹⁹ level.

The only nuclear state suitable for the development of a nuclear clock using existing technology is thorium-229m, an isomer of thorium-229 and the lowest-energy nuclear isomer known. With an energy of 8.355733554021(8) eV, this corresponds to a frequency of 2020407384335±2 kHz, or wavelength of 148.382182883 nm, in the vacuum ultraviolet region, making it accessible to laser excitation.

Principle of operation

Atomic clocks are today's most accurate timekeeping devices. They operate by exploiting the fact that the gap between the energy levels of two bound electron states in an atom is constant across space and time. A bound electron can be excited with electromagnetic radiation precisely when the radiation's photon energy matches the energy of the transition. Via the Planck relation, that transition energy corresponds to a particular frequency. By irradiating an appropriately prepared collection of identical atoms and measuring the number of excitations induced, a light source's frequency can be tuned to maximize this response and therefore closely match the corresponding electron transition energy. The transition energy thus provides a standard of reference which can be used to calibrate such a source reliably.

Conventional atomic clocks use microwave (high-frequency radio wave) frequencies, but development of the laser has made it possible to generate very stable light frequencies, and the frequency comb makes it possible to count those oscillations (measured in hundreds of THz, meaning hundred of trillions of cycles per second) to extraordinarily high accuracy. A device which uses a laser in this way is known as an optical atomic clock.

One prominent example of an optical atomic clock is the ytterbium (Yb) lattice clock, where a particular electron transition in the ytterbium-171 isotope is used for laser stabilization. In this case, one second has elapsed after 518295836590863.63±0.1 oscillations of the laser light stabilized to the corresponding electron transition. Other examples for optical atomic clocks of the highest accuracy are the Yb-171 single-ion clock, the strontium(Sr)-87 optical lattice clock, and the aluminum(Al)-27 single-ion clock. The achieved accuracies of these clocks vary around 10⁻¹⁸, corresponding to about 1 second of inaccuracy in 30 billion years, significantly longer than the age of the universe.

A nuclear optical clock would use the same principle of operation, with the important difference that a nuclear transition instead of an atomic shell electron transition is used for laser stabilization. The expected advantage of a nuclear clock is that the atomic nucleus is smaller than the atomic shell by up to five orders of magnitude, with correspondingly smaller magnetic dipole and electric quadrupole moments, and is therefore significantly less affected by external magnetic and electric fields. Such external perturbations are the limiting factor for the achieved accuracies of electron-based atomic clocks. Due to this conceptual advantage, a nuclear optical clock is expected to achieve a time accuracy approaching 10⁻¹⁹, a ten-fold improvement over electron-based clocks.

Ionization

An excited atomic nucleus can shed its excess energy by two alternative paths:

• radiatively, by direct photon (gamma ray) emission, or
• by internal conversion, transferring the energy to a shell electron which is ejected from the atom.

For most nuclear isomers, the available energy is sufficient to eject any electron, and the inner-shell electrons are the most frequently ejected. In the special case of ^229m
Th, the energy is sufficient only to eject an outer electron (thorium's first ionization energy is 6.3 eV), and if the atom is already ionized, there is not enough energy to eject a second (thorium's second ionization energy is 11.5 eV).

The two decay paths have different half-lives. Neutral ^229m
Th decays almost exclusively by internal conversion, with a half-life of 7±1 μs. In thorium cations, internal conversion is energetically prohibited, and ^229m
Th⁺
is forced to take the slower path, decaying radiatively with a half-life of around half an hour.

Thus, in the typical case that the clock is designed to measure radiated photons, it is necessary to hold the thorium in an ionized state. This can be done in an ion trap, or by embedding it in an ionic crystal with a band gap greater than the transition energy. In this case, the atoms are not 100% ionized, and a small amount of internal conversion is possible (reducing the half-life to approximately 10 minutes), but the loss is tolerable.

Different nuclear clock concepts

Two different concepts for nuclear optical clocks have been discussed in the literature: trap-based nuclear clocks and solid-state nuclear clocks.

Trap-based nuclear clocks

For a trap-based nuclear clock either a single ²²⁹Th³⁺ ion is trapped in a Paul trap, known as the single-ion nuclear clock, or a chain of multiple ions is trapped, considered as the multiple-ion nuclear clock. Such clocks are expected to achieve the highest time accuracy, as the ions are to a large extent isolated from their environment. A multiple-ion nuclear clock could have a significant advantage over the single-ion nuclear clock in terms of stability performance.

Solid-state nuclear clocks

As the nucleus is largely unaffected by the atomic shell, it is also intriguing to embed many nuclei into a crystal lattice environment. This concept is known as the crystal-lattice nuclear clock. Due to the high density of embedded nuclei of up to 10¹⁸ per cm³, this concept would allow irradiating a huge number of nuclei in parallel, thereby drastically increasing the achievable signal-to-noise ratio, but at the cost of potentially higher external perturbations. It has also been proposed to irradiate a metallic ²²⁹Th surface and to probe the isomer's excitation in the internal conversion channel, which is known as the internal-conversion nuclear clock. Both types of solid-state nuclear clocks were shown to offer the potential for comparable performance.

Transition requirements

From the principle of operation of a nuclear optical clock, it is evident that direct laser excitation of a nuclear state is a central requirement for the development of such a clock. This is impossible for most nuclear transitions, as the typical energy range of nuclear transitions (keV to MeV) is orders of magnitude above the maximum energy which is accessible with significant intensity by today's narrow-bandwidth laser technology (a few eV). There are only two nuclear excited states known which possess a sufficiently low excitation energy (below 100 eV). These are

• ^229m
  Th, a metastable nuclear excited state of the isotope thorium-229 with an excitation energy of only about 8 eV, and
• ^235m1
  U, a metastable excited state of uranium-235 with an energy of 76.7 eV.

However, ^235m1
U has such an extraordinarily long radiative half-life (on the order of 10²² s, 20,000 times the age of the universe, and far longer than its internal conversion half-life of 26 minutes) that it is not practical to use for a clock. This leaves only ^229mTh with a realistic chance of direct nuclear laser excitation.

Further requirements for the development of a nuclear clock are that

• the lifetime of the nuclear excited state is relatively long, thereby leading to a resonance of narrow bandwidth (a high quality factor) and
• the ground-state nucleus is easily available and sufficiently long-lived to allow one to work with moderate quantities of the material.

Fortunately, with ^229m
Th⁺
having a radiative half-life (time to decay to ²²⁹
Th⁺
) of around 10³ s, and ²²⁹
Th having a half-life (time to decay to ²²⁵
Ra) of 7917±48 years, both conditions are fulfilled for ^229m
Th⁺
, making it an ideal candidate for the development of a nuclear clock.

History

History of nuclear clocks

As early as 1996 it was proposed by Eugene V. Tkalya to use the nuclear excitation as a "highly stable source of light for metrology".

With the development (around 2000) of the frequency comb for measuring optical frequencies exactly, a nuclear optical clock based on ^229m
Th was first proposed in 2003 by Ekkehard Peik and Christian Tamm, who developed an idea of Uwe Sterr. The paper contains both concepts, the single-ion nuclear clock, as well as the solid-state nuclear clock.

In their pioneering work, Peik and Tamm proposed to use individual laser-cooled ²²⁹
Th³⁺
ions in a Paul trap to perform nuclear laser spectroscopy. Here the 3+ charge state is advantageous, as it possesses a shell structure suitable for direct laser cooling. It was further proposed to excite an electronic shell state, to achieve 'good' quantum numbers of the total system of the shell plus nucleus that will lead to a reduction of the influence induced by external perturbing fields. A central idea is to probe the successful laser excitation of the nuclear state via the hyperfine-structure shift induced into the electronic shell due to the different nuclear spins of ground- and excited state. This method is known as the double-resonance method.

The expected performance of a single-ion nuclear clock was further investigated in 2012 by Corey Campbell et al. with the result that a systematic frequency uncertainty (accuracy) of the clock of 1.5×10⁻¹⁹ could be achieved, which would be by about an order of magnitude better than the accuracy achieved by the best optical atomic clocks today. The nuclear clock approach proposed by Campbell et al. slightly differs from the original one proposed by Peik and Tamm. Instead of exciting an electronic shell state in order to obtain the highest insensitivity against external perturbing fields, the nuclear clock proposed by Campbell et al. uses a stretched pair of nuclear hyperfine states in the electronic ground-state configuration, which appears to be advantageous in terms of the achievable quality factor and an improved suppression of the quadratic Zeeman shift.

In 2010, Eugene V. Tkalya showed that it was theoretically possible to use ^229m
Th as a lasing medium to generate an ultraviolet laser.

The solid-state nuclear clock approach was further developed in 2010 by W.G. Rellergert et al. with the result of an expected long-term accuracy of about 2×10⁻¹⁶. Although expected to be less accurate than the single-ion nuclear clock approach due to line-broadening effects and temperature shifts in the crystal lattice environment, this approach may have advantages in terms of compactness, robustness and power consumption. The expected stability performance was investigated by G. Kazakov et al. in 2012. In 2020, the development of an internal conversion nuclear clock was proposed.

Important steps on the road towards a nuclear clock include the successful direct laser cooling of ²²⁹
Th³⁺
ions in a Paul trap achieved in 2011, and a first detection of the isomer-induced hyperfine-structure shift, enabling the double-resonance method to probe a successful nuclear excitation in 2018.

History of ^229mTh

Main article: Isotopes of thorium § Thorium-229m

Since 1976, the ²²⁹Th nucleus has been known to possess a low energy excited state, whose excitation energy was originally shown to less than 100 eV, and then shown to be less than 10 eV in 1990.

This was, however, too broad an energy range to apply high-resolution spectroscopy techniques; the transition energy had to be narrowed down first. Initial efforts used the fact that, after the alpha decay of ²³³
U, the resultant ²²⁹
Th nucleus is in an excited state and promptly emits a gamma ray to decay to either the base state or the metastable state. Measuring the small difference in the gamma-ray energies emitted in these processes allows the metastable state energy to be found by subtraction. However, nuclear experiments are not capable of finely measuring the difference in frequency between two high gamma-ray energies, so other experiments were needed. Because of the natural radioactive decay of ²²⁹Th nuclei, a tightly concentrated laser frequency was required to excite enough nuclei in an experiment to outcompete the background radiation and give a more accurate measurement of the excitation energy. Because it was infeasible to scan the entire 100eV range, an estimate of the correct frequency was needed.

An early mis-step was the (incorrect) measurement of the energy value as 3.5±1.0 eV in 1994. This frequency of light is relatively easy to work with, so many direct detection experiments were attempted which had no hope of success because they were built of materials opaque to photons at the true, higher, energy. In particular:

• thorium oxide is transparent to 3.5 eV photons, but opaque at 8.3 eV,
• common optical lens and window materials such as fused quartz are opaque at energies above 8 eV,
• molecular oxygen (air) is opaque to photons above 6.2 eV; experiments must be conducted in a nitrogen or argon atmosphere, and
• the ionization energy of thorium is 6.3 eV so the nuclei will decay by internal conversion unless prevented (see § Ionization).

The energy value remained elusive until 2003, when the nuclear clock proposal triggered a multitude of experimental efforts to pin down the excited state's parameters like energy and half-life. The detection of light emitted in the direct decay of ^229m
Th would significantly help to determine its energy to higher precision, but all efforts to observe the light emitted in the decay of ^229m
Th were failing. The energy level was corrected to 7.6±0.5 eV in 2007 (slightly revised to 7.8±0.5 eV in 2009). Subsequent experiments continued to fail to observe any signal of light emitted in the direct decay, leading people to suspect the existence of a strong non-radiative decay channel. The detection of light emitted by the decay of ^229mTh was reported in 2012, and again in 2018, but the observed signals were the subject of controversy within the community.

A direct detection of electrons emitted by the isomer's internal conversion decay channel was achieved in 2016. This detection laid the foundation for the determination of the ^229mTh half-life in neutral, surface-bound atoms in 2017 and a first laser-spectroscopic characterization in 2018.

In 2019, the isomer's energy was measured via the detection of internal conversion electrons emitted in its direct ground-state decay to 8.28±0.17 eV. Also a first successful excitation of the 29 keV nuclear excited state of ²²⁹
Th via synchrotron radiation was reported, enabling a clock transition energy measurement of 8.30±0.92 eV. In 2020, an energy of 8.10±0.17 eV was obtained from precision gamma-ray spectroscopy.

Finally, precise measurements were achieved in 2023 by unambiguous detection of the emitted photons (8.338(24) eV) and in April 2024 by two reports of excitation with a tunable laser at 8.355733(10) eV and 8.35574(3) eV. The light frequency is now known with sufficient accuracy to enable future construction of a prototype clock, and determine the transition's exact frequency and its stability.

Precision frequency measurements began immediately, with Jun Ye's laboratory at JILA making a direct comparison to a ⁸⁷
Sr optical atomic clock. Published in September 2024, the frequency was measured as 2020407384335±2 kHz, a relative uncertainty of 10⁻¹². This implies a wavelength of 148.3821828827(15) nm and an energy of 8.355733554021(8) eV. The work also resolved different nuclear quadrupole sublevels and measured the ratio of the ground and excited state nuclear quadrupole moment. Improvements will surely follow.

Applications

When operational, a nuclear optical clock is expected to be applicable in various fields. In addition to the capabilities of today's atomic clocks, such as satellite-based navigation or data transfer, its high precision will allow new applications inaccessible to other atomic clocks, such as relativistic geodesy, the search for topological dark matter, or the determination of time variations of fundamental constants.

A nuclear clock has the potential to be particularly sensitive to possible time variations of the fine-structure constant. The central idea is that the low energy is due to a fortuitous cancellation between strong nuclear and electromagnetic effects within the nucleus which are individually much stronger. Any variation the fine-structure constant would affect the electromagnetic half of this balance, resulting in a proportionally very large change in the total transition energy. A change of even one part in 10¹⁸ could be detected by comparison with a conventional atomic clock (whose frequency would also be altered, but not nearly as much), so this measurement would be extraordinarily sensitive to any potential variation of the constant. Recent measurements and analysis are consistent with enhancement factors on the order of 10⁴.

Family tree

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Family_tree

Example of a family tree. Reading left to right Lucas Grey is the father of three children, the grandfather of five grandchildren and the great-grandfather of three siblings Joseph, John and Laura Wetter.

Family tree showing the relationship of each person to the orange person, including cousins and gene share

A family tree, also called a genealogy or a pedigree chart, is a chart representing family relationships in a conventional tree structure. More detailed family trees, used in medicine and social work, are known as genograms.

Representations of family history

Three generations of ancestors (born from 1824 to 1916) placed on a Swedish kurbits tree

Genealogical data can be represented in several formats, for example, as a pedigree or ancestry chart. Family trees are often presented with the oldest generations at the top of the tree and the younger generations at the bottom. An ancestry chart, which is a tree showing the ancestors of an individual and not all members of a family, will more closely resemble a tree in shape, being wider at the top than at the bottom. In some ancestry charts, an individual appears on the left and his or her ancestors appear to the right. Conversely, a descendant chart, which depicts all the descendants of an individual, will be narrowest at the top. Beyond these formats, some family trees might include all members of a particular surname (e.g., male-line descendants). Yet another approach is to include all holders of a certain office, such as the Kings of Germany, which represents the reliance on marriage to link dynasties together.

The passage of time can also be included to illustrate ancestry and descent. A time scale is often used, expanding radially across the center, divided into decades. Children of the parent form branches around the center and their names are plotted in their birth year on the time scale. Spouses' names join children's names and nuclear families of parents and children branch off to grandchildren, and so on. Great-grandparents are often in the center to portray four or five generations, which reflect the natural growth pattern of a tree as seen from the top but sometimes there can be great-great-grandparents or more. In a descendant tree, living relatives are common on the outer branches and contemporary cousins appear adjacent to each other. Privacy should be considered when preparing a living family tree.

The image of the tree probably originated with that of the Tree of Jesse in medieval art, used to illustrate the Genealogy of Christ in terms of a prophecy of Isaiah (Isaiah 11:1). Possibly the first non-biblical use, and the first to show full family relationships rather than a purely patrilineal scheme, was that involving family trees of the classical gods in Boccaccio's Genealogia Deorum Gentilium ("On the Genealogy of the Gods of the Gentiles"), whose first version dates to 1360.

Common formats

In addition to familiar representations of family history and genealogy as a tree structure, there are other notable systems used to illustrate and document ancestry and descent.

Ahnentafel

Main article: Ahnentafel

An ahnentafel family tree displaying an ancestor chart of Sigmund Christoph, Graf von Zeil und Trauchburg

An Ahnentafel (German for "ancestor table") is a genealogical numbering system for listing a person's direct ancestors in a fixed sequence of ascent:

1. Subject (or proband)
2. Father
3. Mother
4. Paternal grandfather
5. Paternal grandmother
6. Maternal grandfather
7. Maternal grandmother

and so on, back through the generations. Apart from the subject or proband, who can be male or female, all even-numbered persons are male, and all odd-numbered persons are female. In this scheme, the number of any person's father is double the person's number, and a person's mother is double the person's number plus one. This system can also be displayed as a tree:

An ahnentafel family tree, showing three generations of the Kennedy family

							4. Paternal grandfather
				2. Father
							5. Paternal grandmother
	1 Subject (or proband)
							6. Maternal grandfather
				3. Mother
							7. Maternal grandmother

Fan chart

Screenshot of Gramps (v. 5.0.1) displaying a fan chart and the given name cloud gramplet on the bottom

A fan chart features a half circle chart with concentric rings: the subject is the inner circle, the second circle is divided in two (each side is one parent), the third circle is divided in four, and so forth. Fan charts depict paternal and maternal ancestors.

Graph theory

While family trees are depicted as trees, family relations do not in general form a tree in the strict sense used in graph theory, since distant relatives can mate. Therefore, a person can have a common ancestor on both their mother's and father's side. However, because a parent must be born before their child, an individual cannot be their own ancestor, and thus there are no loops. In this regard, ancestry forms a directed acyclic graph. Nevertheless, graphs depicting matrilineal descent (mother-daughter relationships) and patrilineal descent (father-son relationships) do form trees. Assuming no common ancestor, an ancestry chart is a perfect binary tree, as each person has exactly one mother and one father; these thus have a regular structure. A Descendant chart, on the other hand, does not, in general, have a regular structure, as a person can have any number of children or none at all.

Notable examples

Family trees are an age-old phenomenon. This example dates from the sixteenth century.

Family trees have been used to document family histories across time and cultures throughout the world.

Africa

In Africa, the ruling dynasty of Ethiopia claimed descent from King Solomon via the Queen of Sheba. Through this claim, the family traced their descent back to the House of David.

The genealogy of Ancient Egyptian ruling dynasties was recorded from the beginnings of the Pharaonic era c. 3000 BC to the end of the Ptolomaic Kingdom; although this is not a record of one continuously linked family lineage, and surviving records are incomplete.

Elsewhere in Africa, oral traditions of genealogical recording predominate. Members of the Keita dynasty of Mali, for example, have had their pedigrees sung by griots during annual ceremonies since the 14th century. Meanwhile, in Nigeria, many ruling clans—most notably those descended from Oduduwa—claim descent from the legendary King Kisra. Here too, pedigrees are recited by griots attached to the royal courts.

The Americas

In some pre-contact Native American civilizations, genealogical records of ruling and priestly families were kept, some of which extended over several centuries or longer.

Pre-Islamic Arabia

In pre-Islamic Arabia, the Arab tribes were often organized around extended family units, and tribal identity was key to understanding one's heritage and honor. Each tribe, or qabila, would trace its lineage back to a common ancestor. These genealogies were passed down orally, with poets, historians, and storytellers responsible for preserving these family histories. The Arabs were well known for their oral traditions and poetry, where family lineages were often preserved in elaborate genealogies. For example, many pre-Islamic poets like Imru' al-Qais referenced their tribal heritage and the great ancestors of their families in their poetry.

Islamic Era and Beyond

With the rise of Islam in the 7th century, genealogy took on even more significance, particularly for those having descent from the Prophet Muhammad. Sayyids (those who trace their lineage back to the Prophet) and Hashemites (the family of the Prophet's clan) have been highly regarded throughout history. The Prophet Muhammad's family tree is one of the most well-known genealogical records in the Arab world. The Islamic era also formalized the recording of genealogies, with Islamic scholars beginning to document and preserve family histories in written form. This was not only important for religious reasons but also for maintaining tribal alliances, political power, and historical records. The First Recorded Arab Genealogical Trees. The first known recorded genealogical trees for Arabs are largely from the early Islamic period, and these genealogies were meticulously recorded by historians, genealogists, and scholars.

The Genealogy of the Prophet Muhammad

One of the most famous early genealogical trees in the Arab world is that of Prophet Muhammad. His genealogy was carefully documented in various Islamic texts, and it traces his lineage to Ishmael, the son of Abraham. The family tree is crucial in establishing the Prophet's noble lineage. This line of descent is known as the Hashemite lineage, originating from Hashim, a forefather of the Prophet, and it remains one of the most revered lineages in the Arab world. The Book of Lineages (كتاب الأنساب, Kitab al-Ansab)The early Islamic genealogist Ibn Hajar al-Asqalani (1372–1449) compiled a monumental work called "Kitab al-Ansab", which documents the genealogies of various Arab tribes. His work was based on earlier genealogical sources and serves as a foundational resource for understanding Arab tribal and familial lineages. Ibn Khaldun and Genealogies: Another important historical figure, Ibn Khaldun (1332–1406), a famous historian and philosopher, included discussions on genealogy in his renowned work, Muqaddimah. In his writing, he explored the role of tribes and lineages in Arab society, and this work contributed to the study of genealogies as part of social and political structures. Early Arab Family Trees and Tribal Systems Tribal Clans: Ancient Arab society was deeply rooted in the concept of tribal affiliation. The family tree often extended across large tribal networks that governed the social and political dynamics of pre-Islamic Arabia. Families like the Quraysh tribe (to which the Prophet Muhammad belonged) and the Banu Hashim clan were particularly significant. In these tribes, each family, or bayt, would have its own genealogical history, and knowing one's ancestry was considered essential for social status, marriage eligibility, and political power. Recorded Genealogies for Prestige and Protection: Genealogies also served as a form of social security. By tracing one's family history back to notable ancestors, a family could bolster its claim to land, resources, or power. It also ensured that family members could protect themselves against challenges to their status or inheritance. The Role of Ilm al-Ansab (Genealogy Science)The science of genealogy (Ilm al-Ansab) became a recognized scholarly field within the Arab world. Scholars and experts in genealogy would specialize in documenting, analyzing, and preserving genealogical records for the Arab tribes. This process led to the creation of family trees that not only had historical value but also served as political tools, especially in contexts where tribal affiliation played a key role in gaining or maintaining power. While we can trace recorded family trees in the Arab world back to the early Islamic period, with prominent examples like the genealogy of the Prophet Muhammad and scholarly works by figures like Ibn Khaldun and Ibn Hajar al-Asqalani, the practice of preserving and documenting family lineages has ancient roots in Arab culture. Tribal identity and genealogical knowledge were integral to the social fabric of pre-Islamic Arabia and continue to play a significant role in modern Arab societies. The family tree, therefore, has always been a crucial part of Arab heritage, not just as a way of tracing descent but as a means of preserving cultural identity and social structure.

East Asia

There are extensive genealogies for the ruling dynasties of China, but these do not form a single, unified family tree. Additionally, it is unclear at which point(s) the most ancient historical figures named become mythological.

In Japan, the ancestry of the Imperial Family is traced back to the mythological origins of Japan. The connection to persons from the established historical record only begins in the mid-first millennium AD.

The longest family tree in the world is that of the Chinese philosopher and educator Confucius (551–479 BC), who is descended from King Tang (1675–1646 BC). The tree spans more than 80 generations from him and includes more than 2 million members. An international effort involving more than 450 branches around the world was started in 1998 to retrace and revise this family tree. A new edition of the Confucius genealogy was printed in September 2009 by the Confucius Genealogy Compilation Committee, to coincide with the 2560th anniversary of the birth of the Chinese thinker. This latest edition was expected to include some 1.3 million living members who are scattered around the world today.

Europe and West Asia

Before the Dark Ages, in the Greco-Roman world, some reliable pedigrees dated back perhaps at least as far as the first half of the first millennium BC; with claimed or mythological origins reaching back further. Roman clan and family lineages played an important part in the structure of their society and were the basis of their intricate system of personal names. However, there was a break in the continuity of record-keeping at the end of Classical Antiquity. Records of the lines of succession of the Popes and the Eastern Roman Emperors through this transitional period have survived, but these are not continuous genealogical histories of single families. Refer to descent from antiquity.

Many noble and aristocratic families of European and West Asian origin can reliably trace their ancestry back as far as the mid to late first millennium AD; some claiming undocumented descent from Classical Antiquity or mythological ancestors. In Europe, for example, the pedigree of Niall Noígíallach would be a contender for the longest, through Conn of the Hundred Battles (fl. 123 AD); in the legendary history of Ireland, he is further descended from Breogán, and ultimately from Adam, through the sons of Noah.

Another very old and extensive tree is that of the Lurie lineage—which includes Sigmund Freud and Martin Buber—and traces back to Lurie, a 13th-century rabbi in Brest-Litovsk, and from there to Rashi and purportedly back to the legendary King David, as documented by Neil Rosenstein in his book The Lurie Legacy.^[8] The 1999 edition of the Guinness Book of Records recorded the Lurie family in the "longest lineage" category as one of the oldest-known living families in the world today.

Family trees and representations of lineages are also important in religious traditions. The biblical genealogies of Jesus also claim descent from the House of David, covering a period of approximately 1000 years. In the Torah and Old Testament, genealogies are provided for many biblical persons, including a record of the descendants of Adam. Also according to the Torah, the Kohanim are descended from Aaron. Genetic testing performed at the Technion has shown that most modern Kohanim share common Y-chromosome origins, although there is no complete family tree of the Kohanim. In the Islamic world, claimed descent from Muhammad greatly enhanced the status of political and religious leaders; new dynasties often used claims of such descent to help establish their legitimacy.

Elsewhere

Elsewhere, in many human cultures, clan and tribal associations are based on claims of common ancestry, although detailed documentation of those origins is often very limited.

Global

Forms of family trees are also used in genetic genealogy. In 2022, scientists reported the largest detailed human genetic genealogy, that unifies human genomes from many sources for insights about human history, ancestry and evolution and demonstrates a novel computational method for estimating how human DNA is related via a series of 13 million linked trees along the genome, a tree-sequence, which has been described as the largest "human family tree".

Conservation status

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Conservation_status 

The conservation status of a group of organisms (for instance, a species) indicates whether the group still exists and how likely the group is to become extinct in the near future. Many factors are taken into account when assessing conservation status: not simply the number of individuals remaining, but the overall increase or decrease in the population over time, breeding success rates, and known threats. Various systems of conservation status are in use at international, multi-country, national and local levels, as well as for consumer use such as sustainable seafood advisory lists and certification. The two international systems are by the International Union for Conservation of Nature (IUCN) and The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES).

International systems

IUCN Red List of Threatened Species

The IUCN Red List of Threatened Species by the International Union for Conservation of Nature is the best known worldwide conservation status listing and ranking system. Species are classified by the IUCN Red List into nine groups set through criteria such as rate of decline, population size, area of geographic distribution, and degree of population and distribution fragmentation.

Also included are species that have gone extinct since 1500 CE. When discussing the IUCN Red List, the official term "threatened" is a grouping of three categories: critically endangered, endangered, and vulnerable.

• Extinct (EX) – There are no known living individuals
• Extinct in the wild (EW) – Known only to survive in captivity, or as a naturalized population outside its historic range
• Critically Endangered (CR) – Highest risk of extinction in the wild
• Endangered (EN) – Higher risk of extinction in the wild
• Vulnerable (VU) – High risk of extinction in the wild
• Near Threatened (NT) – Likely to become endangered in the near future
• Conservation Dependent (CD) – Low risk; is conserved to prevent being near threatened, certain events may lead it to being a higher risk level
• Least concern (LC) – Very low risk; does not qualify for a higher risk category and not likely to be threatened in the near future. Widespread and abundant taxa are included in this category.
• Data deficient (DD) – Not enough data to make an assessment of its risk of extinction
• Not evaluated (NE) – Has not yet been evaluated against the criteria.

The Convention on International Trade in Endangered Species of Wild Fauna and Flora

The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) went into force in 1975. It aims to ensure that international trade in specimens of wild animals and plants does not threaten their survival. Many countries require CITES permits when importing plants and animals listed on CITES.

Multi-country systems

In the European Union (EU), the Birds Directive and Habitats Directive are the legal instruments which evaluate the conservation status within the EU of species and habitats.

NatureServe conservation status focuses on Latin America, the United States, Canada, and the Caribbean. It has been developed by scientists from NatureServe, The Nature Conservancy, and a network of natural heritage programs and data centers. It is increasingly integrated with the IUCN Red List system. Its categories for species include: presumed extinct (GX), possibly extinct (GH), critically imperiled (G1), imperiled (G2), vulnerable (G3), apparently secure (G4), and secure (G5). The system also allows ambiguous or uncertain ranks including inexact numeric ranks (e.g. G2?), and range ranks (e.g. G2G3) for when the exact rank is uncertain. NatureServe adds a qualifier for captive or cultivated only (C), which has a similar meaning to the IUCN Red List extinct in the wild (EW) status.

The Red Data Book of the Russian Federation is used within the Russian Federation, and also accepted in parts of Africa.

National systems

In Australia, the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) describes lists of threatened species, ecological communities and threatening processes. The categories resemble those of the 1994 IUCN Red List Categories & Criteria (version 2.3). Prior to the EPBC Act, a simpler classification system was used by the Endangered Species Protection Act 1992. Some state and territory governments also have their own systems for conservation status. The codes for the Western Australian conservation system are given at Declared Rare and Priority Flora List (abbreviated to DECF when using in a taxobox).

In Belgium, the Flemish Research Institute for Nature and Forest publishes an online set of more than 150 nature indicators in Dutch.

In Canada, the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) is a group of experts that assesses and designates which wild species are in some danger of disappearing from Canada. Under the Species at Risk Act (SARA), it is up to the federal government, which is politically accountable, to legally protect species assessed by COSEWIC.

In China, the State, provinces and some counties have determined their key protected wildlife species. There is the China red data book.

In Finland, many species are protected under the Nature Conservation Act, and through the EU Habitats Directive and EU Birds Directive.

In Germany, the Federal Agency for Nature Conservation publishes "red lists of endangered species".

India has the Wild Life Protection Act, 1972, Amended 2003 and the Biological Diversity Act, 2002.

In Japan, the Ministry of Environment publishes a Threatened Wildlife of Japan Red Data Book.

In the Netherlands, the Dutch Ministry of Agriculture, Nature and Food Quality publishes a list of threatened species, and conservation is enforced by the Nature Conservation Act 1998. Species are also protected through the Wild Birds and Habitats Directives.

In New Zealand, the Department of Conservation publishes the New Zealand Threat Classification System lists. As of January 2008 threatened species or subspecies are assigned one of seven categories: Nationally Critical, Nationally Endangered, Nationally Vulnerable, Declining, Recovering, Relict, or Naturally Uncommon. While the classification looks only at a national level, many species are unique to New Zealand, and species which are secure overseas are noted as such.

In Russia, the Red Data Book of the Russian Federation came out in 2001, it contains categories defining preservation status for different species. In it there are 8 taxa of amphibians, 21 taxa of reptiles, 128 taxa of birds, and 74 taxa of mammals, in total 231. There are also more than 30 regional red books, for example the red book of the Altaic region which came out in 1994.

In South Africa, the South African National Biodiversity Institute, established under the National Environmental Management: Biodiversity Act, 2004, is responsible for drawing up lists of affected species, and monitoring compliance with CITES decisions. It is envisaged that previously diverse Red lists would be more easily kept current, both technically and financially.

In Thailand, the Wild Animal Reservation and Protection Act of BE 2535 defines fifteen reserved animal species and two classes of protected species, of which hunting, breeding, possession, and trade are prohibited or restricted by law. The National Park, Wildlife and Plant Conservation Department of the Ministry of Natural Resources and Environment is responsible for the regulation of these activities.

In Ukraine, the Ministry of Environment Protection maintains list of endangered species (divided into seven categories from "0" - extinct to "VI" - rehabilitated) and publishes it in the Red Book of Ukraine.

In the United States of America, the Endangered Species Act of 1973 created the Endangered Species List.

Consumer guides

Main article: Sustainable seafood advisory lists and certification

Some consumer guides for seafood, such as Seafood Watch, divide fish and other sea creatures into three categories, analogous to conservation status categories:

• Red ("say no" or "avoid")
• Yellow or orange ("think twice", "good alternatives" or "some concerns")
• Green ("best seafood choices")

The categories do not simply reflect the imperilment of individual species, but also consider the environmental impacts of how and where they are fished, such as through bycatch or ocean bottom trawlers. Often groups of species are assessed rather than individual species (e.g. squid, prawns).

The Marine Conservation Society has five levels of ratings for seafood species, as displayed on their FishOnline website.