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Topic Review
Evolutionary History of Life
The evolutionary history of life on Earth traces the processes by which living and fossil organisms evolved, from the earliest emergence of life to the present. Earth formed about 4.5 billion years (Ga) ago and evidence suggests life emerged prior to 3.7 Ga. (Although there is some evidence of life as early as 4.1 to 4.28 Ga, it remains controversial due to the possible non-biological formation of the purported fossils.) The similarities among all known present-day species indicate that they have diverged through the process of evolution from a common ancestor. Approximately 1 trillion species currently live on Earth of which only 1.75–1.8 million have been named and 1.6 million documented in a central database. These currently living species represent less than one percent of all species that have ever lived on earth. The earliest evidence of life comes from biogenic carbon signatures and stromatolite fossils discovered in 3.7 billion-year-old metasedimentary rocks from western Greenland. In 2015, possible "remains of biotic life" were found in 4.1 billion-year-old rocks in Western Australia. In March 2017, putative evidence of possibly the oldest forms of life on Earth was reported in the form of fossilized microorganisms discovered in hydrothermal vent precipitates in the Nuvvuagittuq Belt of Quebec, Canada, that may have lived as early as 4.28 billion years ago, not long after the oceans formed 4.4 billion years ago, and not long after the formation of the Earth 4.54 billion years ago. Microbial mats of coexisting bacteria and archaea were the dominant form of life in the early Archean Epoch and many of the major steps in early evolution are thought to have taken place in this environment. The evolution of photosynthesis, around 3.5 Ga, eventually led to a buildup of its waste product, oxygen, in the atmosphere, leading to the great oxygenation event, beginning around 2.4 Ga. The earliest evidence of eukaryotes (complex cells with organelles) dates from 1.85 Ga, and while they may have been present earlier, their diversification accelerated when they started using oxygen in their metabolism. Later, around 1.7 Ga, multicellular organisms began to appear, with differentiated cells performing specialised functions. Sexual reproduction, which involves the fusion of male and female reproductive cells (gametes) to create a zygote in a process called fertilization is, in contrast to asexual reproduction, the primary method of reproduction for the vast majority of macroscopic organisms, including almost all eukaryotes (which includes animals and plants). However the origin and evolution of sexual reproduction remain a puzzle for biologists though it did evolve from a common ancestor that was a single celled eukaryotic species. Bilateria, animals having a left and a right side that are mirror images of each other, appeared by 555 Ma (million years ago). The earliest complex land plants date back to around 850 Ma, from carbon isotopes in Precambrian rocks, while algae-like multicellular land plants are dated back even to about 1 billion years ago, although evidence suggests that microorganisms formed the earliest terrestrial ecosystems, at least 2.7 Ga. Microorganisms are thought to have paved the way for the inception of land plants in the Ordovician. Land plants were so successful that they are thought to have contributed to the Late Devonian extinction event. (The long causal chain implied seems to involve the success of early tree archaeopteris (1) drew down CO2 levels, leading to global cooling and lowered sea levels, (2) roots of archeopteris fostered soil development which increased rock weathering, and the subsequent nutrient run-off may have triggered algal blooms resulting in anoxic events which caused marine-life die-offs. Marine species were the primary victims of the Late Devonian extinction.) Ediacara biota appear during the Ediacaran period, while vertebrates, along with most other modern phyla originated about 525 Ma during the Cambrian explosion. During the Permian period, synapsids, including the ancestors of mammals, dominated the land, but most of this group became extinct in the Permian–Triassic extinction event 252 Ma. During the recovery from this catastrophe, archosaurs became the most abundant land vertebrates; one archosaur group, the dinosaurs, dominated the Jurassic and Cretaceous periods. After the Cretaceous–Paleogene extinction event 66 Ma killed off the non-avian dinosaurs, mammals increased rapidly in size and diversity. Such mass extinctions may have accelerated evolution by providing opportunities for new groups of organisms to diversify.
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Topic Review
Archaeogaming
Archaeogaming is an archaeological framework which, broadly speaking, includes the study of archaeology in and of video games as well as the use of video-games for archaeological purposes. To this end, the study can include, but is in no means limited to: the physical excavation of video-game hardware, the use of archaeological methods within game worlds, the creation of video-games for or about archaeological practices and outcomes or the critical study of how archaeology is represented in video-games. Virtual and augmented reality applications in archaeology might also be subsumed within its rubric. M. Dennis states that archaeogaming is “the utilization and treatment of immaterial space to study created culture, specifically through videogames” which “requires treating a game world, a world bounded and defined by the limitations of its hardware, software and coding choices, as both a closed universe and as an extension of the external culture that created it. Everything that goes into the immaterial space comes from its external cultural source, in one way or another.” Taking this into consideration the archaeogaming framework indicates that there is no functional difference between studying archaeology in the physical, material world, and implementing it with regards to the study, critique and creation of video-games for and about archaeology. As such it is said that archaeogaming “requires the same standards of practice as the physical collection of excavated data, only with a different toolset. It also provides the opportunity to use game worlds to reflect on practice, theory and the perceptions of [archaeology].”
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Topic Review
Geodetic Datum
A geodetic datum or geodetic system (also: geodetic reference datum or geodetic reference system) is a coordinate system, and a set of reference points, used for locating places on the Earth (or similar objects). An approximate definition of sea level is the datum WGS 84, an ellipsoid, whereas a more accurate definition is Earth Gravitational Model 2008 (EGM2008), using at least 2,159 spherical harmonics. Other datums are defined for other areas or at other times; ED50 was defined in 1950 over Europe and differs from WGS 84 by a few hundred meters depending on where in Europe you look. Mars has no oceans and so no sea level, but at least two martian datums have been used to locate places there. Datums are used in geodesy, navigation, and surveying by cartographers and satellite navigation systems to translate positions indicated on maps (paper or digital) to their real position on Earth. Each starts with an ellipsoid (stretched sphere), and then defines latitude, longitude and altitude coordinates. One or more locations on the Earth's surface are chosen as anchor "base-points". The difference in co-ordinates between datums is commonly referred to as datum shift. The datum shift between two particular datums can vary from one place to another within one country or region, and can be anything from zero to hundreds of meters (or several kilometers for some remote islands). The North Pole, South Pole and Equator will be in different positions on different datums, so True North will be slightly different. Different datums use different interpolations for the precise shape and size of the Earth (reference ellipsoids). Because the Earth is an imperfect ellipsoid, localised datums can give a more accurate representation of the area of coverage than WGS 84. OSGB36, for example, is a better approximation to the geoid covering the British Isles than the global WGS 84 ellipsoid. However, as the benefits of a global system outweigh the greater accuracy, the global WGS 84 datum is becoming increasingly adopted. Horizontal datums are used for describing a point on the Earth's surface, in latitude and longitude or another coordinate system. Vertical datums measure elevations or depths.
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Topic Review
1968 Burma Cyclone
The 1968 Burma cyclone was regarded as the worst to strike the country during the 20th century before it was surpassed by another unnamed cyclone in 2004 and further, Cyclone Nargis in 2008, respectively. The first tropical cyclone of the 1968 North Indian Ocean cyclone season, it started as a depression on May 7 on the northern Andaman Sea. With low wind shear and warm sea surface temperatures, the storm intensified in the waters near Burma before heading northwestwards. It then started to rapidly intensify, with an eye becoming apparent on satellite imagery on May 9. Also that day, it reached its peak intensity, with 3-minute maximum sustained winds of 220 km/h (140 mph) by the Indian Meteorological Department, which is equivalent to a super cyclonic storm; however, the agency treated the system as a severe cyclonic storm. Little to no changes happened on the cyclone as it turned northeastwards, making landfall near Akyab (now Sittwe) between 18:00 and 21:00 UTC on that day. Land interaction rapidly weakened the storm, dissipating on May 10 as an area of low-pressure in south Chin State. The predecessor to the cyclone caused light to moderate downpour to the Andaman Islands; however, no deaths were reported. Winds reported from the cyclone inland Burma reached an estimate of 60–100 mph, altogether with heavy rainfall and large storm surges. The former flooded the crops, submerging them in floodwaters in the process while the latter washed out villages near the path of the storm. Schools and hospitals throughout Akyab were destroyed by high winds and large waves, while the port suffered major damages. The town was almost destroyed due to the storm. In addition, some ships in the said harbor, including the Greek freighter Geros Michalos were reportedly sunk in the Bay of Bengal. Houses were destroyed during the storm and many livestock died, mainly due to drowning. The death toll from the cyclone was finalized on May 1968 at 1,307 individuals, while 2,000 more were reportedly missing. The property damages were estimated at K15 million kyat ($3.248 million United States dollar ). After the cyclone, the Government of Burma started to release aid to the victims, altogether with food supplies and cotton blankets. The Red Cross Society of the country donated cases of medicines to the country, while the United States Government released over 25,000 blankets to be transferred to the area. In addition, many countries and organizations including the UNICEF contributed over $121,291 (1968 USD) to Myanmar, following the disaster.
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Topic Review
2020–2021 Taal Volcano Eruptions
Taal Volcano in Batangas, Philippines began to erupt on January 12, 2020, when a phreatomagmatic eruption from its main crater spewed ashes over Calabarzon, Metro Manila, and some parts of Central Luzon and Ilocos Region, resulting in the suspension of school classes, work schedules, and flights in the area. The Philippine Institute of Volcanology and Seismology (PHIVOLCS) subsequently issued an Alert Level 4, indicating "that a hazardous explosive eruption is possible within hours to days." Volcanic activity continued into 2021, when smaller eruptions occurred in July 2021.
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Topic Review
WISDOM Project
The WISDOM Project is a bilateral research project between Germany and Vietnam, focusing on the creation of a Water related Information System for the Mekong Delta. Initiated by the Vietnamese and the German Government it was started in the year 2007, and is planned to continue until the year 2013. Water-related Information System for the sustainable Development of the Mekong Delta in Vietnam
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Topic Review
Burmese Amber
Burmese amber, also known as Burmite or Kachin amber, is amber from the Hukawng Valley in northern Myanmar. The amber is dated to around 99 million years old, during the earliest part of the Cenomanian age of the Late Cretaceous. The amber is of significant palaeontological interest due to the diversity of flora and fauna contained as inclusions, particularly arthropods including insects and arachnids but also birds, lizards, snakes, frogs and fragmentary dinosaur remains. The amber has been known and commercially exploited since the first century AD, and has been known to science since the mid-nineteenth century. Research on the deposit has attracted controversy due to its role in funding internal conflict in Myanmar and hazardous working conditions in the mines where it is collected.
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Topic Review
Biochronology
In paleontology, biochronology is the correlation in time of biological events using fossils. In its strict sense, it refers to the use of assemblages of fossils that are not tied to stratigraphic sections (in contrast to biostratigraphy, where they are). Collections of land mammal ages have been defined for every continent except Antarctica, and most are correlated with each other indirectly through known evolutionary lineages. A combination of argon–argon dating and magnetic stratigraphy allows a direct temporal comparison of terrestrial events with climate change and mass extinctions.
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Topic Review
Galápagos Islands
The Galápagos Islands (official name: Archipiélago de Colón, other Spanish name: Las Islas Galápagos, Spanish pronunciation: [las ˈislas ɣaˈlapaɣos], local pronunciation: [laz ˈihlah ɣaˈlapaɣoh]), part of the Republic of Ecuador, are an archipelago of volcanic islands distributed on either side of the equator in the Pacific Ocean surrounding the centre of the Western Hemisphere. Located 906 km (563 mi) west of continental Ecuador, the islands are known for their large number of endemic species that were studied by Charles Darwin during the second voyage of HMS Beagle. His observations and collections contributed to the inception of Darwin's theory of evolution by means of natural selection. The Galápagos Islands and their surrounding waters form the Galápagos Province of Ecuador, the Galápagos National Park, and the Galápagos Marine Reserve. The principal language on the islands is Spanish. The islands have a population of slightly over 25,000. The first recorded visit to the islands happened by chance in 1535, when Fray Tomás de Berlanga, the Bishop of Panamá, was surprised with this undiscovered land during a voyage to Peru to arbitrate in a dispute between Francisco Pizarro and Diego de Almagro. De Berlanga eventually returned to the Spanish Empire and described the conditions of the islands and the animals that inhabited them. The group of islands was shown and named "Insulae de los Galopegos" (Islands of the Tortoises) in Abraham Ortelius's atlas published in 1570. The first crude map of the islands was made in 1684 by the buccaneer Ambrose Cowley, who named the individual islands after some of his fellow pirates or after British royalty and noblemen. These names were used in the authoritative navigation charts of the islands prepared during the Beagle survey under captain Robert FitzRoy, and in Darwin's popular book The Voyage of the Beagle. The newly independent Republic of Ecuador took the islands from Spanish ownership in 1832, and subsequently gave them official Spanish names. The older names remained in use in English-language publications, including Herman Melville's The Encantadas of 1854. Administratively, Galapagos constitutes one of the provinces of Ecuador, made up of three cantons that bear the names of its most populated islands, namely: San Cristóbal, Santa Cruz and Isabela.
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Topic Review
Northern Cheyenne Indian Reservation
The Northern Cheyenne Tribe of the Northern Cheyenne Indian Reservation (Template:Lang-chy; formerly named the Tongue River) is the federally recognized Northern Cheyenne tribe. Located in southeastern Montana, the reservation is approximately 690 square miles (1,800 km2) in size and home to approximately 5,000 Cheyenne people. The tribal and government headquarters are located in Lame Deer, also the home of the annual Northern Cheyenne pow wow. The reservation is bounded on the east by the Tongue River and on the west by the Crow Reservation. There are small parcels of non-contiguous off-reservation trust lands in Meade County, South Dakota, northeast of the city of Sturgis. Its timbered ridges that extend into northwestern South Dakota are part of Custer National Forest and it is approximately 40 miles (64 km) east of the site of the 1876 Battle of the Little Bighorn. According to tribal enrollment figures as of March 2013, there were approximately 10,050 enrolled tribal members, of which about 4,939 were residing on the reservation,Template:Full short with approximately 91% of the population Native American (full or part blood quantum) and 72.8% identifying as Cheyenne. Slightly more than a quarter of the population five years or older spoke a language other than English. Members of the Crow Nation also live on the reservation.
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