|
Elvis Taxon
In paleontology, an Elvis taxon (plural ''Elvis taxa'') is a taxon that has been misidentified as having re-emerged in the fossil record after a period of presumed extinction, but is not actually a descendant of the original taxon, instead having developed a similar morphology by convergent evolution. This implies that the extinction of the original taxon is real, and one taxon containing specimens from before and after the extinction would be polyphyletic. Etymology The term "Elvis taxon" was coined by D. H. Erwin and M. L. Droser in a 1993 paper to distinguish descendant from non-descendant taxa: Related but distinctive concepts By contrast, a Lazarus taxon is one that really is a descendant of the original taxon, and highlights transitional fossil records, which might be found later. A zombie taxon has been considered a Lazarus taxon because it has been collected from younger strata, but it later turns out to be a fossil that was freed from the original seam and was refoss ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleontology
Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossils to classify organisms and study their interactions with each other and their environments (their paleoecology). Paleontological observations have been documented as far back as the 5th century BC. The science became established in the 18th century as a result of Georges Cuvier's work on comparative anatomy, and developed rapidly in the 19th century. The term itself originates from Greek (, "old, ancient"), (, ( gen. ), "being, creature"), and (, "speech, thought, study"). Paleontology lies on the border between biology and geology, but differs from archaeology in that it excludes the study of anatomically modern humans. It now uses techniques drawn from a wide range of sciences, including biochemistry, mathematics, and engineering. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brachiopod
Brachiopods (), phylum Brachiopoda, are a phylum of trochozoan animals that have hard "valves" (shells) on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear end, while the front can be opened for feeding or closed for protection. Two major categories are traditionally recognized, articulate and inarticulate brachiopods. The word "articulate" is used to describe the tooth-and-groove structures of the valve-hinge which is present in the articulate group, and absent from the inarticulate group. This is the leading diagnostic skeletal feature, by which the two main groups can be readily distinguished as fossils. Articulate brachiopods have toothed hinges and simple, vertically-oriented opening and closing muscles. Conversely, inarticulate brachiopods have weak, untoothed hinges and a more complex system of vertical and oblique (diagonal) muscles used to keep the two valves aligned. In many brachiopods, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extinction
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point. Because a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as Lazarus taxa, where a species presumed extinct abruptly "reappears" (typically in the fossil record) after a period of apparent absence. More than 99% of all species that ever lived on Earth, amounting to over five billion species, are estimated to have died out. It is estimated that there are currently around 8.7 million species of eukaryote globally, and possibly many times more if microorganisms, like bacteria, are included. Notable extinct animal species include non-avian dinosaurs, saber-toothed cats, dodos, m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sightings Of Elvis Presley
Sightings of the American singer Elvis Presley have been reported following his death in 1977. The conspiracy theory that Elvis did not die and instead went into hiding was popularized by Gail Brewer-Giorgio and other authors. Notable sighting claims The earliest known alleged sighting of Elvis was at the Memphis International Airport where a man resembling Elvis gave the name "Jon Burrows", which was the same name Elvis used when booking hotels. A series of alleged sightings took place in Kalamazoo, Michigan, in the late 1980s. Such reports encountered public ridicule and became fodder for humorous publications like the ''Weekly World News''. In California, many people believed they had seen Elvis at California's Legoland amusement park shortly after opening in 1999. It was later revealed that Elvis impersonators were hired as an attraction to commemorate Presley. Elvis was rumored to have appeared in the background of an airport scene in the 1990 film ''Home Alone''. It was a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Living Fossil
A living fossil is an extant taxon that cosmetically resembles related species known only from the fossil record. To be considered a living fossil, the fossil species must be old relative to the time of origin of the extant clade. Living fossils commonly are of species-poor lineages, but they need not be. While the body plan of a living fossil remains superficially similar, it is never the same species as the remote relatives it resembles, because genetic drift would inevitably change its chromosomal structure. Living fossils exhibit stasis (also called "bradytely") over geologically long time scales. Popular literature may wrongly claim that a "living fossil" has undergone no significant evolution since fossil times, with practically no molecular evolution or morphological changes. Scientific investigations have repeatedly discredited such claims. The minimal superficial changes to living fossils are mistakenly declared as an absence of evolution, but they are examples of s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iterative Evolution
De-extinction (also known as resurrection biology, or species revivalism) is the process of generating an organism that either resembles or ''is'' an extinct species. There are several ways to carry out the process of de-extinction. Cloning is the most widely proposed method, although genome editing and selective breeding have also been considered. Similar techniques have been applied to certain endangered species, in hopes to boost their genetic diversity. The only method of the three that would provide an animal with the same genetic identity is cloning. There are benefits and malefits to the process of de-extinction ranging from technological advancements to ethical issues. Methods Cloning Cloning is a commonly suggested method for the potential restoration of an extinct species. It can be done by extracting the nucleus from a preserved cell from the extinct species and swapping it into an egg, without a nucleus, of that species' nearest living relative. The egg can then be i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rallidae
The rails, or Rallidae, are a large cosmopolitan family of small- to medium-sized, ground-living birds. The family exhibits considerable diversity and includes the crakes, coots, and gallinules. Many species are associated with wetlands, although the family is found in every terrestrial habitat except dry deserts, polar regions, and alpine areas above the snow line. Members of the Rallidae occur on every continent except Antarctica. Numerous island species are known. The most common rail habitats are marshland and dense forest. They are especially fond of dense vegetation.Horsfall & Robinson (2003): pp. 206–207 Name "Rail" is the anglicized respelling of the French ''râle'', from Old French ''rasle''. It is named from its harsh cry, in Vulgar Latin *''rascula'', from Latin ''rādere'' ("to scrape"). Morphology The rails are a family of small to medium-sized, ground-living birds. They vary in length from and in weight from . Some species have long necks and in many ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aldabra
Aldabra is the world's second-largest coral atoll, lying south-east of the continent of Africa. It is part of the Aldabra Group of islands in the Indian Ocean that are part of the Outer Islands of the Seychelles, with a distance of 1,120 km (700 mi) southwest of the capital, Victoria on Mahé Island. History The name Aldabra, originally Al-Hadra or Al-Khadra (with several variants), was given by Arab seafarers for "the atoll’s harsh, sun-baked environment"; this name was included in the Portuguese maps of the 16th century. The islands were already known to the Persians and Arabs, from whom they got their name. They had named the Indian Ocean as Bahr-el zanj. It was visited by Portuguese navigators in 1511. In the middle of the 18th century, the atoll became a dependency of the French colony of Réunion, from where expeditions were made for the capture of the Aldabra giant tortoises. As there are no surface freshwater sources on Aldabra, the interests of the explor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Level Rise
Globally, sea levels are rising due to human-caused climate change. Between 1901 and 2018, the globally averaged sea level rose by , or 1–2 mm per year on average.IPCC, 2019Summary for Policymakers InIPCC Special Report on the Ocean and Cryosphere in a Changing Climate .-O. Pörtner, D.C. Roberts, V. Masson-Delmotte, P. Zhai, M. Tignor, E. Poloczanska, K. Mintenbeck, A. Alegría, M. Nicolai, A. Okem, J. Petzold, B. Rama, N.M. Weyer (eds.) Cambridge University Press, Cambridge, UK and New York, NY, USA. https://doi.org/10.1017/9781009157964.001. This rate is accelerating, with sea levels now rising by 3.7 mm per year. Climate scientists expect further acceleration during the 21st century. Climate change heats (and therefore expands) the ocean and melts land-based ice sheets and glaciers. Between 1993 and 2018, the thermal expansion of water contributed 42% to sea level rise; melting of temperate glaciers, 21%; Greenland, 15%; and Antarctica, 8%. Over the next 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
_01_svg.svg "Click for more on -> Brachiopod")
.jpg "Click for more on -> Extinction")
