The Living Remain
Living things may be distinguished from non-living things in their ability to carry on life processes such as movement, respiration, growth, responsiveness to environmental stimuli and reproduction. This view of living may be appropriate at this age but has some limitations and can lead to the alternative conceptions above. For example movement in plants is not apparent to students and consequently they may not consider plants living.
The Living Remain
Decisions about whether things are alive or non-living remain problematic as not all life processes stop at the same time. For example, human fingernails and hair continue to grow for weeks after death.
Legends of the living dead go back to 11th-century Europe. People feared that some of those buried would make their way back to the surface on Easter day as blood-sucking monsters, terrifying the living.
Researchers who made the discovery said that when they were placed in burials a scythe was a guarantee that the deceased would remain in their graves and therefore could not harm the living, but they may have also served to protect the dead from evil forces.
The U.S. based air filter replacement brand ranked 55 metropolitan areas around the country on cost of living increases over the last decade, and found that the Philly/Camden/Wilmington metro area has seen the fourth lowest rise overall.
The company only tracked cities with more than 100,000 residents, and organized them in the report by size. The Seattle metropolitan area saw the largest cost of living increase, at 23.2%, with Denver, Portland, and Miami close behind.
Philadelphia's metropolitan area saw an 11.5% increase in cost of living from 2010 through 2020, along with a 2.3% increase in the overall cost of living. The report also observed that the Philly metropolitan area saw a 4.4% decrease in the cost of goods, as well as a 0.7% decrease in the cost of utilities.
Although these guidelines were intended for living subjects, they provide a framework to consider research on the dead. After all, research on the dead ultimately affects the living. One way to ensure these protections is to seek informed consent from individuals, kin, communities or legal authorities before conducting studies.
Memory Forests are beautiful, tranquil resting places for our loved ones full of trees and life! We plant a memory tree with your loved ones cremated remains and The Living Urn to grow a beautiful, enduring living memorial that will be cared for and endure for generations to come!
Come to Memory Forest to visit a loved one's living memorial. We're creating beautiful, serene landscapes to gather friends and family, to pay honor, to heal and remember. We're developing special options, including artistic memorials and technology that will let you view a memory tree from anywhere, anytime!
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.
Such criteria are neither well-defined nor clearly quantifiable, but modern methods for analyzing evolutionary dynamics can document the distinctive tempo of stasis. Lineages that exhibit stasis over very short time scales are not considered living fossils; what is poorly-defined is the time scale over which the morphology must persist for that lineage to be recognized as a living fossil.
The term "living fossil" is much misunderstood in popular media in particular, in which it often is used meaninglessly. In professional literature the expression seldom appears and must be used with far more caution, although it has been used inconsistently.
One example of a concept that could be confused with "living fossil" is that of a "Lazarus taxon", but the two are not equivalent; a Lazarus taxon (whether a single species or a group of related species) is one that suddenly reappears, either in the fossil record or in nature, as if the fossil had "come to life again". In contrast to "Lazarus taxa", a living fossil in most senses is a species or lineage that has undergone exceptionally little change throughout a long fossil record, giving the impression that the extant taxon had remained identical through the entire fossil and modern period. Because of the mathematical inevitability of genetic drift, though, the DNA of the modern species is necessarily different from that of its distant, similar-looking ancestor. They almost certainly would not be able to cross-reproduce, and are not the same species.
Coelacanths disappeared from the fossil record some 80 million years ago (upper Cretaceous) and, to the extent that they exhibit low rates of morphological evolution, extant species qualify as living fossils. It must be emphasised that this criterion reflects fossil evidence, and is totally independent of whether the taxa had been subject to selection at all, which all living populations continuously are, whether they remain genetically unchanged or not.
The fact that a living fossil is a surviving representative of an archaic lineage does not imply that it must retain all the "primitive" features (plesiomorphies) of its ancestral lineage. Although it is common to say that living fossils exhibit "morphological stasis", stasis, in the scientific literature, does not mean that any species is strictly identical to its ancestor, much less remote ancestors.
Some living fossils are relicts of formerly diverse and morphologically varied lineages, but not all survivors of ancient lineages necessarily are regarded as living fossils. See for example the uniquely and highly autapomorphic oxpeckers, which appear to be the only survivors of an ancient lineage related to starlings and mockingbirds.
The term living fossil is usually reserved for species or larger clades that are exceptional for their lack of morphological diversity and their exceptional conservatism, and several hypotheses could explain morphological stasis on a geologically long time-scale. Early analyses of evolutionary rates emphasized the persistence of a taxon rather than rates of evolutionary change. Contemporary studies instead analyze rates and modes of phenotypic evolution, but most have focused on clades that are thought to be adaptive radiations rather than on those thought to be living fossils. Thus, very little is presently known about the evolutionary mechanisms that produce living fossils or how common they might be. Some recent studies have documented exceptionally low rates of ecological and phenotypic evolution despite rapid speciation. This has been termed a "non-adaptive radiation" referring to diversification not accompanied by adaptation into various significantly different niches. Such radiations are explanation for groups that are morphologically conservative. Persistent adaptation within an adaptive zone is a common explanation for morphological stasis. The subject of very low evolutionary rates, however, has received much less attention in the recent literature than that of high rates
... All fresh-water basins, taken together, make a small area compared with that of the sea or of the land; and, consequently, the competition between fresh-water productions will have been less severe than elsewhere; new forms will have been more slowly formed, and old forms more slowly exterminated. And it is in fresh water that we find seven genera of Ganoid fishes, remnants of a once preponderant order: and in fresh water we find some of the most anomalous forms now known in the world, as the Ornithorhynchus and Lepidosiren, which, like fossils, connect to a certain extent orders now widely separated in the natural scale. These anomalous forms may almost be called living fossils; they have endured to the present day, from having inhabited a confined area, and from having thus been exposed to less severe competition.
This is a more neutral definition. However, it does not make it clear whether the taxon is truly old, or it simply has many plesiomorphies. Note that, as mentioned above, the converse may hold for true living fossil taxa; that is, they may possess a great many derived features (autapomorphies), and not be particularly "primitive" in appearance.
Some paleontologists believe that living fossils with large distributions (such as Triops cancriformis) are not real living fossils. In the case of Triops cancriformis (living from the Triassic until now), the Triassic specimens lost most of their appendages (mostly only carapaces remain), and they have not been thoroughly examined since 1938.
The two living species thus seem to represent an entirely extinct and (as Passerida go) rather ancient lineage, as certainly as this can be said in the absence of actual fossils. The latter is probably due to the fact that the oxpecker lineage never occurred in areas where conditions were good for fossilization of small bird bones, but of course, fossils of ancestral oxpeckers may one day turn up enabling this theory to be tested.
An operational definition was proposed in 2017, where a 'living fossil' lineage has a slow rate of evolution and occurs close to the middle of morphological variation (the centroid of morphospace) among related taxa (i.e. a species is morphologically conservative among relatives). The scientific accuracy of the morphometric analyses used to classify tuatara as a living fossil under this definition have been criticised however, which prompted a rebuttal from the original authors.
The popularity of living-organ donation has increased dramatically in recent years as an alternative to deceased-organ donation due to the growing need for organs for transplantation and shortage of available deceased-donor organs. More than 5,700 living-organ donations are reported each year in the United States. 041b061a72