question: How does an insect becomes preserved in amber?
comment: 1. Insect lands on tree 2. Resin flows and it's sticky: URL_0 3. Resin solidifies Insect remains there in the resin, intact. Amber is just solidified resin from trees, that was buried under ground for a long time.
passages: Section::::Plot summary.:Paris, 1744.
   Once the material has been obtained, depending on what it is, there are different ways to isolate and purify it. DNA extraction from fossils is one of the more popular practices and there are different steps that can be taken to get the desired sample. DNA extracted from amber-entombed fossils can be taken from small samples and mixed with different substances, centrifuged, incubated, and centrifuged again. On the other hand, DNA extraction from insects can be done by grinding the sample, mixing it with buffer, and undergoing purification through glass fiber columns. In the end, regardless of how the sample was isolated for these fossils, the DNA isolated must be able to undergo amplification.
   Heated above , amber decomposes, yielding an oil of amber, and leaves a black residue which is known as "amber colophony", or "amber pitch"; when dissolved in oil of turpentine or in linseed oil this forms "amber varnish" or "amber lac".
  
  Section::::Composition and formation.:Formation.
  
  Molecular polymerization, resulting from high pressures and temperatures produced by overlying sediment, transforms the resin first into copal. Sustained heat and pressure drives off terpenes and results in the formation of amber.
   Section::::Plot summary.:1968.
   Section::::Classification.:Class I.:Ib.
  
  Like class Ia ambers, these are based on communic acid; however, they lack succinic acid.
  
  Section::::Classification.:Class I.:Ic.
  
  This class is mainly based on "enantio"-labdatrienonic acids, such as ozic and zanzibaric acids. Its most familiar representative is Dominican amber.
   When an insect is partly or wholly replaced by minerals, usually completely articulated and with three-dimensional fidelity, is called "mineral replication". This is also called petrifaction, as in “petrified” wood. Insects preserved this way are often, but not always, preserved as concretions, or within nodules of minerals that formed around the insect as its nucleus. Such deposits generally form where the sediments and water are laden with minerals, and where there is also quick mineralization of the carcass by coats of bacteria.
  
  Section::::Evolutionary history.
   In an important example of co-evolution, a number of highly successful insect groups — especially the Hymenoptera (wasps, bees and ants) and Lepidoptera (butterflies) as well as many types of Diptera (flies) and Coleoptera (beetles) — evolved in conjunction with flowering plants during the Cretaceous (145 to 66 million years ago).
  
  Many modern insect genera developed during the Cenozoic that began about 66 million years ago; insects from this period onwards frequently became preserved in amber, often in perfect condition. Such specimens are easily compared with modern species, and most of them are members of extant genera.
  
  Section::::Fossils.
  
  Section::::Fossils.:Preservation.
   Pliny also cites the opinion of Nicias ( 470–413 BC), according to whom amber Besides the fanciful explanations according to which amber is "produced by the Sun", Pliny cites opinions that are well aware of its origin in tree resin, citing the native Latin name of "succinum" ("sūcinum", from "sucus" "juice"). In Book 37, section XI of "Natural History", Pliny wrote:
   BULLET::::- Insect and plant inclusions are reported from amber from the uppermost Campanian Kabaw Formation of Tilin (Myanmar) by Zheng "et al." (2018).
  
  BULLET::::- Taphonomic study aiming to determine whether decay and preservation potential of insects in amber, and therefore bias in the amber fossil record, is affected by resin-type, dehydration prior to entombment, and the composition of the gut microbiota, is published by McCoy "et al." (2018).
  
  BULLET::::- A study on the evolution of insects as indicated by the morphological diversity of their mouthparts is published by Nel, Bertrand & Nel (2018).
   Section::::Insect development during autopsy.
   Amber sometimes contains animals or plant matter that became caught in the resin as it was secreted. Insects, spiders and even their webs, annelids, frogs, crustaceans, bacteria and amoebae, marine microfossils, wood, flowers and fruit, hair, feathers and other small organisms have been recovered in Cretaceous ambers (deposited c. ). The oldest amber to bear fossils (mites) is from the Carnian (Triassic, ) of north-eastern Italy.
   The preservation of prehistoric organisms in amber forms a key plot point in Michael Crichton's 1990 novel "Jurassic Park" and the 1993 movie adaptation by Steven Spielberg. In the story, scientists are able to extract the preserved blood of dinosaurs from prehistoric mosquitoes trapped in amber, from which they genetically clone living dinosaurs. Scientifically this is as yet impossible, since no amber with fossilized mosquitoes has ever yielded preserved blood. Amber is, however, conducive to preserving DNA, since it dehydrates and thus stabilizes organisms trapped inside. One projection in 1999 estimated that DNA trapped in amber could last up to 100 million years, far beyond most estimates of around 1 million years in the most ideal conditions, although a later 2013 study was unable to extract DNA from insects trapped in much more recent Holocene copal.
   In ancient China, it was customary to burn amber during large festivities. If amber is heated under the right conditions, oil of amber is produced, and in past times this was combined carefully with nitric acid to create "artificial musk" – a resin with a peculiar musky odor. Although when burned, amber does give off a characteristic "pinewood" fragrance, modern products, such as perfume, do not normally use actual amber due to the fact that fossilized amber produces very little scent. In perfumery, scents referred to as "amber" are often created and patented
   Section::::Preparation.:Wet specimen.
  
  A wet specimen is a specimen preserved in fluid, often 70% alcohol. Specimens that would receive this preservation technique are usually soft-bodied, such as caterpillars, larva, and spiders because of their soft abdomens. This is done to minimize shriveling allowing the identifying characteristics to be preserved as true to life as possible. Hard-bodied insects may also be preserved temporarily in alcohol before pinning.
  
  Section::::Preparation.:Slides.
  
  Slides of very small insects are also kept as part of insect collections.
  
  Section::::Core aspects of conservation.
   There are five classes of amber, defined on the basis of their chemical constituents. Because it originates as a soft, sticky tree resin, amber sometimes contains animal and plant material as inclusions. Amber occurring in coal seams is also called resinite, and the term ambrite is applied to that found specifically within New Zealand coal seams.
  
  Section::::Etymology.
   BULLET::::- An amber layer is reported from the lower part of the Dingqing Formation (late Oligocene) in Lunpola of central Tibet (representing the first record of amber from Tibet) by Wang "et al." (2018), who interpret this amber as derived from dipterocarp trees, and who interpret the amber layer as remains of the northernmost dipterocarp forest discovered so far.
  
  BULLET::::- A study on CO concentrations during the early Miocene, as indicated by stomatal characteristics of fossil leaves from a late early Miocene assemblage from Panama and a leaf gas‐exchange model, is published by Londoño "et al." (2018).
   Section::::Development.:Pregnancy.
   BULLET::::- "Aphaenogaster praerelicta" (an ant)
  
  BULLET::::- "Culoptila aguilerai" (a caddisfly)
  
  BULLET::::- "Dicromantispa electromexicana" (a mantidfly)
  
  BULLET::::- "Hyptia deansi" (a wasp)
  
  BULLET::::- "Leptopharsa tacanae" (a lace bug)
  
  BULLET::::- "Maatidesmus paachtun" (a milliede)
  
  BULLET::::- "Mastotermes electromexicus" (a termite)
  
  BULLET::::- "Parastemmiulus elektron" (a millipede)
  
  BULLET::::- "Schwenckfeldina archoica" (a fungus gnat)
  
  BULLET::::- "Termitaradus protera" (a termite bug)
  
  BULLET::::- "Tonocatecutlius sp." (a planthopper)
  
  BULLET::::- "Tityus apozonalli" (a scorpion)
  
  BULLET::::- "Tityus knodeli" (a scorpion)
  
  BULLET::::- "Tesserocerus simojovelensis" Peris and Solórzano Kraemer 2015 (ambrosia beetle)
  
  BULLET::::- "Cenocephalus tenuis" Peris and Solórzano Kraemer 2015 (ambrosia beetle)
  
  BULLET::::- "Mesorhaga pseudolacrymans" Bickel 2016 (long-legged fly)
   He also states that amber is also found in Egypt and in India, and he even refers to the electrostatic properties of amber, by saying that "in Syria the women make the whorls of their spindles of this substance, and give it the name of "harpax" [from ἁρπάζω, "to drag"] from the circumstance that it attracts leaves towards it, chaff, and the light fringe of tissues".
   The oldest amber recovered dates to the Upper Carboniferous period (). Its chemical composition makes it difficult to match the amber to its producers – it is most similar to the resins produced by flowering plants; however, there are no flowering plant fossils known from before the Cretaceous, and they were not common until the Late Cretaceous. Amber becomes abundant long after the Carboniferous, in the Early Cretaceous, , when it is found in association with insects. The oldest amber with arthropod inclusions comes from the Levant, from Lebanon and Jordan. This amber, roughly 125–135 million years old, is considered of high scientific value, providing evidence of some of the oldest sampled ecosystems.
   BULLET::::- A study on extant arthropods (mainly insects and spiders) living around the resinous tree "Hymenaea verrucosa" in the lowland coastal forest of Madagascar and trapped by the resin produced by this tree species, and on their implications for inferring whether amber records the true past biodiversity of the entire forest, is published by Solórzano Kraemer "et al." (2018).
  
  BULLET::::- A study on the early evolution of stem and crown-arthropods as indicated by Ediacaran and Cambrian body and trace fossils is published by Daley "et al." (2018).
   BULLET::::- A study on the evolution of ecdysozoan vision, focusing on the evolution of arthropod multi-opsin vision, as indicated by molecular data and data from fossil record, is published by Fleming "et al." (2018).
  
  BULLET::::- Grimaldi "et al." (2018) report biological inclusions (fungi, plants, arachnids and insects) in amber from the Paleogene Chickaloon Formation of Alaska, representing the northernmost deposit of fossiliferous amber from the Cenozoic.
   Many fossilised insects were observed in Sarawak amber, trapped approximately 20 million years ago when the resin was initially accumulated and perfectly preserved to this day. So far, the insects found in amber were spiders, ants, mosquitoes, centipedes, wasps and beetles. The colours of amber vary from black to whitish and sometimes with shades of orange, red, yellow and brown. They can be either opaque or transparent.
  
  Section::::Museum.:Weaving / Handicraft Workshop.
   The Vienna amber factories, which use pale amber to manufacture pipes and other smoking tools, turn it on a lathe and polish it with whitening and water or with rotten stone and oil. The final luster is given by friction with flannel.
  
  When gradually heated in an oil-bath, amber becomes soft and flexible. Two pieces of amber may be united by smearing the surfaces with linseed oil, heating them, and then pressing them together while hot. Cloudy amber may be clarified in an oil-bath, as the oil fills the numerous pores to which the turbidity is due.
   The documentary shows Attenborough searching for the identities of preserved creatures inside a piece of Baltic amber that was given to him by his adoptive sister when he was twelve years old. It then shows how a group of scientists can reconstruct an entire twenty million-year-old ecosystem through pieces of Dominican amber. Examples include a tadpole preserved in amber after falling from a bromeliad.
  