Extinctionis the termination of ataxonby thedeathof itslast member.A taxon may becomefunctionally extinctbefore the death of its last member if it loses the capacity toreproduceand recover. Because a species' potentialrangemay be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such asLazarus taxa,where a species presumed extinct abruptly "reappears" (typically in thefossil record) after a period of apparent absence.

Thethylacine(Thylacinus cynocephalus) is an example of an extinct species.

More than 99% of allspeciesthat everlivedonEarth,amounting to over five billion species,[1]are estimated to havediedout.[2][3][4][5]It is estimated that there are currently around 8.7 million species ofeukaryotesglobally,[6]and possibly many times more ifmicroorganisms,likebacteria,are included.[7]Notable extinct animal species includenon-avian dinosaurs,saber-toothed cats,dodos,mammoths,ground sloths,thylacines,trilobites,golden toads,andpassenger pigeons.

Throughevolution,species arise through the process ofspeciation—where new varieties of organisms arise and thrive when they are able to find and exploit anecological niche—and species become extinct when they are no longer able to survive in changing conditions or against superiorcompetition.The relationship between animals and their ecological niches has been firmly established.[8]A typical species becomes extinct within 10 million years of its first appearance,[5]although some species, calledliving fossils,survive with little to nomorphologicalchange for hundreds of millions of years.

Mass extinctionsare relatively rare events; however, isolated extinctions of species and clades are quite common, and are a natural part of the evolutionary process.[9]Only recently have extinctions been recorded and scientists have become alarmed at thecurrent high rate of extinctions.[10][11][12][13][14]Most species that become extinct are never scientifically documented. Some scientists estimate that up to half of presently existing plant and animal species may become extinct by 2100.[15]A 2018 report indicated that thephylogenetic diversityof 300 mammalian species erased during the human era since theLate Pleistocenewould require 5 to 7 million years to recover.[16]

According to the 2019Global Assessment Report on Biodiversity and Ecosystem ServicesbyIPBES,the biomass of wild mammals has fallen by 82%, natural ecosystems have lost about half their area and a million species are at risk of extinction—all largely as a result of human actions. Twenty-five percent of plant and animal species arethreatenedwith extinction.[17][18][19]In a subsequent report, IPBES listed unsustainable fishing, hunting and logging as being some of the primary drivers of the global extinction crisis.[20]

In June 2019, one million species of plants and animals were at risk of extinction. At least 571 plant species have been lost since 1750, but likely many more. The main cause of the extinctions is the destruction of natural habitats by human activities, such as cutting down forests and converting land into fields for farming.[21]

Adagger symbol(†) placed next to the name of a species or other taxon normally indicates its status as extinct.

Examples

edit

Examples of species and subspecies that are extinct include:

Definition

edit
External mold of the extinctLepidodendronfrom theUpper CarboniferousofOhio[22][23]

A species is extinct when the last existing member dies. Extinction therefore becomes a certainty when there are no surviving individuals that can reproduce and create a new generation. A species may becomefunctionally extinctwhen only a handful of individuals survive, which cannot reproduce due to poor health, age, sparse distribution over a large range, a lack of individuals of both sexes (insexually reproducingspecies), or other reasons.

Pinpointing the extinction (orpseudoextinction) of a species requires aclear definition of that species.If it is to be declared extinct, the species in question must be uniquely distinguishable from any ancestor or daughter species, and from any other closely related species. Extinction of a species (or replacement by a daughter species) plays a key role in thepunctuated equilibriumhypothesis ofStephen Jay GouldandNiles Eldredge.[24]

Skeleton of various extinctdinosaurs;some other dinosaur lineages still flourish in the form ofbirds

Inecology,extinctionis sometimes used informally to refer tolocal extinction,in which a species ceases to exist in the chosen area of study, despite still existing elsewhere. Local extinctions may be made good by the reintroduction of individuals of that species taken from other locations;wolf reintroductionis an example of this. Species that are not globally extinct are termedextant.Those species that are extant, yet are threatened with extinction, are referred to asthreatenedorendangered species.

ThedodoofMauritius,shown here in a 1626 illustration byRoelant Savery,is an often-cited example ofmodern extinction.[25]

Currently, an important aspect of extinction is human attempts to preserve critically endangered species. These are reflected by the creation of theconservation status"extinct in the wild" (EW).Species listed under this status by theInternational Union for Conservation of Nature(IUCN) are not known to have any living specimens in the wild and are maintained only inzoosor other artificial environments. Some of these species are functionally extinct, as they are no longer part of their natural habitat and it is unlikely the species will ever be restored to the wild.[26]When possible, modernzoologicalinstitutions try to maintain aviable populationfor species preservation and possible futurereintroductionto the wild, through use of carefully plannedbreeding programs.

The extinction of one species' wild population can have knock-on effects, causing further extinctions. These are also called "chains of extinction".[27]This is especially common with extinction ofkeystone species.

A 2018 study indicated that thesixth mass extinctionstarted in theLate Pleistocenecould take up to 5 to 7 million years to restore mammal diversity to what it was before the human era.[16][28]

Pseudoextinction

edit

Extinction of a parent species where daughter species or subspecies are still extant is called pseudoextinction or phyletic extinction. Effectively, the old taxon vanishes, transformed (anagenesis) into a successor,[29]or split into more than one (cladogenesis).[30]

Pseudoextinction is difficult to demonstrate unless one has a strong chain of evidence linking a living species to members of a pre-existing species. For example, it is sometimes claimed that the extinctHyracotherium,which was an early horse that shares a common ancestor with the modernhorse,is pseudoextinct, rather than extinct, because there are several extant species ofEquus,includingzebraanddonkey;however, as fossil species typically leave no genetic material behind, one cannot say whetherHyracotheriumevolved into more modern horse speciesor merely evolved from a common ancestor with modern horses. Pseudoextinction is much easier to demonstrate for larger taxonomic groups.

Lazarus taxa

edit

A Lazarus taxon or Lazarus species refers to instances where a species or taxon was thought to be extinct, but was later rediscovered. It can also refer to instances where large gaps in the fossil record of a taxon result in fossils reappearing much later, although the taxon may have ultimately become extinct at a later point.

Thecoelacanth,a fish related tolungfishandtetrapods,is an example of a Lazarus taxon that was known only from the fossil record and was considered to have been extinct since the end of theCretaceous Period.In 1938, however, a living specimen was found off theChalumna River(now Tyolomnqa) on the east coast of South Africa.[31]Calliostoma bullatum,a species of deepwatersea snailoriginally described from fossils in 1844 proved to be a Lazarus species when extant individuals were described in 2019.[32]

Attenborough's long-beaked echidna(Zaglossus attenboroughi) is an example of a Lazarus species fromPapua New Guineathat had last been sighted in 1962 and believed to be possibly extinct, until it was recorded again in November 2023.[33]

Some species currently thought to be extinct have had continued speculation that they may still exist, and in the event of rediscovery would be considered Lazarus species. Examples include thethylacine,or Tasmanian tiger (Thylacinus cynocephalus), the last known example of which died in Hobart Zoo in Tasmania in 1936; theJapanese wolf(Canis lupus hodophilax), last sighted over 100 years ago; theAmerican ivory-billed woodpecker(Campephilus principalis), with the last universally accepted sighting in 1944; and theslender-billed curlew(Numenius tenuirostris), not seen since 2007.[34]

Causes

edit
Thepassenger pigeon,one of the hundreds of species of extinct birds, was hunted to extinction over the course of a few decades.

As long as species have been evolving, species have been going extinct. It is estimated that over 99.9% of all species that ever lived are extinct. The average lifespan of a species is 1–10 million years,[35]although this varies widely between taxa. A variety of causes can contribute directly or indirectly to the extinction of a species or group of species. "Just as each species is unique", write Beverly andStephen C. Stearns,"so is each extinction... the causes for each are varied—some subtle and complex, others obvious and simple".[36]Most simply, any species that cannotsurviveandreproducein its environment and cannot move to a new environment where it can do so, dies out and becomes extinct. Extinction of a species may come suddenly when an otherwise healthy species is wiped out completely, as whentoxicpollutionrenders its entirehabitatunliveable; or may occur gradually over thousands or millions of years, such as when a species gradually loses out in competition for food to better adapted competitors. Extinction may occur a long time after the events that set it in motion, a phenomenon known asextinction debt.

Assessing the relative importance of genetic factors compared to environmental ones as the causes of extinction has been compared to the debate onnature and nurture.[37]The question of whether more extinctions in thefossilrecord have been caused byevolutionor by competition or by predation or by disease or by catastrophe is a subject of discussion; Mark Newman, the author ofModeling Extinction,argues for a mathematical model that falls in all positions.[5]By contrast,conservation biologyuses theextinction vortexmodel to classify extinctions by cause. When concerns abouthuman extinctionhave been raised, for example in SirMartin Rees' 2003 bookOur Final Hour,those concerns lie with the effects ofclimate changeortechnologicaldisaster.

Human-driven extinction started as humans migrated out of Africa more than 60,000 years ago.[38]Currently, environmental groups and some governments are concerned with the extinction of species caused by humanity, and they try to prevent further extinctions through a variety ofconservationprograms.[10]Humans can cause extinction of a species throughoverharvesting,pollution,habitat destruction,introduction ofinvasive species(such as newpredatorsand foodcompetitors), overhunting, and other influences. Explosive, unsustainable humanpopulation growthandincreasing per capita consumptionare essential drivers of the extinction crisis.[39][40][41][42]According to theInternational Union for Conservation of Nature(IUCN), 784 extinctions have been recorded since the year 1500, the arbitrary date selected to define "recent" extinctions, up to the year 2004; with many more likely to have gone unnoticed. Several species have also been listed as extinct since 2004.[43]

Genetics and demographic phenomena

edit

Ifadaptationincreasing populationfitnessis slower thanenvironmental degradationplus the accumulation of slightly deleteriousmutations,then a population will go extinct.[44]Smaller populations have fewer beneficial mutations entering the population each generation, slowing adaptation. It is also easier for slightly deleterious mutations tofixin small populations; the resulting positive feedback loop between small population size and low fitness can causemutational meltdown.

Limited geographic range is the most important determinant ofgenusextinction at background rates but becomes increasingly irrelevant asmass extinctionarises.[45]Limited geographic range is a cause both of small population size and of greater vulnerability to local environmental catastrophes.

Extinction rates can be affected not just by population size, but by any factor that affectsevolvability,includingbalancing selection,cryptic genetic variation,phenotypic plasticity,androbustness.A diverse or deepgene poolgives a population a higher chance in the short term of surviving an adverse change in conditions. Effects that cause or reward a loss ingenetic diversitycan increase the chances of extinction of a species.Population bottleneckscan dramatically reduce genetic diversity by severely limiting the number of reproducing individuals and makeinbreedingmore frequent.

Genetic pollution

edit

Extinction sometimes results for species evolved to specific ecologies[46]that are subjected togenetic pollution—i.e., uncontrolledhybridization,introgressionand genetic swamping that lead to homogenization orout-competitionfrom the introduced (or hybrid) species.[47]Endemic populations can face such extinctions when new populations are imported orselectively bredby people, or when habitat modification brings previously isolated species into contact. Extinction is likeliest forrare speciescoming into contact with more abundant ones;[48]interbreedingcan swamp the rarer gene pool and create hybrids, depleting the purebred gene pool (for example, the endangeredwild water buffalois most threatened with extinction by genetic pollution fromthe abundant domestic water buffalo). Such extinctions are not always apparent frommorphological(non-genetic) observations. Some degree ofgene flowis a normal evolutionary process; nevertheless, hybridization (with or without introgression) threatens rare species' existence.[49][50]

The gene pool of aspeciesor apopulationis the variety of genetic information in its living members. A large gene pool (extensivegenetic diversity) is associated with robust populations that can survive bouts of intenseselection.Meanwhile, low genetic diversity (seeinbreedingandpopulation bottlenecks) reduces the range of adaptions possible.[51]Replacing native with alien genes narrows genetic diversity within the original population,[48][52]thereby increasing the chance of extinction.

Habitat degradation

edit
Scorched land resulting fromslash-and-burnagriculture

Habitat degradation is currently the main anthropogenic cause of species extinctions. The main cause of habitat degradation worldwide is agriculture, withurban sprawl,logging, mining, and some fishing practices close behind. The degradation of a species'habitatmay alter thefitness landscapeto such an extent that the species is no longer able to survive and becomes extinct. This may occur by direct effects, such as the environment becomingtoxic,or indirectly, by limiting a species' ability to compete effectively for diminished resources or against new competitor species.

Habitat destruction, particularly the removal of vegetation that stabilizes soil, enhances erosion and diminishes nutrient availability in terrestrial ecosystems. This degradation can lead to a reduction in agricultural productivity. Furthermore, increased erosion contributes to poorer water quality by elevating the levels of sediment and pollutants in rivers and streams.[53]

Habitat degradation through toxicity can kill off a species very rapidly, by killing all living members throughcontaminationorsterilizingthem. It can also occur over longer periods at lower toxicity levels by affecting life span, reproductive capacity, or competitiveness.

Habitat degradation can also take the form of a physical destruction of niche habitats. The widespread destruction oftropical rainforestsand replacement with open pastureland is widely cited as an example of this;[15]elimination of the dense forest eliminated the infrastructure needed by many species to survive. For example, afernthat depends on dense shade for protection from direct sunlight can no longer survive without forest to shelter it. Another example is the destruction of ocean floors bybottom trawling.[54]

Diminished resources or introduction of new competitor species also often accompany habitat degradation.Global warminghas allowed some species to expand their range, bringing competition to other species that previously occupied that area. Sometimes these new competitors are predators and directly affect prey species, while at other times they may merely outcompete vulnerable species for limited resources. Vital resources includingwaterand food can also be limited during habitat degradation, leading to extinction.

Predation, competition, and disease

edit
Thegolden toadwas last seen on May 15, 1989.Decline in amphibian populationsis ongoing worldwide.

In the natural course of events, species become extinct for a number of reasons, including but not limited to: extinction of a necessary host, prey or pollinator,interspecific competition,inability to deal with evolving diseases and changing environmental conditions (particularly sudden changes) which can act to introduce novel predators, or to remove prey. Recently in geological time, humans have become an additional cause of extinction of some species, either as a new mega-predator or bytransportinganimalsandplantsfrom one part of the world to another. Such introductions have been occurring for thousands of years, sometimes intentionally (e.g.livestockreleased by sailors on islands as a future source of food) and sometimes accidentally (e.g.ratsescaping from boats). In most cases, the introductions are unsuccessful, but when aninvasive alien speciesdoes become established, the consequences can be catastrophic. Invasive alien species can affectnativespecies directly by eating them, competing with them, and introducingpathogensorparasitesthat sicken or kill them; or indirectly by destroying or degrading their habitat. Human populations may themselves act as invasive predators. According to the "overkill hypothesis", the swift extinction of themegafaunain areas such as Australia (40,000 years before present),NorthandSouth America(12,000 years before present),Madagascar,Hawaii(AD 300–1000), and New Zealand (AD 1300–1500), resulted from the sudden introduction of human beings to environments full of animals that had never seen them before and were therefore completely unadapted to their predation techniques.[55]

Coextinction

edit
The largeHaast's eagleandmoafrom New Zealand

Coextinction refers to the loss of a species due to the extinction of another; for example, the extinction ofparasiticinsects following the loss of their hosts. Coextinction can also occur when a species loses itspollinator,or topredatorsin afood chainwho lose their prey. "Species coextinction is a manifestation of one of the interconnectednesses of organisms in complex ecosystems... While coextinction may not be the most important cause of species extinctions, it is certainly an insidious one."[56]Coextinction is especially common when akeystone speciesgoes extinct. Models suggest that coextinction is the most common form ofbiodiversity loss.There may be a cascade of coextinction across thetrophic levels.Such effects are most severe inmutualisticand parasitic relationships. An example of coextinction is theHaast's eagleand themoa:the Haast's eagle was a predator that became extinct because its food source became extinct. The moa were several species of flightless birds that were a food source for the Haast's eagle.[57]

Climate change

edit

Extinction as a result ofclimate changehas been confirmed by fossil studies.[58]Particularly, the extinction of amphibians during theCarboniferous Rainforest Collapse,305 million years ago.[58]A 2003 review across 14 biodiversity research centers predicted that, because of climate change, 15–37% of land species would be "committed to extinction" by 2050.[59][60]The ecologically rich areas that would potentially suffer the heaviest losses include theCape Floristic Regionand theCaribbean Basin.These areas might see a doubling of present carbon dioxide levels and rising temperatures that could eliminate 56,000 plant and 3,700 animal species.[61]Climate change has also been found to be a factor inhabitat lossanddesertification.[62]

Sexual selection and male investment

edit

Studies of fossils following species from the time they evolved to their extinction show that species with highsexual dimorphism,especially characteristics in males that are used to compete for mating, are at a higher risk of extinction and die out faster than less sexually dimorphic species, the least sexually dimorphic species surviving for millions of years while the most sexually dimorphic species die out within mere thousands of years. Earlier studies based on counting the number of currently living species in modern taxa have shown a higher number of species in more sexually dimorphic taxa which have been interpreted as higher survival in taxa with more sexual selection, but such studies of modern species only measure indirect effects of extinction and are subject to error sources such as dying and doomed taxa speciating more due to splitting of habitat ranges into more small isolated groups during the habitat retreat of taxa approaching extinction. Possible causes of the higher extinction risk in species with more sexual selection shown by the comprehensive fossil studies that rule out such error sources include expensive sexually selected ornaments having negative effects on the ability to survivenatural selection,as well assexual selectionremoving a diversity of genes that under current ecological conditions are neutral for natural selection but some of which may be important for surviving climate change.[63]

Mass extinctions

edit
CambrianOrdovicianSilurianDevonianCarboniferousPermianTriassicJurassicCretaceousPaleogeneNeogene
Marine extinction intensity duringPhanerozoic
%
Millions of years ago
CambrianOrdovicianSilurianDevonianCarboniferousPermianTriassicJurassicCretaceousPaleogeneNeogene
The blue graph shows the apparentpercentage(not the absolute number) of marineanimalgenerabecoming extinct during any given time interval. It does not represent all marine species, just those that are readily fossilized. The labels of the traditional "Big Five" extinction events and the more recently recognisedCapitanian mass extinction eventare clickable links; seeExtinction eventfor more details.(source and image info)

There have been at least five mass extinctions in the history of life on earth, and four in the last 350 million years in which many species have disappeared in a relatively short period of geological time. A massive eruptive event that released large quantities oftephraparticles into the atmosphere is considered to be one likely cause of the "Permian–Triassic extinction event"about 250 million years ago,[64]which is estimated to have killed 90% of species then existing.[65]There is also evidence to suggest that this event was preceded by another mass extinction, known asOlson's Extinction.[64]TheCretaceous–Paleogene extinction event(K–Pg) occurred 66 million years ago, at the end of theCretaceousperiod; it is best known for having wiped out non-aviandinosaurs,among many other species.

Modern extinctions

edit
The changing distribution of the world's land mammals in tonnes of carbon. Thebiomassof wild land mammals has declined by 85% since the emergence of humans.[66]

According to a 1998 survey of 400 biologists conducted byNew York'sAmerican Museum of Natural History,nearly 70% believed that the Earth is currently in the early stages of a human-caused mass extinction,[67]known as theHolocene extinction.In that survey, the same proportion of respondents agreed with the prediction that up to 20% of all living populations could become extinct within 30 years (by 2028). A 2014 special edition ofSciencedeclared there is widespread consensus on the issue of human-driven mass species extinctions.[68]A 2020 study published inPNASstated that the contemporary extinction crisis "may be the most serious environmental threat to the persistence of civilization, because it is irreversible."[69]

BiologistE. O. Wilsonestimated[15]in 2002 that if current rates of human destruction of the biosphere continue, one-half of all plant and animal species of life on earth will be extinct in 100 years.[70]More significantly, the current rate of global species extinctions is estimated as 100 to 1,000 times "background" rates (the average extinction rates in theevolutionarytime scale of planet Earth),[71][72]faster than at any other time in human history,[73][74]while future rates are likely 10,000 times higher.[72]However, some groups are going extinct much faster. BiologistsPaul R. EhrlichandStuart Pimm,among others, contend thathuman population growthandoverconsumptionare the main drivers of the modern extinction crisis.[75][76][39][77]

In January 2020, the UN'sConvention on Biological Diversitydrafted a plan to mitigate the contemporary extinction crisis by establishing a deadline of 2030 to protect 30% of the Earth's land and oceans and reduce pollution by 50%, with the goal of allowing for the restoration of ecosystems by 2050.[78][79]The 2020United Nations'Global Biodiversity Outlookreport stated that of the 20 biodiversity goals laid out by the Aichi Biodiversity Targets in 2010, only 6 were "partially achieved" by the deadline of 2020.[80]The report warned that biodiversity will continue to decline if the status quo is not changed, in particular the "currently unsustainable patterns of production and consumption, population growth and technological developments".[81]In a 2021 report published in the journalFrontiers in Conservation Science,some top scientists asserted that even if the Aichi Biodiversity Targets set for 2020 had been achieved, it would not have resulted in a significant mitigation of biodiversity loss. They added that failure of the global community to reach these targets is hardly surprising given that biodiversity loss is "nowhere close to the top of any country's priorities, trailing far behind other concerns such as employment, healthcare, economic growth, or currency stability."[82][83]

History of scientific understanding

edit
Tyrannosaurus,one of the many extinct dinosaur genera. The cause of theCretaceous–Paleogene extinction eventis a subject of much debate amongst researchers.
Georges Cuvier's 1812 unpublished version of the skeletal reconstruction ofAnoplotheriumcommunewith muscles. Today, thePaleogenemammal is thought to have gone extinct from theGrande Coupureextinction event in western Europe.[84]
Georges Cuviercompared fossilmammothjaws to those of living elephants, concluding that they were distinct from any known living species.[85]

For much of history, the modern understanding of extinction as the end of aspecieswas incompatible with the prevailing worldview. Prior to the 19th century, much of Western society adhered to the belief that the world was created by God and as such was complete and perfect.[86]This concept reached its heyday in the 1700s with the peak popularity of a theological concept called thegreat chain of being,in which all life on earth, from the tiniest microorganism to God, is linked in a continuous chain.[87]The extinction of a species was impossible under this model, as it would create gaps or missing links in the chain and destroy the natural order.[86][87]Thomas Jeffersonwas a firm supporter of the great chain of being and an opponent of extinction,[86][88]famously denying the extinction of thewoolly mammothon the grounds that nature never allows a race of animals to become extinct.[89]

A series of fossils were discovered in the late 17th century that appeared unlike any living species. As a result, the scientific community embarked on a voyage of creative rationalization, seeking to understand what had happened to these species within a framework that did not account for total extinction. In October 1686,Robert Hookepresented an impression of anautilusto theRoyal Societythat was more than two feet in diameter,[90]and morphologically distinct from any known living species.Hooketheorized that this was simply because the species lived in the deep ocean and no one had discovered them yet.[87]While he contended that it was possible a species could be "lost", he thought this highly unlikely.[87]Similarly, in 1695,Sir Thomas Molyneuxpublished an account of enormous antlers found inIrelandthat did not belong to any extant taxa in that area.[88][91]Molyneux reasoned that they came from the North Americanmooseand that the animal had once been common on theBritish Isles.[88][91]Rather than suggest that this indicated the possibility of species going extinct, he argued that although organisms could become locally extinct, they could never be entirely lost and would continue to exist in some unknown region of the globe.[91]The antlers were later confirmed to be from the extinctdeerMegaloceros.[88]Hooke and Molyneux's line of thinking was difficult to disprove. When parts of the world had not been thoroughly examined and charted, scientists could not rule out that animals found only in the fossil record were not simply "hiding" in unexplored regions of the Earth.[92]

Georges Cuvieris credited with establishing the modern conception of extinction in a 1796 lecture to theFrench Institute,[85][89]though he would spend most of his career trying to convince the wider scientific community of his theory.[93]Cuvier was a well-regarded geologist, lauded for his ability to reconstruct the anatomy of an unknown species from a few fragments of bone.[85]His primary evidence for extinction came from mammoth skulls found in theParis basin.[85]Cuvier recognized them as distinct from any known living species of elephant, and argued that it was highly unlikely such an enormous animal would go undiscovered.[85]In 1812, Cuvier, along withAlexandre BrongniartandGeoffroy Saint-Hilaire,mapped thestrataof the Paris basin.[87]They saw alternating saltwater and freshwater deposits, as well as patterns of the appearance and disappearance of fossils throughout the record.[88][93]From these patterns, Cuvier inferred historic cycles of catastrophic flooding, extinction, and repopulation of the earth with new species.[88][93]

Cuvier's fossil evidence showed that very different life forms existed in the past than those that exist today, a fact that was accepted by most scientists.[86]The primary debate focused on whether this turnover caused by extinction was gradual or abrupt in nature.[93]Cuvier understood extinction to be the result of cataclysmic events that wipe out huge numbers of species, as opposed to the gradual decline of a species over time.[94]His catastrophic view of the nature of extinction garnered him many opponents in the newly emerging school ofuniformitarianism.[94]

Jean-Baptiste Lamarck,agradualistand colleague of Cuvier, saw the fossils of different life forms as evidence of the mutable character of species.[93]While Lamarck did not deny the possibility of extinction, he believed that it was exceptional and rare and that most of the change in species over time was due to gradual change.[93]Unlike Cuvier, Lamarck was skeptical that catastrophic events of a scale large enough to cause total extinction were possible. In his geological history of the earth titled Hydrogeologie, Lamarck instead argued that the surface of the earth was shaped by gradual erosion and deposition by water, and that species changed over time in response to the changing environment.[93][95]

Charles Lyell,a noted geologist and founder ofuniformitarianism,believed that past processes should be understood using present day processes. Like Lamarck, Lyell acknowledged that extinction could occur, noting the total extinction of thedodoand the extirpation ofindigenous horsesto the British Isles.[87]He similarly argued againstmass extinctions,believing that any extinction must be a gradual process.[85][89]Lyell also showed that Cuvier's original interpretation of the Parisian strata was incorrect. Instead of the catastrophic floods inferred by Cuvier, Lyell demonstrated that patterns of saltwater and freshwaterdeposits,like those seen in the Paris basin, could be formed by a slow rise and fall ofsea levels.[88]

The concept of extinction was integral toCharles Darwin'sOn the Origin of Species,with less fit lineages disappearing over time. For Darwin, extinction was a constant side effect ofcompetition.[96]Because of the wide reach ofOn the Origin of Species,it was widely accepted that extinction occurred gradually and evenly (a concept now referred to asbackground extinction).[89]It was not until 1982, whenDavid RaupandJack Sepkoskipublished their seminal paper on mass extinctions, that Cuvier was vindicated and catastrophic extinction was accepted as an important mechanism[citation needed].The current understanding of extinction is a synthesis of the cataclysmic extinction events proposed by Cuvier, and the background extinction events proposed by Lyell and Darwin.

Human attitudes and interests

edit
Agreat hammerheadcaught by a sport fisherman. Human exploitation now threatens the survival of this species.Overfishingis the primary driver of shark population declines, which have fallen over 71% since 1970.[97][98]

Extinction is an important research topic in the field ofzoology,andbiologyin general, and has also become an area of concern outside the scientific community. A number of organizations, such as theWorldwide Fund for Nature,have been created with the goal of preserving species from extinction.Governmentshave attempted, through enacting laws, to avoid habitat destruction, agricultural over-harvesting, andpollution.While many human-caused extinctions have been accidental, humans have also engaged in the deliberate destruction of some species, such as dangerousviruses,and the total destruction of other problematic species has been suggested. Other species were deliberately driven to extinction, or nearly so, due topoachingor because they were "undesirable", or to push for other human agendas. One example was the near extinction of theAmerican bison,which was nearly wiped out by mass hunts sanctioned by the United States government, to force the removal ofNative Americans,many of whom relied on the bison for food.[99]

BiologistBruce Walshstates three reasons for scientific interest in the preservation of species:genetic resources,ecosystem stability, andethics;and today the scientific community "stress[es] the importance" of maintaining biodiversity.[100][101]

In modern times, commercial and industrial interests often have to contend with the effects of production on plant and animal life. However, some technologies with minimal, or no, proven harmful effects onHomo sapienscan be devastating to wildlife (for example,DDT).[102][103]BiogeographerJared Diamondnotes that whilebig businessmay label environmental concerns as "exaggerated", and often cause "devastating damage", some corporations find it in their interest to adopt good conservation practices, and even engage in preservation efforts that surpass those taken bynational parks.[104]

Governments sometimes see the loss of native species as a loss toecotourism,[105]and can enact laws with severe punishment against the trade in native species in an effort to prevent extinction in the wild.Nature preservesare created by governments as a means to provide continuing habitats to species crowded by human expansion. The 1992Convention on Biological Diversityhas resulted in internationalBiodiversity Action Planprogrammes, which attempt to provide comprehensive guidelines for government biodiversity conservation. Advocacy groups, such as The Wildlands Project[106]and the Alliance for Zero Extinctions,[107]work to educate the public and pressure governments into action.

People who live close to nature can be dependent on the survival of all the species in their environment, leaving them highly exposed to extinctionrisks.However, people prioritize day-to-day survival over species conservation; withhuman overpopulationin tropicaldeveloping countries,there has been enormous pressure on forests due tosubsistence agriculture,includingslash-and-burnagricultural techniques that can reduce endangered species's habitats.[108]

AntinatalistphilosopherDavid Benatarconcludes that any popular concern about non-human species extinction usually arises out of concern about how the loss of a species will impact human wants and needs, that "we shall live in a world impoverished by the loss of one aspect of faunal diversity, that we shall no longer be able to behold or use that species of animal." He notes that typical concerns about possible human extinction, such as the loss of individual members, are not considered in regards to non-human species extinction.[109]AnthropologistJason Hickelspeculates that the reason humanity seems largely indifferent to anthropogenic mass species extinction is that we see ourselves as separate from the natural world and the organisms within it. He says that this is due in part to the logic ofcapitalism:"that the world is not really alive, and it is certainly not our kin, but rather just stuff to be extracted and discarded – and that includes most of the human beings living here too."[110]

Planned extinction

edit

Completed

edit

Proposed

edit
Disease agents
edit

Thepoliovirusis now confined to small parts of the world due to extermination efforts.[113]

Dracunculus medinensis,or Guinea worm, a parasitic worm which causes the diseasedracunculiasis,is now close to eradication thanks to efforts led by theCarter Center.[114]

Treponema pallidum pertenue,a bacterium which causes the diseaseyaws,is in the process of being eradicated.

Disease vectors
edit

BiologistOlivia Judsonhas advocated the deliberate extinction of certain disease-carryingmosquitospecies. In a September 25, 2003 article inThe New York Times,she advocated "specicide" of thirty mosquito species by introducing a genetic element that can insert itself into another crucial gene, to createrecessive"knockout genes".[115]She says that theAnophelesmosquitoes (which spreadmalaria) andAedesmosquitoes (which spreaddengue fever,yellow fever,elephantiasis,and other diseases) represent only 30 of around 3,500 mosquito species; eradicating these would save at least one million human lives per year, at a cost of reducing thegenetic diversityof the familyCulicidaeby only 1%. She further argues that since species become extinct "all the time" the disappearance of a few more will not destroy theecosystem:"We're not left with a wasteland every time a species vanishes. Removing one species sometimes causes shifts in the populations of other species—but different need not mean worse." In addition, anti-malarial andmosquito control programsoffer little realistic hope to the 300 million people indeveloping nationswho will be infected with acute illnesses this year. Although trials are ongoing, she writes that if they fail "we should consider the ultimate swatting."[115]

BiologistE. O. Wilsonhas advocated the eradication of several species of mosquito, including malaria vectorAnopheles gambiae.Wilson stated, "I'm talking about a very small number of species that have co-evolved with us and are preying on humans, so it would certainly be acceptable to remove them. I believe it's just common sense."[116]

There have been many campaigns – some successful – to locally eradicatetsetse fliesand theirtrypanosomesin areas, countries, and islands of Africa (includingPríncipe).[117][118]There are currently serious efforts to do away with them all across Africa, and this is generally viewed as beneficial and morally necessary,[119]although not always.[120]

Cloning

edit
ThePyrenean ibex,the only animal to have been brought back from extinction and the only one to go extinct twice.

Some, such as Harvard geneticistGeorge M. Church,believe that ongoing technological advances will let us "bring back to life" an extinct species bycloning,usingDNAfrom the remains of that species. Proposed targets for cloning include themammoth,thethylacine,and thePyrenean ibex.For this to succeed, enough individuals would have to be cloned, from the DNA of different individuals (in the case of sexually reproducing organisms) to create a viable population. Thoughbioethicalandphilosophicalobjections have been raised,[121]the cloning of extinct creatures seems theoretically possible.[122]

In 2003, scientists tried to clone the extinct Pyrenean ibex (C. p. pyrenaica).[123]This attempt failed: of the 285 embryos reconstructed, 54 were transferred to 12Spanish ibexesand ibex–domesticgoathybrids, but only two survived the initial two months of gestation before they, too, died.[124]In 2009, a second attempt was made to clone the Pyrenean ibex: one clone was born alive, but died seven minutes later, due to physical defects in the lungs.[125]

See also

edit

References

edit
  1. ^McKinney, Michael L. (1997)."How do rare species avoid extinction? A paleontological view".In Kunin, W. E.; Gaston, K. J. (eds.).The Biology of Rarity.pp. 110–129.doi:10.1007/978-94-011-5874-9_7.ISBN978-94-010-6483-5.Archivedfrom the original on 3 February 2023.Retrieved26 May2015.
  2. ^Jablonski, D. (2004)."Extinction: past and present".Nature.427(6975): 589.Bibcode:2004Natur.427..589J.doi:10.1038/427589a.PMID14961099.S2CID4412106.
  3. ^Stearns, Beverly Peterson; Stearns, S.C.; Stearns, Stephen C. (2000).Watching, from the Edge of Extinction.Yale University Press.p. preface x.ISBN978-0-300-08469-6.Archivedfrom the original on 3 February 2023.Retrieved30 May2017.
  4. ^Novacek, Michael J.(8 November 2014)."Prehistory's Brilliant Future".The New York Times.Archivedfrom the original on 29 December 2014.Retrieved25 December2014.
  5. ^abcNewman, Mark (1997). "A model of mass extinction".Journal of Theoretical Biology.189(3): 235–252.arXiv:adap-org/9702003.Bibcode:1997JThBi.189..235N.doi:10.1006/jtbi.1997.0508.PMID9441817.S2CID9892809.
  6. ^Mora, Camilo; Tittensor, Derek P.; Adl, Sina; Simpson, Alastair G. B.; Worm, Boris (2011)."How Many Species Are There on Earth and in the Ocean?".PLOS Biology.9(8): e1001127.doi:10.1371/journal.pbio.1001127.PMC3160336.PMID21886479.
  7. ^"Researchers find that Earth may be home to 1 trillion species".National Science Foundation.2 May 2016.Archivedfrom the original on 4 May 2016.Retrieved6 May2016.
  8. ^Sahney, S.; Benton, M.J.; Ferry, P.A. (2010)."Links between global taxonomic diversity, ecological diversity and the expansion of vertebrates on land".Biology Letters.6(4): 544–547.doi:10.1098/rsbl.2009.1024.PMC2936204.PMID20106856.
  9. ^Sudakow, Ivan; Myers, Corinne; Petrovskii, Sergei; Sumrall, Colin D.; Witts, James (July 2022)."Knowledge gaps and missing links in understanding mass extinctions: Can mathematical modeling help?".Physics of Life Reviews.41:22–57.Bibcode:2022PhLRv..41...22S.doi:10.1016/j.plrev.2022.04.001.PMID35523056.S2CID248215038.
  10. ^ab"Species disappearing at an alarming rate, report says".NBC News.17 November 2004.Archivedfrom the original on 9 February 2022.Retrieved9 February2022.
  11. ^The Sixth ExtinctiononYouTube(PBS Digital Studios,November 17, 2014)
  12. ^Ceballos, Gerardo; Ehrlich, Paul R.;Barnosky, Anthony D.;García, Andrés; Pringle, Robert M.; Palmer, Todd M. (2015)."Accelerated modern human–induced species losses: Entering the sixth mass extinction".Science Advances.1(5): e1400253.Bibcode:2015SciA....1E0253C.doi:10.1126/sciadv.1400253.PMC4640606.PMID26601195.
  13. ^Ripple WJ, Wolf C, Newsome TM, Galetti M, Alamgir M, Crist E, Mahmoud MI, Laurance WF (13 November 2017)."World Scientists' Warning to Humanity: A Second Notice".BioScience.67(12): 1026–1028.doi:10.1093/biosci/bix125.hdl:11336/71342.Moreover, we have unleashed a mass extinction event, the sixth in roughly 540 million years, wherein many current life forms could be annihilated or at least committed to extinction by the end of this century.
  14. ^Cowie, Robert H.; Bouchet, Philippe; Fontaine, Benoît (10 January 2022)."The Sixth Mass Extinction: fact, fiction or speculation?".Biological Reviews.97(2): 640–663.doi:10.1111/brv.12816.PMC9786292.PMID35014169.S2CID245889833.Archivedfrom the original on 9 February 2022.Retrieved9 February2022.
  15. ^abcWilson, E.O.,The Future of Life(2002) (ISBN0-679-76811-4). See also:Leakey, Richard,The Sixth Extinction: Patterns of Life and the Future of Humankind,ISBN0-385-46809-1
  16. ^abDavis M, Faurby S, Svenning JC (2018)."Mammal diversity will take millions of years to recover from the current biodiversity crisis".Proc Natl Acad Sci U S A.115(44): 11262–11267.Bibcode:2018PNAS..11511262D.doi:10.1073/pnas.1804906115.PMC6217385.PMID30322924.
  17. ^Watts, Jonathan (6 May 2019)."Human society under urgent threat from loss of Earth's natural life".The Guardian.Archivedfrom the original on 14 June 2019.Retrieved6 May2019.
  18. ^Plumer, Brad (6 May 2019)."Humans Are Speeding Extinction and Altering the Natural World at an 'Unprecedented' Pace".The New York Times.Archivedfrom the original on 14 June 2019.Retrieved6 May2019.
  19. ^"Media Release: Nature's Dangerous Decline 'Unprecedented'; Species Extinction Rates 'Accelerating'".Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services.6 May 2019.Archivedfrom the original on 14 June 2019.Retrieved6 May2019.
  20. ^Briggs, Helen (8 July 2022)."Unsustainable logging, fishing and hunting 'driving extinction'".BBC.Archivedfrom the original on 1 August 2022.Retrieved2 August2022.
  21. ^"'Frightening' number of plant extinctions found in global survey ".The Guardian.10 June 2019.Archivedfrom the original on 22 April 2021.Retrieved11 June2019.
  22. ^Kenrick, Paul; Davis, Paul (2004).Fossil Plants.Smithsonian Books.ISBN978-0-565-09176-7.[page needed]
  23. ^Moran, Robbin Craig (2004).A Natural History of Ferns.Timber Press.ISBN978-0-88192-667-5.[page needed]
  24. ^See: Niles Eldredge,Time Frames: Rethinking of Darwinian Evolution and the Theory of Punctuated Equilibria,1986, HeinemannISBN0-434-22610-6
  25. ^Diamond, Jared(1999). "Up to the Starting Line".Guns, Germs, and Steel.W.W. Norton. pp.43–44.ISBN978-0-393-31755-8.
  26. ^Maas, Peter. "Extinct in the Wild "The Extinction Website.URL accessed January 26 2007.ArchivedFebruary 16, 2007, at theWayback Machine
  27. ^Quince, Christopher; Higgs, Paul G.; McKane, Alan J. (August 2005). "Deleting species from model food webs".Oikos.110(2): 283–296.arXiv:q-bio/0401037.Bibcode:2005Oikos.110..283Q.doi:10.1111/j.0030-1299.2005.13493.x.S2CID16750824.
  28. ^Mosbergen, Dominique (16 October 2018)."Mammals Will Still Be Recovering From Human Destruction Long After We're Gone".HuffPost.Archivedfrom the original on 9 February 2022.Retrieved9 February2022.
  29. ^King, Michael; Mulligan, Pamela; Stansfield, William (2014). "Pseudoextinction".A Dictionary of Genetics(8th ed.). Oxford University Press.ISBN978-0-19-976644-4.Archivedfrom the original on 21 March 2024.Retrieved12 November2023.
  30. ^Leighton, Lindsey R. (2009). "Taxon Characteristics That Promote Survivorship Through the Permian-Triassic Interval: Transition from the Paleozoic to the Mesozoic Brachiopod Fauna".Paleobiology.34:65–79.doi:10.1666/06082.1.S2CID86843206.
  31. ^""Discovery" of the Coelacanth ".Archivedfrom the original on 21 January 2013.Retrieved2 March2013.
  32. ^Freiwald, André; Lavaleye, Marc; Heugten, Bart Van; Beuck, Lydia; Hoffman, Leon (4 June 2019)."Last snails standing since the Early Pleistocene, a tale of Calliostomatidae (Gastropoda) living in deep-water coral habitats in the north-eastern Atlantic".Zootaxa.4613(1): 93–110.doi:10.11646/zootaxa.4613.1.4.ISSN1175-5334.PMID31716426.
  33. ^"First-ever images prove 'lost echidna' not extinct".10 November 2023.Retrieved25 November2023.
  34. ^Platt, John R. (21 February 2013)."4 Extinct Species That People Still Hope to Rediscover".Scientific American Blog Network.Archivedfrom the original on 9 February 2022.Retrieved9 February2022.[self-published source?]
  35. ^Mills, L. Scott (2009).Conservation of Wildlife Populations: Demography, Genetics and Management.John Wiley & Sons. p. 13.ISBN978-1-4443-0893-8.
  36. ^Stearns, Beverly Peterson and Stephen C. (2000). "Preface".Watching, from the Edge of Extinction.Yale University Press. pp. x.ISBN978-0-300-08469-6.
  37. ^Raup, David M.; J. John Sepkoski Jr. (March 1982). "Mass extinctions in the marine fossil record".Science.215(4539): 1501–1503.Bibcode:1982Sci...215.1501R.doi:10.1126/science.215.4539.1501.PMID17788674.S2CID43002817.
  38. ^Johns, David; Crist, Eileen; Sahgal, Bittu, eds. (2022)."Ending the Colonization of the Non-Human World".Biological Conservation.Archivedfrom the original on 18 November 2022.
  39. ^abCeballos, Gerardo; Ehrlich, Paul R; Dirzo, Rodolfo (23 May 2017)."Biological annihilation via the ongoing sixth mass extinction signaled by vertebrate population losses and declines".PNAS.114(30): E6089–E6096.Bibcode:2017PNAS..114E6089C.doi:10.1073/pnas.1704949114.PMC5544311.PMID28696295.Much less frequently mentioned are, however, the ultimate drivers of those immediate causes of biotic destruction, namely, human overpopulation and continued population growth, and overconsumption, especially by the rich. These drivers, all of which trace to the fiction that perpetual growth can occur on a finite planet, are themselves increasing rapidly.
  40. ^Stokstad, Erik (6 May 2019). "Landmark analysis documents the alarming global decline of nature".Science.doi:10.1126/science.aax9287.S2CID166478506.
  41. ^Andermann, Tobias; Faurby, Søren; Turvey, Samuel T.; Antonelli, Alexandre; Silvestro, Daniele (1 September 2020)."The past and future human impact on mammalian diversity".Science Advances.6(36): eabb2313.Bibcode:2020SciA....6.2313A.doi:10.1126/sciadv.abb2313.PMC7473673.PMID32917612.S2CID221498762.Text and images are available under aCreative Commons Attribution 4.0 International LicenseArchived16 October 2017 at theWayback Machine.
  42. ^Lewis, Sophie (9 September 2020)."Animal populations worldwide have declined by almost 70% in just 50 years, new report says".CBS News.Archivedfrom the original on 10 September 2020.Retrieved22 October2020.
  43. ^"2004 Red List".IUCN Red List of Threatened Species.World Conservation Union.Archived fromthe originalon 27 August 2006.Retrieved20 September2006.
  44. ^Bertram, J; Gomez, K; Masel, J (February 2017). "Predicting patterns of long-term adaptation and extinction with population genetics".Evolution.71(2): 204–214.arXiv:1605.08717.doi:10.1111/evo.13116.PMID27868195.S2CID4705439.
  45. ^Payne, J.L.; S. Finnegan (2007)."The effect of geographic range on extinction risk during background and mass extinction".Proc. Natl. Acad. Sci.104(25): 10506–10511.Bibcode:2007PNAS..10410506P.doi:10.1073/pnas.0701257104.PMC1890565.PMID17563357.
  46. ^Mooney, H.A.; Cleland, E.E. (2001)."The evolutionary impact of invasive species".PNAS.98(10): 5446–5451.Bibcode:2001PNAS...98.5446M.doi:10.1073/pnas.091093398.PMC33232.PMID11344292.
  47. ^"Glossary: definitions from the following publication: Aubry, C., R. Shoal and V. Erickson. 2005. Grass cultivars: their origins, development, and use on national forests and grasslands in the Pacific Northwest. USDA Forest Service. 44 pages, plus appendices.; Native Seed Network (NSN), Institute for Applied Ecology, 563 SW Jefferson Ave, Corvallis, OR 97333, USA".Archived fromthe originalon 22 February 2006.
  48. ^ab "Australia's state of the forests report"(PDF).2003. p. 107. Archived fromthe original(PDF)on 13 March 2011.
  49. ^Rhymer, J.M.; Simberloff, D. (November 1996). "Extinction by Hybridization and Introgression".Annual Review of Ecology and Systematics.27.Annual Reviews: 83–109.doi:10.1146/annurev.ecolsys.27.1.83.JSTOR2097230.Introduced species, in turn, are seen as competing with or preying on native species or destroying their habitat. Introduces species (orsubspecies), however, can generate another kind of extinction, a genetic extinction by hybridization and introgression with native flora and fauna
  50. ^Potts, Brad M. (September 2001).Genetic pollution from farm forestry using eucalypt species and hybrids: a report for the RIRDC/L&WA/FWPRDC Joint Venture Agroforestry Program.Robert C. Barbour, Andrew B. Hingston. Australian Government, Rural Industrial Research and Development Corporation.ISBN978-0-642-58336-9.
  51. ^ "Genetic diversity"(PDF).2003. p. 104. Archived fromthe original(PDF)on 13 March 2011.Retrieved30 May2010.In other words, greater genetic diversity can offer greater resilience. In order to maintain the capacity of our forests toadaptto future changes, therefore, genetic diversity must be preserved
  52. ^Lindenmayer, D. B.; Hobbs, R. J.; Salt, D. (January 2003)."Plantation forests and biodiversity conservation"(PDF).Australian Forestry.66(1): 62–66.Bibcode:2003AuFor..66...62L.doi:10.1080/00049158.2003.10674891.S2CID53968395.Archived(PDF)from the original on 17 February 2022.Retrieved9 February2022.
  53. ^"Habitat loss / restoration".Understanding Global Change.Retrieved12 April2024.
  54. ^Clover, Charles (2004).The End of the Line: How overfishing is changing the world and what we eat.London: Ebury Press.ISBN978-0-09-189780-2.
  55. ^Lee, Anita. "The Pleistocene Overkill HypothesisArchivedOctober 14, 2006, at theWayback Machine."University of California at Berkeley Geography Program.Retrieved January 11, 2007.
  56. ^Koh, Lian Pin; Dunn, Robert R.; Sodhi, Navjot S.; Colwell, Robert K.; Proctor, Heather C.; Smith, Vincent S. (10 September 2004). "Species Coextinctions and the Biodiversity Crisis".Science.305(5690): 1632–1634.Bibcode:2004Sci...305.1632K.doi:10.1126/science.1101101.PMID15361627.S2CID30713492.
  57. ^Dunn, Robert R.; Harris, Nyeema C.; Colwell, Robert K.; Koh, Lian Pin; Sodhi, Navjot S. (7 September 2009)."The sixth mass coextinction: are most endangered species parasites and mutualists?".Proceedings of the Royal Society B: Biological Sciences.276(1670): 3037–3045.doi:10.1098/rspb.2009.0413.PMC2817118.PMID19474041.
  58. ^abSahney, S.; Benton, M.J.; Falcon-Lang, H.J. (2010)."Rainforest collapse triggered Pennsylvanian tetrapod diversification in Euramerica"(PDF).Geology.38(12): 1079–1082.Bibcode:2010Geo....38.1079S.doi:10.1130/G31182.1.Archivedfrom the original on 11 October 2011.Retrieved28 August2011.
  59. ^Thomas, Chris D.; Cameron, Alison; Green, Rhys E.; Bakkenes, Michel; Beaumont, Linda J.; Collingham, Yvonne C.; Erasmus, Barend F. N.; de Siqueira, Marinez Ferreira; Grainger, Alan; Hannah, Lee; Hughes, Lesley; Huntley, Brian; van Jaarsveld, Albert S.; Midgley, Guy F.; Miles, Lera; Ortega-Huerta, Miguel A.; Townsend Peterson, A.; Phillips, Oliver L.; Williams, Stephen E. (January 2004)."Extinction risk from climate change"(PDF).Nature.427(6970): 145–148.Bibcode:2004Natur.427..145T.doi:10.1038/nature02121.PMID14712274.S2CID969382.Archived(PDF)from the original on 29 April 2019.Retrieved30 November2019.
  60. ^Bhattacharya, Shaoni (7 January 2004)."Global warming threatens millions of species".New Scientist.Archivedfrom the original on 21 April 2010.Retrieved28 May2010.the effects of climate change should be considered as great a threat to biodiversity as the "Big Three" —habitat destruction,invasions by alien speciesand overexploitation by humans.
  61. ^Handwerk, Brian; Hendwerk, Brian (April 2006)."Global Warming Could Cause Mass Extinctions by 2050, Study Says".National Geographic News. Archived fromthe originalon 12 June 2017.Retrieved27 October2017.
  62. ^Gibbon, J. Whitfield; Scott, David E.; Ryan, Travis J.; Buhlmann, Kurt A.; Tuberville, Tracey D.; Metts, Brian S.; Greene, Judith L.; Mills, Tony; Leiden, Yale; Poppy, Sean; Winne, Christopher T. (2000)."The Global Decline of Reptiles, Déjà Vu Amphibians".BioScience.50(8): 653.doi:10.1641/0006-3568(2000)050[0653:TGDORD]2.0.CO;2.S2CID12094030.Archivedfrom the original on 13 December 2019.Retrieved14 July2019.
  63. ^Martins, Maria João Fernandes; Puckett, T. Markham; Lockwood, Rowan; Swaddle, John P.; Hunt, Gene (April 2018)."High male sexual investment as a driver of extinction in fossil ostracods".Nature.556(7701): 366–369.Bibcode:2018Natur.556..366M.doi:10.1038/s41586-018-0020-7.PMID29643505.S2CID4925632.Archivedfrom the original on 2 October 2022.Retrieved16 September2022.
  64. ^abSahney, S.; Benton, M.J. (2008)."Recovery from the most profound mass extinction of all time".Proceedings of the Royal Society B: Biological Sciences.275(1636): 759–765.doi:10.1098/rspb.2007.1370.PMC2596898.PMID18198148.
  65. ^Benton, M.J. (2005).When Life Nearly Died: The Greatest Mass Extinction of All Time.Thames & Hudson.ISBN978-0-500-28573-2.
  66. ^Ritchie, Hannah(20 April 2021)."Wild mammals have declined by 85% since the rise of humans, but there is a possible future where they flourish".Our World in Data.Archivedfrom the original on 16 February 2023.Retrieved19 April2023.
  67. ^American Museum of Natural History."National Survey Reveals Biodiversity Crisis – Scientific Experts Believe We are in the Midst of the Fastest Mass Extinction in Earth's HistoryArchived10 April 2012 at theWayback Machine".Retrieved September 20, 2006.
  68. ^Vignieri, S. (25 July 2014)."Vanishing fauna (Special issue)".Science.345(6195): 392–412.Bibcode:2014Sci...345..392V.doi:10.1126/science.345.6195.392.PMID25061199.
  69. ^Ceballos, Gerardo; Ehrlich, Paul R.; Raven, Peter H. (1 June 2020)."Vertebrates on the brink as indicators of biological annihilation and the sixth mass extinction".PNAS.117(24): 13596–13602.Bibcode:2020PNAS..11713596C.doi:10.1073/pnas.1922686117.PMC7306750.PMID32482862.
  70. ^Wilson, E.O. (30 April 2012).""E. O. Wilson wants to know why you're not protesting in the streets"".Grist(Interview). Interviewed by Lisa Hymas.Archivedfrom the original on 4 November 2017.Retrieved16 January2014.E.O. Wilson repeats his estimation in 2012.
  71. ^J.H.Lawton and R.M.May,Extinction rates,Oxford UniversityPress, Oxford, UK
  72. ^abDe Vos, Jurriaan M.; Joppa, Lucas N.; Gittleman, John L.; Stephens, Patrick R.; Pimm, Stuart L. (April 2015)."Estimating the normal background rate of species extinction: Background Rate of Extinction"(PDF).Conservation Biology.29(2): 452–462.Bibcode:2015ConBi..29..452D.doi:10.1111/cobi.12380.PMID25159086.S2CID19121609.Archived(PDF)from the original on 4 November 2018.Retrieved30 November2019.
  73. ^Carrington D (2 February 2021)."Economics of biodiversity review: what are the recommendations?".The Guardian.Archivedfrom the original on 24 May 2022.Retrieved21 December2021.
  74. ^Dasgupta, Partha(2021)."The Economics of Biodiversity: The Dasgupta Review Headline Messages"(PDF).UK government. p. 1.Archived(PDF)from the original on 20 May 2022.Retrieved21 December2021.Biodiversity is declining faster than at any time in human history. Current extinction rates, for example, are around 100 to 1,000 times higher than the baseline rate, and they are increasing.
  75. ^Pimm, S. L.; Jenkins, C. N.; Abell, R.; Brooks, T. M.; Gittleman, J. L.; Joppa, L. N.; Raven, P. H.; Roberts, C. M.; Sexton, J. O. (30 May 2014). "The biodiversity of species and their rates of extinction, distribution, and protection".Science.344(6187): 1246752.doi:10.1126/science.1246752.PMID24876501.S2CID206552746.
  76. ^Sutter, John D. (12 December 2016)."How to stop the sixth mass extinction".CNN.Archivedfrom the original on 13 December 2016.Retrieved3 January2017.
  77. ^Graham, Chris (11 July 2017)."Earth undergoing sixth 'mass extinction' as humans spur 'biological annihilation' of wildlife".The Telegraph.Archivedfrom the original on 11 January 2022.Retrieved23 July2017.
  78. ^Greenfield, Patrick (13 January 2020)."UN draft plan sets 2030 target to avert Earth's sixth mass extinction".The Guardian.Archivedfrom the original on 24 February 2021.Retrieved14 January2020.
  79. ^Yeung, Jessie (14 January 2020)."We have 10 years to save Earth's biodiversity as mass extinction caused by humans takes hold, UN warns".CNN.Archivedfrom the original on 15 February 2021.Retrieved14 January2020.
  80. ^Cohen, Li (15 September 2020)."More than 150 countries made a plan to preserve biodiversity a decade ago. A new report says they mostly failed".CBS News.Archivedfrom the original on 15 May 2022.Retrieved23 September2020.
  81. ^Yeung, Jessie (16 September 2020)."The world set a 2020 deadline to save nature but not a single target was met, UN report says".CNN.Archivedfrom the original on 15 May 2022.Retrieved23 September2020.
  82. ^Weston, Phoebe (13 January 2021)."Top scientists warn of 'ghastly future of mass extinction' and climate disruption".The Guardian.Archivedfrom the original on 13 January 2021.Retrieved19 January2021.
  83. ^Bradshaw, Corey J. A.; Ehrlich, Paul R.; Beattie, Andrew; Ceballos, Gerardo; Crist, Eileen; Diamond, Joan; Dirzo, Rodolfo; Ehrlich, Anne H.; Harte, John; Harte, Mary Ellen; Pyke, Graham; Raven, Peter H.; Ripple, William J.; Saltré, Frédérik; Turnbull, Christine; Wackernagel, Mathis; Blumstein, Daniel T. (2021)."Underestimating the Challenges of Avoiding a Ghastly Future".Frontiers in Conservation Science.1.doi:10.3389/fcosc.2020.615419.
  84. ^Hooker, Jerry J.;Collinson, Margaret E.; Sille, Nicholas P. (2004)."Eocene–Oligocene mammalian faunal turnover in the Hampshire Basin, UK: calibration to the global time scale and the major cooling event"(PDF).Journal of the Geological Society.161(2): 161–172.Bibcode:2004JGSoc.161..161H.doi:10.1144/0016-764903-091.S2CID140576090.Archived(PDF)from the original on 8 August 2023.Retrieved25 August2023.
  85. ^abcdef"Extinctions: Georges Cuvier".evolution.berkeley.edu.Archivedfrom the original on 29 April 2017.Retrieved4 May2017.
  86. ^abcdRowland, Stephen (2009)."Thomas Jefferson, extinction, and the evolving view of Earth history in the late eighteenth and early nineteenth centuries".GSA Memoirs.203:225–246.Archivedfrom the original on 1 September 2015.Retrieved5 May2017.
  87. ^abcdefLyells, Charles (1854).The Principles of Geology or, The Modern Changes of the Earth and its Inhabitants Considered as Illustrative of Geology.New York: Appleton Co.Archivedfrom the original on 25 October 2016.Retrieved5 May2017.
  88. ^abcdefgBressan, David (17 August 2011)."On the Extinction of Species".Scientific American Blog Network.Archivedfrom the original on 22 December 2017.Retrieved5 May2017.[self-published source?]
  89. ^abcdVidal, Fernando; Dias, Nélia (2015).Endangerment, Biodiversity and Culture.Routledge.ISBN978-1-317-53807-3.[page needed]
  90. ^Inwood, Stephen (2005).The Forgotten Genius: The Biography of Robert Hooke, 1635–1703.MacAdam/Cage Publishing. p.403.ISBN978-1-59692-115-3.hooke nautilus.
  91. ^abcMolyneux, Thomas(April 1697). "II. A discourse concerning the large horns frequently found under ground in Ireland, concluding from them that the great American deer, call'd a moose, was formerly common in that Island: with remarks on some other things natural to that country".Philosophical Transactions of the Royal Society of London.19(227): 489–512.Bibcode:1695RSPT...19..489M.doi:10.1098/rstl.1695.0083.S2CID186207711.
  92. ^Ideas: A History from Fire to Freud(Peter WatsonWeidenfeld & NicolsonISBN0-297-60726-X)[page needed]
  93. ^abcdefgTrevor, Palmer (2003).Perilous planet earth: catastrophes and catastrophism through the ages.Cambridge University Press.ISBN978-0-521-81928-2.OCLC912273245.[page needed]
  94. ^abM. J. S., Rudwick;Cuvier, Georges(1998).Georges Cuvier, fossil bones, and geological catastrophes: new translations & interpretations of the primary texts.University of Chicago Press.ISBN978-0-226-73106-3.OCLC45730036.[page needed]
  95. ^Corsi, Pietro (1988).The age of Lamarck: evolutionary theories in France, 1790–1830.University of California Press.ISBN978-0-520-05830-9.OCLC898833548.[page needed]
  96. ^"The Lost World".The New Yorker.9 December 2013.Archivedfrom the original on 3 February 2023.Retrieved9 February2022.
  97. ^Einhorn, Catrin (27 January 2021)."Shark Populations Are Crashing, With a 'Very Small Window' to Avert Disaster".The New York Times.Archivedfrom the original on 31 January 2021.Retrieved31 January2021.
  98. ^Pacoureau, Nathan; Rigby, Cassandra L.; Kyne, Peter M.; Sherley, Richard B.; Winker, Henning; Carlson, John K.; Fordham, Sonja V.; Barreto, Rodrigo; Fernando, Daniel; Francis, Malcolm P.; Jabado, Rima W.; Herman, Katelyn B.; Liu, Kwang-Ming; Marshall, Andrea D.; Pollom, Riley A.; Romanov, Evgeny V.; Simpfendorfer, Colin A.; Yin, Jamie S.; Kindsvater, Holly K.; Dulvy, Nicholas K. (28 January 2021). "Half a century of global decline in oceanic sharks and rays".Nature.589(7843): 567–571.Bibcode:2021Natur.589..567P.doi:10.1038/s41586-020-03173-9.hdl:10871/124531.PMID33505035.S2CID231723355.
  99. ^C. Cormack Gates; Curtis H. Freese; Peter J.P. Gogan; Mandy Kotzman (2010).American bison: status survey and conservation guidelines 2010.IUCN. p. 15.ISBN978-2-8317-1149-2.Retrieved6 November2011.
  100. ^Walsh, Bruce.ExtinctionArchived1997-08-02 at theWayback Machine.Bioscience at University of Arizona. Retrieved July 26, 2006.
  101. ^Committee on Recently Extinct Organisms. "Why Care About Species That Have Gone Extinct?Archived13 July 2006 at theWayback Machine".Retrieved July 30, 2006.
  102. ^International Programme on Chemical Safety (1989). "DDT and its Derivatives – Environmental AspectsArchived27 September 2006 at theWayback Machine".Environmental Health Criteria 83. Retrieved September 20, 2006.
  103. ^"DDT and its derivatives (EHC 9, 1979)".Archivedfrom the original on 25 February 2021.Retrieved26 September2020.
  104. ^Diamond, Jared(2005)."A Tale of Two Farms".Collapse.Penguin. pp. 15–17.ISBN978-0-670-03337-9.
  105. ^Drewry, Rachel. "Ecotourism: Can it save the orangutans?ArchivedFebruary 16, 2007, at theWayback Machine"Inside Indonesia.Retrieved January 26, 2007.
  106. ^The Wildlands ProjectArchivedNovember 22, 2005, at theWayback Machine.Retrieved January 26, 2007.
  107. ^Alliance for Zero ExtinctionsArchivedApril 23, 2011, at theWayback Machine.Retrieved January 26, 2007.
  108. ^Ehrlich, Anne (1981).Extinction: The Causes and Consequences of the Disappearance of Species.Random House, New York.ISBN978-0-394-51312-6.
  109. ^Benatar, David(2008).Better Never to Have Been: The Harm of Coming into Existence.Oxford University Press. p.197.ISBN978-0-19-954926-9.It is noteworthy that human concern about human extinction takes a different form from human concern (where there is any) about the extinction of non-human species. Most humans who are concerned about the extinction of non-human species are not concerned about the individual animals whose lives are cut short in the passage to extinction, even though that is one of the best reasons to be concerned about extinction (at least in its killing form). The popular concern about animal extinction is usually concern for humans—that we shall live in a world impoverished by the loss of one aspect of faunal diversity, that we shall no longer be able to behold or use that species of animal. In other words, none of the typical concerns about human extinction are applied to non-human species extinction.
  110. ^Hickel, Jason(2021).Less is More: How Degrowth Will Save the World.Windmill Books. p. 80.ISBN978-1786091215.It's no wonder that we react so nonchalantly to the ever-mounting statistics about the crisis of mass extinction. We have a habit of taking this information with surprising calm. We don't weep. We don't get worked up. Why? Because we see humans as fundamentally separate from the rest of the living community. Those species are out there, in the environment. They aren't in here; they aren't part of us. It is not surprising that we behave this way. After all, this is the core principle of capitalism: that the world is not really alive, and it is certainly not our kin, but rather just stuff to be extracted and discarded – and that includes most of the human beings living here too. From its very first principles, capitalism has set itself at war against life itself.
  111. ^"Smallpox".WHO Factsheet.Archived fromthe originalon 21 September 2007.
  112. ^Normile, Dennis (21 March 2008). "Driven to Extinction".Science.319(5870): 1606–1609.doi:10.1126/science.319.5870.1606.PMID18356500.S2CID46157093.
  113. ^"Polio cases in the world in 2015".The Global Polio Eradication Initiative.Archivedfrom the original on 19 February 2016.Retrieved17 February2016.
  114. ^"This Species is Close to Extinction and That's a Good Thing".Time.23 January 2015.Archivedfrom the original on 24 February 2016.Retrieved17 February2016.
  115. ^abJudson, Olivia(25 September 2003)."A Bug's Death".The New York Times.Archivedfrom the original on 6 March 2016.Retrieved17 February2016.
  116. ^Paulson, Steve (4 April 2016)."Why a famous biologist wants to eradicate killer mosquitoes".The World from PRX.Archivedfrom the original on 9 February 2022.Retrieved9 February2022.
  117. ^Bruto da Costa, B. F.; Sant' Anna, J. F.; dos Santos, A. C.; de Araujo Alvares, M. G. (1916).Sleeping Sickness, A Record of Four Years' War against It in the Island of Principe.Translated by Lieutenant Colonel J. A. Wyllie.Lisbon:Centro Colonial (Baillière Tindalland Cox). pp. xxii+260.S2CID82867664.(OtherS2CID82229617)
  118. ^S., J. W. W. (1916)."The Eradication of Sleeping Sickness from Principe".Nature.98(2460).Nature Research:311–312.Bibcode:1916Natur..98..311J.doi:10.1038/098311a0.S2CID3964040.
  119. ^Simarro, Pere P; Jannin, Jean; Cattand, Pierre (26 February 2008)."Eliminating Human African Trypanosomiasis: Where Do We Stand and What Comes Next?".PLOS Medicine.5(2).Public Library of Science(PLoS): e55.doi:10.1371/journal.pmed.0050055.PMC2253612.PMID18303943.S2CID17608648.
  120. ^Bouyer, Jérémy; Carter, Neil H; Batavia, Chelsea;Nelson, Michael Paul(19 December 2018)."The Ethics of Eliminating Harmful Species: The Case of the Tsetse Fly".BioScience.69(2).American Institute of Biological Sciences(OUP): 125–135.doi:10.1093/biosci/biy155.PMC6377282.PMID30792543.S2CID67788418.
  121. ^A. Zitner (24 December 2000)."Cloned Goat Would Revive Extinct Line".Los Angeles Times.Archived fromthe originalon 25 August 2011.Retrieved17 May2010.
  122. ^Nicholas Wade(19 November 2008)."Regenerating a Mammoth for $10 Million".The New York Times.Archivedfrom the original on 12 March 2017.Retrieved17 May2010.The cell could be converted into an embryo and brought to term by an elephant, a project he estimated would cost some $10 million. "This is something that could work, though it will be tedious and expensive,"
  123. ^Folch, J.; et al. (2009)."First birth of an animal from an extinct subspecies (Capra pyrenaica pyrenaica) by cloning".Theriogenology.71(6): 1026–1034.doi:10.1016/j.theriogenology.2008.11.005.PMID19167744.
  124. ^Steve Connor (2 February 2009)."Cloned goat dies after attempt to bring species back from extinction".The Independent.London.Archivedfrom the original on 13 October 2017.Retrieved17 May2010.
  125. ^Gray, Richard; Dobson, Roger (31 January 2009)."Extinct ibex is resurrected by cloning".Telegraph.London.Archivedfrom the original on 11 January 2022.

Further reading

edit
edit