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124-503: The occurrence of the interchange was first discussed in 1876 by the "father of biogeography ", Alfred Russel Wallace . Wallace had spent five years exploring and collecting specimens in the Amazon basin . Others who made significant contributions to understanding the event in the century that followed include Florentino Ameghino , W. D. Matthew , W. B. Scott , Bryan Patterson , George Gaylord Simpson and S. David Webb. The Pliocene timing of

248-602: A clade (i.e., monophyletic ). However, although they would have had little effective competition, all extant New World monkeys appear to derive from a radiation that occurred long afterwards, in the Early Miocene about 18 Ma ago. Subsequent to this, monkeys apparently most closely related to titis island-hopped to Cuba , Hispaniola , and Jamaica . Additionally, a find of seven 21-Ma-old apparent cebid teeth in Panama suggests that South American monkeys had dispersed across

372-399: A big porcupine), and all native South American mammals larger than about 65 kg (the size of a big capybara or giant anteater ). In contrast, the largest surviving native North American mammal, the wood bison , can exceed 900 kg (2,000 lb), and the largest surviving Nearctic migrant to South America, Baird's tapir , can reach 400 kg (880 lb). The near-simultaneity of

496-476: A combination of historical factors such as: speciation , extinction , continental drift , and glaciation . Through observing the geographic distribution of species, we can see associated variations in sea level , river routes, habitat, and river capture . Additionally, this science considers the geographic constraints of landmass areas and isolation, as well as the available ecosystem energy supplies. Over periods of ecological changes, biogeography includes

620-524: A degree of protection from human predation. Extant or extinct (†) North American taxa whose ancestors migrated out of South America and reached the modern territory of the contiguous United States : Fish Amphibians Birds Mammals Extant or extinct (†) North American taxa whose ancestors migrated out of South America, but failed to reach the contiguous United States and were confined to Mexico and Central America: Invertebrates Fish Amphibians Biogeography Biogeography

744-610: A diverse group of native ungulates known as the Meridiungulata : notoungulates (the "southern ungulates"), litopterns , astrapotheres , pyrotheres and xenungulates . A few non- therian mammals – monotremes , gondwanatheres , dryolestids and possibly cimolodont multituberculates  – were also present in the Paleocene ; while none of these diversified significantly and most lineages did not survive long, forms like Necrolestes and Patagonia remained as recently as

868-433: A few small marsupial and avian predators like didelphine opossums and seriemas ). It was originally thought that the native South American predator guild, including sparassodonts , carnivorous opossums like Thylophorops and Hyperdidelphys , armadillos such as Macroeuphractus , terror birds , and teratorns , as well as early-arriving immigrant Cyonasua -group procyonids , were driven to extinction during

992-421: A global scale. GIS can show certain processes on the earth's surface like whale locations, sea surface temperatures , and bathymetry. Current scientists also use coral reefs to delve into the history of biogeography through the fossilized reefs. Two global information systems are either dedicated to, or have strong focus on, biogeography (in the form of the spatial location of observations of organisms), namely

1116-419: A great impact on Charles Darwin , who was inspired to consider species adaptations and evolution after learning about botanical geography. De Candolle was the first to describe the differences between the small-scale and large-scale distribution patterns of organisms around the globe. Several additional scientists contributed new theories to further develop the concept of biogeography. Charles Lyell developed

1240-587: A group of animals) accidentally floated over on driftwood or mangrove rafts. Hutias (Capromyidae) would subsequently colonize the West Indies as far as the Bahamas , reaching the Greater Antilles by the early Oligocene. Over time, some caviomorph rodents evolved into larger forms that competed with some of the native South American ungulates, which may have contributed to the gradual loss of diversity suffered by

1364-583: A horse, Pachyrukhos resembled a rabbit, Homalodotherium was a semibipedal, clawed browser like a chalicothere , and horned Trigodon looked like a rhinoceros . Both groups started evolving in the Lower Paleocene, possibly from condylarth stock, diversified, dwindled before the great interchange, and went extinct at the end of the Pleistocene. The pyrotheres and astrapotheres were also strange, but were less diverse and disappeared earlier, well before

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1488-479: A land area roughly six times greater than was available to South American species. North American species were thus products of a larger and more competitive arena, where evolution would have proceeded more rapidly. They tended to be more efficient and brainier , generally able to outrun and outwit their South American counterparts, who were products of an evolutionary backwater. In the cases of ungulates and their predators, South American forms were replaced wholesale by

1612-399: A more dedicated shearing action; these have been interpreted as "omnivory leading towards carnivory" and as more specialized carnivory in posterior studies. There is evidence that T. chapadmalensis re-appropriated burrows from other digging mammals, as well as outright consuming them. Thylophorops species as a whole tended to be terrestrial rather than arboreal. Thylophorops lived at

1736-413: A number of methods have been developed to produce arguably more complete "predictive" or "modelled" distributions for species based on their associated environmental or other preferences (such as availability of food or other habitat requirements); this approach is known as either Environmental niche modelling (ENM) or Species distribution modelling (SDM). Depending on the reliability of the source data and

1860-542: A number of types of rodents . The larger members of the reverse migration were ground sloths , terror birds , glyptodonts , pampatheres , capybaras , and the notoungulate Mixotoxodon (the only South American ungulate known to have invaded Central America). In general, the initial net migration was symmetrical. Later on, however, the Neotropic species proved far less successful than the Nearctic. This difference in fortunes

1984-490: A possible cause of this turnover, but this is still controversial. A similar pattern occurs in the crocodilian fauna, where modern crocodiles ( Crocodylus ) dispersed to South America during the Pliocene and became the dominant member of crocodilian communities after the late Miocene extinction of the previously dominant large native crocodilians such as the giant caiman Purussaurus and giant gharial Gryposuchus , which

2108-643: A primarily indirect role in the extinctions in the Americas by simply facilitating the movement of humans southeastward from Beringia to North America. The reason that a number of groups went extinct in North America but lived on in South America (while no examples of the opposite pattern are known) appears to be that the dense rainforest of the Amazon basin and the high peaks of the Andes provided environments that afforded

2232-987: A result of tectonic uplift (or subsidence ), natural damming created by a landslide , or headward or lateral erosion of the watershed between adjacent basins. Biogeography is a synthetic science, related to geography , biology , soil science , geology , climatology , ecology and evolution . Some fundamental concepts in biogeography include: The study of comparative biogeography can follow two main lines of investigation: There are many types of biogeographic units used in biogeographic regionalisation schemes, as there are many criteria ( species composition , physiognomy , ecological aspects) and hierarchization schemes: biogeographic realms (ecozones), bioregions ( sensu stricto ), ecoregions , zoogeographical regions , floristic regions , vegetation types, biomes , etc. The terms biogeographic unit, biogeographic area can be used for these categories, regardless of rank. In 2008, an International Code of Area Nomenclature

2356-572: A second lineage of African monkeys also rafted to and at least briefly colonized South America. Ucayalipithecus remains dating from the Early Oligocene of Amazonian Peru are, by morphological analysis, deeply nested within the family Parapithecidae of the Afro-Arabian radiation of parapithecoid simians , with dental features markedly different from those of platyrrhines . The Old World members of this group are thought to have become extinct by

2480-425: A time when South America's older predatory guilds were dismantling. It co-existed with only a few sparassodont and phorusrhacid taxa like Thylacosmilus and Llallawavis , and it, as well as similar opossum species, evolved to fill the ecological blanks. A similar case is observed with the carnivorous armadillo Macroeuphractus , a product of this same era of faunal turn-overs. As mentioned above, there

2604-488: A whole suite of predictor variables for biogeographic analysis, including satellite imaging and processing of the Earth. Two main types of satellite imaging that are important within modern biogeography are Global Production Efficiency Model (GLO-PEM) and Geographic Information Systems (GIS). GLO-PEM uses satellite-imaging gives "repetitive, spatially contiguous, and time specific observations of vegetation". These observations are on

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2728-424: Is an alternate view than that of Linnaeus. Buffon's law eventually became a principle of biogeography by explaining how similar environments were habitats for comparable types of organisms. Buffon also studied fossils which led him to believe that the Earth was over tens of thousands of years old, and that humans had not lived there long in comparison to the age of the Earth. Following the period of exploration came

2852-476: Is an extinct genus of didelphine opossums from the Pliocene of South America . Compared to their close didelphine cousins like the living Philander and Didelphis (and like the still living Lutreolina ) opossums, Thylophorops displays specialization towards carnivory , and one species, T. lorenzinii , is the largest known opossum of all time, which could imply a macropredatory role. Thylophorops

2976-443: Is another example of parallel evolution. This invasion most likely came from Africa. The crossing from West Africa to the northeast corner of Brazil was much shorter then, due to continental drift , and may have been aided by island hopping (e.g. via St. Paul's Rocks , if they were an inhabitable island at the time) and westward oceanic currents. Crossings of the ocean were accomplished when at least one fertilised female (more commonly

3100-423: Is clear that carnivorans benefitted from it. Several groups of carnivorans such as dogs and cats underwent an adaptive radiation in South America after dispersing there, and the greatest modern diversity of canids in the world is in South America. The eventual triumph of the Nearctic migrants was ultimately based on geography, which played into the hands of the northern invaders in two crucial respects. The first

3224-475: Is controversial; it is regarded by a number of investigators as a misinterpreted fossil of a different gomphothere, Notiomastodon , and biostratigraphy dates the site to the Pleistocene. The early date proposed for Surameryx has also been met with skepticism. Megalonychid and mylodontid ground sloths island-hopped to North America by 9 Ma ago. A basal group of sloths had colonized the Antilles previously, by

3348-404: Is in the geological similarities between varying locations around the globe, the geographic distribution of some fossils (including the mesosaurs ) on various continents, and the jigsaw puzzle shape of the landmasses on Earth. Though Wegener did not know the mechanism of this concept of Continental Drift, this contribution to the study of biogeography was significant in the way that it shed light on

3472-473: Is on how the environment and humans affect the distribution of species as well as other manifestations of Life such as species or genetic diversity. Biogeography is being applied to biodiversity conservation and planning, projecting global environmental changes on species and biomes, projecting the spread of infectious diseases, invasive species, and for supporting planning for the establishment of crops. Technological evolving and advances have allowed for generating

3596-472: Is only 600 km (370 mi) from the Isthmus of Panama. Other groups of native South American predators have not been studied in as much depth. Terror birds have often been suggested to have been driven to extinction by placental carnivorans, though this hypothesis has not been investigated in detail. Titanis dispersed from South America to North America against the main wave of carnivoran migrations, being

3720-628: Is rather consistently recovered as a didelphine opossum, most often compared to and usually falling within the Didelphis , Philander and Lutreolina group. Within Thylophorops itself, there are three recognized species: Thylophorops species (as well as several other contemporary opossum genera ) show a high degree of speciation towards carnivory compared to most living didelphines. Their premolar and molar teeth were proportionally larger than those of living opossums and their grinding facets imply

3844-577: Is the branch that studies distribution of fungi, such as mushrooms . Knowledge of spatial variation in the numbers and types of organisms is as vital to us today as it was to our early human ancestors , as we adapt to heterogeneous but geographically predictable environments . Biogeography is an integrative field of inquiry that unites concepts and information from ecology , evolutionary biology , taxonomy , geology , physical geography , palaeontology , and climatology . Modern biogeographic research combines information and ideas from many fields, from

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3968-445: Is the study of the distribution of species and ecosystems in geographic space and through geological time . Organisms and biological communities often vary in a regular fashion along geographic gradients of latitude , elevation , isolation and habitat area . Phytogeography is the branch of biogeography that studies the distribution of plants. Zoogeography is the branch that studies distribution of animals. Mycogeography

4092-497: Is thought to be related to the loss of wetlands habitat across northern South America. Whether this revised scenario with a reduced role for competitive exclusion applies to other groups of South American mammals such as notoungulates and litopterns is unclear, though some authors have pointed out a protracted decline in South American native ungulate diversity since the middle Miocene. Regardless of how this turnover happened, it

4216-607: The Age of Enlightenment in Europe, which attempted to explain the patterns of biodiversity observed by Buffon and Linnaeus. At the birth of the 19th century, Alexander von Humboldt, known as the "founder of plant geography", developed the concept of physique generale to demonstrate the unity of science and how species fit together. As one of the first to contribute empirical data to the science of biogeography through his travel as an explorer, he observed differences in climate and vegetation. The Earth

4340-613: The Galápagos Islands (formerly also of South America), giant Dipsochelys tortoises of the Seychelles (formerly also of Madagascar ), giant meiolaniid turtles on Lord Howe Island , New Caledonia and Vanuatu (previously also of Australia), ground sloths on the Antilles , Steller's sea cows off the Commander Islands and woolly mammoths on Wrangel Island and Saint Paul Island . The glacial retreat may have played

4464-667: The Global Biodiversity Information Facility (GBIF: 2.57 billion species occurrence records reported as at August 2023) and, for marine species only, the Ocean Biodiversity Information System (OBIS, originally the Ocean Biogeographic Information System : 116 million species occurrence records reported as at August 2023), while at a national scale, similar compilations of species occurrence records also exist such as

4588-463: The Lesser Antilles to Anguilla . One group has proposed that a number of large Neartic herbivores actually reached South America as early as 9–10 Ma ago, in the late Miocene, via an early incomplete land bridge. These claims, based on fossils recovered from rivers in southwestern Peru, have been viewed with caution by other investigators, due to the lack of corroborating finds from other sites and

4712-558: The Miocene . Marsupials appear to have traveled via Gondwanan land connections from South America through Antarctica to Australia in the late Cretaceous or early Tertiary . One living South American marsupial, the monito del monte , has been shown to be more closely related to Australian marsupials than to other South American marsupials ( Ameridelphia ); however, it is the most basal australidelphian, meaning that this superorder arose in South America and then dispersed to Australia after

4836-721: The Pliocene from North America via the Caribbean. Tortoises also arrived in South America in the Oligocene. They were long thought to have come from North America, but a recent comparative genetic analysis concludes that the South American genus Chelonoidis (formerly part of Geochelone ) is actually most closely related to African hingeback tortoises . Tortoises are aided in oceanic dispersal by their ability to float with their heads up, and to survive up to six months without food or water. South American tortoises then went on to colonize

4960-870: The Trans-Mexican Volcanic Belt . The challenge this climatic asymmetry (see map on right) presented was particularly acute for Neotropic species specialized for tropical rainforest environments, which had little prospect of penetrating beyond Central America. As a result, Central America currently has 41 mammal species of Neotropical origin, compared to only three for temperate North America. However, species of South American origin ( marsupials , xenarthrans , caviomorph rodents , and monkeys ) still comprise only 21% of species from nonflying, nonmarine mammal groups in Central America , while North American invaders constitute 49% of species from such groups in South America . Thus, climate alone cannot fully account for

5084-444: The hoatzin , a weak-flying bird of South American rainforests. The earliest traditionally recognized mammalian arrival from North America was a procyonid that island-hopped from Central America before the Isthmus of Panama land bridge formed, around 7.3 Ma ago. This was South America's first eutherian carnivore. South American procyonids then diversified into forms now extinct (e.g. the "dog-coati" Cyonasua , which evolved into

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5208-543: The megafauna , ground sloths were notably successful emigrants; four different lineages invaded North America. A megalonychid representative, Megalonyx , spread as far north as the Yukon and Alaska, and might well have invaded Eurasia had a suitable habitat corridor across Beringia been present. Generally speaking, however, the dispersal and subsequent explosive adaptive radiation of sigmodontine rodents throughout South America (leading to over 80 currently recognized genera )

5332-531: The situation in Australia ). Sparassodonts and giant opossums shared the ecological niches for large predators with fearsome flightless "terror birds" ( phorusrhacids ), whose closest living relatives are the seriemas . North America also had large terrestrial predatory birds during the early Cenozoic (the related bathornithids ), but they died out before the GABI in the Early Miocene , about 20 million years ago. Through

5456-420: The therians ). Their low metabolic rate may in turn have been advantageous in allowing them to subsist on less abundant or less nutritious food sources. Unfortunately, the defensive adaptations of the large xenarthrans would have offered little protection against humans armed with spears and other projectiles . At the end of the Pleistocene epoch, about 12,000 years ago, three dramatic developments occurred in

5580-476: The 36 volume Histoire Naturelle, générale et particulière , in which he argued that varying geographical regions would have different forms of life. This was inspired by his observations comparing the Old and New World, as he determined distinct variations of species from the two regions. Buffon believed there was a single species creation event, and that different regions of the world were homes for varying species, which

5704-505: The Amazon basin, Orinoco basin, and Guianas ) with an exceptionally low (flat) topographic relief, the many waterways have had a highly reticulated history over geological time . In such a context, stream capture is an important factor affecting the evolution and distribution of freshwater organisms. Stream capture occurs when an upstream portion of one river drainage is diverted to the downstream portion of an adjacent basin. This can happen as

5828-463: The Americas at roughly the same time (geologically speaking). Paleoindians invaded and occupied the New World (although humans may have been living in the Americas, including what is now the southern US and Chile, more than 15,000 years ago), the last glacial period came to an end, and a large fraction of the megafauna of both North and South America went extinct. This wave of extinctions swept off

5952-476: The Eocene, possibly via Antarctica. Similarly, free-tailed bats (Molossidae) may have reached South America from Africa in as many as five dispersals, starting in the Eocene. Emballonurids may have also reached South America from Africa about 30 Ma ago, based on molecular evidence. Vespertilionids may have arrived in five dispersals from North America and one from Africa. Natalids are thought to have arrived during

6076-596: The GABI by competitive exclusion from immigrating placental carnivorans , and that this turnover was abrupt. However, the turnover of South America's predator guild was more complex, with competition only playing a limited role. In the case of sparassodonts and carnivorans, which has been the most heavily studied, little evidence shows that sparassodonts even encountered their hypothesized placental competitors. Many supposed Pliocene records of South American carnivorans have turned out to be misidentified or misdated. Sparassodonts appear to have been declining in diversity since

6200-492: The Great American Interchange. Opossums and porcupines were among the most successful northward migrants, reaching as far as Canada and Alaska , respectively. Most major groups of xenarthrans were present in North America until the end-Pleistocene Quaternary extinction event (as a result of at least eight successful invasions of temperate North America, and at least six more invasions of Central America only). Among

6324-588: The Gómez Farias Region, Tamaulipas, Mexico , which has been described as "ground-breaking" and "a classic treatise in historical biogeography". Martin applied several disciplines including ecology , botany , climatology , geology , and Pleistocene dispersal routes to examine the herpetofauna of a relatively small and largely undisturbed area, but ecologically complex, situated on the threshold of temperate – tropical (nearctic and neotropical) regions, including semiarid lowlands at 70 meters elevation and

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6448-604: The Indian Ocean was much narrower than it is today, and that South America was closer to the Antarctic, one would be hard pressed to explain the presence of many "ancient" lineages of perching birds in Africa, as well as the mainly South American distribution of the suboscines . Paleobiogeography also helps constrain hypotheses on the timing of biogeographic events such as vicariance and geodispersal , and provides unique information on

6572-467: The Late Oligocene. Qatrania wingi of lower Oligocene Fayum deposits is considered the closest known relative of Ucayalipithecus . Remarkably, the descendants of those few bedraggled " waifs " that crawled ashore from their rafts of African flotsam in the Eocene now constitute more than twice as many of South America's species as the descendants of all the flightless mammals previously resident on

6696-448: The Origin of Species were devoted to geographical distribution. The first discoveries that contributed to the development of biogeography as a science began in the mid-18th century, as Europeans explored the world and described the biodiversity of life. During the 18th century most views on the world were shaped around religion and for many natural theologists, the bible. Carl Linnaeus , in

6820-478: The Theory of Continental Drift in 1912, though it was not widely accepted until the 1960s. This theory was revolutionary because it changed the way that everyone thought about species and their distribution around the globe. The theory explained how continents were formerly joined in one large landmass, Pangea , and slowly drifted apart due to the movement of the plates below Earth's surface. The evidence for this theory

6944-603: The Theory of Uniformitarianism after studying fossils. This theory explained how the world was not created by one sole catastrophic event, but instead from numerous creation events and locations. Uniformitarianism also introduced the idea that the Earth was actually significantly older than was previously accepted. Using this knowledge, Lyell concluded that it was possible for species to go extinct. Since he noted that Earth's climate changes, he realized that species distribution must also change accordingly. Lyell argued that climate changes complemented vegetation changes, thus connecting

7068-631: The U.K. National Biodiversity Network , the Atlas of Living Australia , and many others. In the case of the oceans, in 2017 Costello et al. analyzed the distribution of 65,000 species of marine animals and plants as then documented in OBIS, and used the results to distinguish 30 distinct marine realms, split between continental-shelf and offshore deep-sea areas. Since it is self evident that compilations of species occurrence records cannot cover with any completeness, areas that have received either limited or no sampling,

7192-706: The West Indies and Galápagos Islands (the Galápagos tortoise ). A number of clades of American geckos seem to have rafted over from Africa during both the Paleogene and Neogene. Skinks of the related genera Mabuya and Trachylepis apparently dispersed across the Atlantic from Africa to South America and Fernando de Noronha , respectively, during the last 9 Ma. Surprisingly, South America's burrowing amphisbaenians and blind snakes also appear to have rafted from Africa, as does

7316-466: The ability of South America's xenarthrans to compete effectively against the northerners represents a special case. The explanation for the xenarthrans' success lies in part in their idiosyncratic approach to defending against predation, based on possession of body armor or formidable claws . The xenarthrans did not need to be fleet-footed or quick-witted to survive. Such a strategy may have been forced on them by their low metabolic rate (the lowest among

7440-414: The anticipated effects of climate change can also be used to show potential changes in species distributions that may occur in the future based on such scenarios. Paleobiogeography goes one step further to include paleogeographic data and considerations of plate tectonics . Using molecular analyses and corroborated by fossils , it has been possible to demonstrate that perching birds evolved first in

7564-485: The bear-like Chapalmalania ). However, all extant procyonid genera appear to have originated in North America. The first South American procyonids may have contributed to the extinction of sebecid crocodilians by eating their eggs, but this view has not been universally viewed as plausible. The procyonids were followed to South America by rafting or island-hopping hog-nosed skunks and sigmodontine rodents . The oryzomyine tribe of sigmodontine rodents went on to colonize

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7688-421: The biotic and abiotic features of the Earth in his book, Cosmos . Augustin de Candolle contributed to the field of biogeography as he observed species competition and the several differences that influenced the discovery of the diversity of life. He was a Swiss botanist and created the first Laws of Botanical Nomenclature in his work, Prodromus. He discussed plant distribution and his theories eventually had

7812-677: The case of Jamaica, oryzomyine rodents of North American origin were able to enter the region only after invading South America. The formation of the Isthmus of Panama led to the last and most conspicuous wave, the Great American Biotic Interchange (GABI), starting around 2.7 Ma ago. This included the immigration into South America of North American ungulates (including camelids , tapirs , deer and horses ), proboscids ( gomphotheres ), carnivorans (including felids such as cougars , jaguars and saber-toothed cats , canids , mustelids , procyonids and bears ) and

7936-496: The caviomorph rodents and platyrrhine monkeys, were less impacted by the interchange than most of South America's 'old-timers', although the caviomorphs suffered a significant loss of diversity, including the elimination of the largest forms (e.g. the dinomyids ). With the exception of the North American porcupine and several extinct porcupines and capybaras, however, they did not migrate past Central America. Due in large part to

8060-483: The continent ( 372 caviomorph and monkey species versus 136 marsupial and xenarthran species ). Many of South America's bats may have arrived from Africa during roughly the same period, possibly with the aid of intervening islands, although by flying rather than floating. Noctilionoid bats ancestral to those in the neotropical families Furipteridae , Mormoopidae , Noctilionidae , Phyllostomidae , and Thyropteridae are thought to have reached South America from Africa in

8184-582: The continent-wide extinctions. The climate change took place worldwide, but had little effect on the megafauna in Africa and southern Asia, where megafaunal species had coevolved with humans . Numerous very similar glacial retreats had occurred previously within the ice age of the last several million years without ever producing comparable waves of extinction in the Americas or anywhere else. Similar megafaunal extinctions have occurred on other recently populated land masses (e.g. Australia , Japan , Madagascar , New Zealand , and many smaller islands around

8308-618: The continued success of the xenarthrans, one area of South American ecospace the Nearctic invaders were unable to dominate was the niches for megaherbivores. Before 12,000 years ago, South America was home to about 25 species of herbivores weighing more than 1,000 kg (2,200 lb), consisting of Neotropic ground sloths, glyptodonts, and toxodontids, as well as gomphotheres and camelids of Nearctic origin. Native South American forms made up about 75% of these species. However, none of these megaherbivores has survived. Armadillos, opossums and porcupines are present in North America today because of

8432-475: The development of biogeography as a science. The scientific theory of biogeography grows out of the work of Alexander von Humboldt (1769–1859), Francisco Jose de Caldas (1768–1816), Hewett Cottrell Watson (1804–1881), Alphonse de Candolle (1806–1893), Alfred Russel Wallace (1823–1913), Philip Lutley Sclater (1829–1913) and other biologists and explorers. The patterns of species distribution across geographical areas can usually be explained through

8556-420: The development of the fields of conservation biology and landscape ecology . Classic biogeography has been expanded by the development of molecular systematics , creating a new discipline known as phylogeography . This development allowed scientists to test theories about the origin and dispersal of populations, such as island endemics . For example, while classic biogeographers were able to speculate about

8680-427: The early Miocene . In contrast, megatheriid and nothrotheriid ground sloths did not migrate north until the formation of the isthmus. Terror birds may have also island-hopped to North America as early as 5 Ma ago. The Caribbean Islands were populated primarily by species from South America, due to the prevailing direction of oceanic currents, rather than to a competition between North and South American forms. Except in

8804-505: The early Pleistocene. Bears , cats, and skunks do not appear in South America until the early Pleistocene (about 1 Ma ago or slightly earlier). Otters and other groups of procyonids (i.e., coatis , raccoons ) have been suggested to have dispersed to South America in the Miocene based on genetic data, but no remains of these animals have been found even at heavily sampled northern South American fossil sites such as La Venta (Colombia) , which

8928-496: The environmental surroundings to varying species. This largely influenced Charles Darwin in his development of the theory of evolution. Charles Darwin was a natural theologist who studied around the world, and most importantly in the Galapagos Islands . Darwin introduced the idea of natural selection, as he theorized against previously accepted ideas that species were static or unchanging. His contributions to biogeography and

9052-403: The extinct meiolaniid turtles. Marsupials remaining in South America included didelphimorphs ( opossums ), paucituberculatans ( shrew opossums ) and microbiotheres (monitos del monte). Larger predatory relatives of these also existed, such as the borhyaenids and the saber-toothed Thylacosmilus ; these were sparassodont metatherians, which are no longer considered to be true marsupials. As

9176-451: The extinction of a large proportion of the South American fauna. (No extinctions in North America are plainly linked to South American immigrants.) Native South American ungulates did poorly, with only a handful of genera withstanding the northern onslaught. (Several of the largest forms, macraucheniids and toxodontids , have long been recognized to have survived to the end of the Pleistocene. Recent fossil finds indicate that one species of

9300-403: The extinction of the last sparassodonts), not correlated with the arrival of carnivorans in South America, with terrestrial carnivore diversity being low thereafter. This has been suggested to have opened up ecological niches and allowed carnivorans to establish themselves in South America due to low competition. A meteor impact 3.3 million years ago in southern South America has been suggested as

9424-1074: The face of the Earth many of the successful participants of the GABI, as well as other species that had not migrated. All the pampatheres, glyptodonts, ground sloths, equids, proboscideans, giant short-faced bears , dire wolves , and machairodont species of both continents disappeared. The last of the South and Central American notoungulates and litopterns died out, as well as North America's giant beavers , lions , dholes , cheetahs , and many of its antilocaprid , bovid , cervid , tapirid and tayassuid ungulates. Some groups disappeared over most or all of their original range, but survived in their adopted homes, e.g. South American tapirs, camelids, and tremarctine bears (cougars and jaguars may have been temporarily reduced to South American refugia also). Others, such as capybaras, survived in their original range, but died out in areas to which they had migrated. Notably, this extinction pulse eliminated all Neotropic migrants to North America larger than about 15 kg (the size of

9548-403: The fact that almost all of the specimens in question have been collected as float in rivers without little to no stratigraphic control. These taxa are a gomphothere ( Amahuacatherium ), peccaries ( Sylvochoerus and Waldochoerus ), tapirs and Surameryx , a palaeomerycid (from a family probably ancestral to cervids). The identification of Amahuacatherium and the dating of its site

9672-597: The factors affecting organism distribution, and to predict future trends in organism distribution. Often mathematical models and GIS are employed to solve ecological problems that have a spatial aspect to them. Biogeography is most keenly observed on the world's islands . These habitats are often much more manageable areas of study because they are more condensed than larger ecosystems on the mainland. Islands are also ideal locations because they allow scientists to look at habitats that new invasive species have only recently colonized and can observe how they disperse throughout

9796-566: The first appearance of canids or felids in South America. Thylacosmilids last occur about 3 Ma ago and appear to be rarer at pre-GABI Pliocene sites than Miocene ones. In general, sparassodonts appear to have been mostly or entirely extinct by the time most nonprocyonid carnivorans arrived, with little overlap between the groups. Purported ecological counterparts between pairs of analogous groups (thylacosmilids and saber-toothed cats, borhyaenids and felids, hathliacynids and weasels ) neither overlap in time nor abruptly replace one another in

9920-453: The formation of regional biotas. For example, data from species-level phylogenetic and biogeographic studies tell us that the Amazonian teleost fauna accumulated in increments over a period of tens of millions of years, principally by means of allopatric speciation, and in an arena extending over most of the area of tropical South America (Albert & Reis 2011). In other words, unlike some of

10044-733: The formation of the connection between North and South America was discussed in 1910 by Henry Fairfield Osborn . Analogous interchanges occurred earlier in the Cenozoic, when the formerly isolated land masses of India and Africa made contact with Eurasia about 56 and 30 Ma ago, respectively. After the late Mesozoic breakup of Gondwana , South America spent most of the Cenozoic era as an island continent whose "splendid isolation" allowed its fauna to evolve into many forms found nowhere else on Earth, most of which are now extinct . Its endemic mammals initially consisted primarily of metatherians ( marsupials and sparassodonts ), xenarthrans , and

10168-477: The former Lifemapper project at the University of Kansas (now continued as a part of BiotaPhy ) and AquaMaps , which as at 2023 contain modelled distributions for around 200,000 terrestrial, and 33,000 species of teleosts , marine mammals and invertebrates, respectively. One advantage of ENM/SDM is that in addition to showing current (or even past) modelled distributions, insertion of changed parameters such as

10292-558: The fossil record. Procyonids dispersed to South America by at least 7 Ma ago, and had achieved a modest endemic radiation by the time other carnivorans arrived ( Cyonasua -group procyonids ). However, procyonids do not appear to have competed with sparassodonts, the procyonids being large omnivores and sparassodonts being primarily hypercarnivorous . Other groups of carnivorans did not arrive in South America until much later. Dogs and weasels appear in South America about 2.9 Ma ago, but do not become abundant or diverse until

10416-641: The geographical distribution of organisms around the globe. Alfred Russel Wallace studied the distribution of flora and fauna in the Amazon Basin and the Malay Archipelago in the mid-19th century. His research was essential to the further development of biogeography, and he was later nicknamed the "father of Biogeography". Wallace conducted fieldwork researching the habits, breeding and migration tendencies, and feeding behavior of thousands of species. He studied butterfly and bird distributions in comparison to

10540-459: The greater success of species of Nearctic origin during the interchange. The second and more important advantage geography gave to the northerners is related to the land area in which their ancestors evolved. During the Cenozoic, North America was periodically connected to Eurasia via Beringia , allowing repeated migrations back and forth to unite the faunas of the two continents. Eurasia was connected in turn to Africa , which contributed further to

10664-414: The horse-like proterotheriid litopterns did, as well. The notoungulate mesotheriids and hegetotheriids also managed to hold on at least part way through the Pleistocene.) South America's small marsupials , though, survived in large numbers, while the primitive -looking xenarthrans proved to be surprisingly competitive and became the most successful invaders of North America. The African immigrants,

10788-411: The importance of environmental and geographic similarities or differences as a result of climate and other pressures on the planet. Importantly, late in his career Wegener recognised that testing his theory required measurement of continental movement rather than inference from fossils species distributions. In 1958 paleontologist Paul S. Martin published A Biogeography of Reptiles and Amphibians in

10912-506: The inflow of nutrient-rich water of deep Pacific origin was blocked. The Pacific coast of South America cooled as the input of warm water from the Caribbean was cut off. This trend is thought to have caused the extinction of the marine sloths of the area. During the last 7 Ma, South America's terrestrial predator guild has changed from one composed almost entirely of nonplacental mammals ( metatherians ), birds , and reptiles to one dominated by immigrant placental carnivorans (with

11036-532: The interchange. The North American fauna was a typical boreoeutherian one, supplemented with Afrotherian proboscids . The invasions of South America started about 40 Ma ago (middle Eocene ), when caviomorph rodents arrived in South America. Their subsequent vigorous diversification displaced some of South America's small marsupials and gave rise to – among others – capybaras , chinchillas , viscachas , and New World porcupines . The independent development of spines by New and Old World porcupines

11160-420: The invaders, possibly a result of these advantages. The greater eventual success of South America's African immigrants compared to its native early Cenozoic mammal fauna is another example of this phenomenon, since the former evolved over a greater land area; their ancestors migrated from Eurasia to Africa , two significantly larger continents, before finding their way to South America. Against this backdrop,

11284-556: The island and change it. They can then apply their understanding to similar but more complex mainland habitats. Islands are very diverse in their biomes , ranging from the tropical to arctic climates. This diversity in habitat allows for a wide range of species study in different parts of the world. One scientist who recognized the importance of these geographic locations was Charles Darwin , who remarked in his journal "The Zoology of Archipelagoes will be well worth examination". Two chapters in On

11408-486: The isthmus on the marine biota of the area was the inverse of its effect on terrestrial organisms, a development that has been termed the "Great American Schism". The connection between the east Pacific Ocean and the Caribbean (the Central American Seaway ) was severed, setting now-separated populations on divergent evolutionary paths. Caribbean species also had to adapt to an environment of lower productivity after

11532-464: The large carnivorous metatherians declined, and before the arrival of most types of carnivorans , predatory opossums such as Thylophorops temporarily attained larger size (about 7 kg). Metatherians and a few xenarthran armadillos, such as Macroeuphractus , were the only South American mammals to specialize as carnivores ; their relative inefficiency created openings for nonmammalian predators to play more prominent roles than usual (similar to

11656-406: The largest Mesozoic crocodyliforms). They shared their habitat with one of the largest turtles of all time, the 3.3 m (11 ft) Stupendemys . Xenarthrans are a curious group of mammals that developed morphological adaptations for specialized diets very early in their history. In addition to those extant today ( armadillos , anteaters , and tree sloths ), a great diversity of larger types

11780-404: The latter after the early Oligocene. By the Pliocene, some caviomorphs (e.g., Josephoartigasia monesi ) attained sizes on the order of 500 kg (1,100 lb) or larger. Later (by 36 Ma ago), primates followed, again from Africa in a fashion similar to that of the rodents. Primates capable of migrating had to be small. Like caviomorph rodents, South American monkeys are believed to be

11904-475: The megafaunal extinctions with the glacial retreat and the peopling of the Americas has led to proposals that both climate change and human hunting played a role. Although the subject is contentious, a number of considerations suggest that human activities were pivotal. The extinctions did not occur selectively in the climatic zones that would have been most affected by the warming trend, and no plausible general climate-based megafauna-killing mechanism could explain

12028-479: The mid-18th century, improved our classifications of organisms through the exploration of undiscovered territories by his students and disciples. When he noticed that species were not as perpetual as he believed, he developed the Mountain Explanation to explain the distribution of biodiversity; when Noah's ark landed on Mount Ararat and the waters receded, the animals dispersed throughout different elevations on

12152-426: The middle Miocene , with many of the niches once occupied by small sparassodonts being increasingly occupied by carnivorous opossums, which reached sizes of up to roughly 8 kg (~17 lbs). Whether sparassodonts competed with carnivorous opossums or whether opossums began occupying sparassodont niches through passive replacement is still debated. Borhyaenids last occur in the late Miocene, about 4 Ma before

12276-429: The monito del monte split off. Monotrematum , a 61-Ma-old platypus-like monotreme fossil from Patagonia , may represent an Australian immigrant. Paleognath birds ( ratites and South American tinamous ) may have made a similar migration around the same time to Australia and New Zealand . Other taxa that may have dispersed by the same route (if not by flying or oceanic dispersal ) are parrots , chelid turtles, and

12400-515: The most important and consequential developments in biogeography has been to show how multiple organisms, including mammals like monkeys and reptiles like squamates , overcame barriers such as large oceans that many biogeographers formerly believed were impossible to cross. See also Oceanic dispersal . Biogeography now incorporates many different fields including but not limited to physical geography, geology, botany and plant biology, zoology, general biology, and modelling. A biogeographer's main focus

12524-499: The mountain. This showed different species in different climates proving species were not constant. Linnaeus' findings set a basis for ecological biogeography. Through his strong beliefs in Christianity, he was inspired to classify the living world, which then gave way to additional accounts of secular views on geographical distribution. He argued that the structure of an animal was very closely related to its physical surroundings. This

12648-683: The nature of the models employed (including the scales for which data are available), maps generated from such models may then provide better representations of the "real" biogeographic distributions of either individual species, groups of species, or biodiversity as a whole, however it should also be borne in mind that historic or recent human activities (such as hunting of great whales , or other human-induced exterminations) may have altered present-day species distributions from their potential "full" ecological footprint. Examples of predictive maps produced by niche modelling methods based on either GBIF (terrestrial) or OBIS (marine, plus some freshwater) data are

12772-476: The northernmost cloud forest in the western hemisphere at over 2200 meters. The publication of The Theory of Island Biogeography by Robert MacArthur and E.O. Wilson in 1967 showed that the species richness of an area could be predicted in terms of such factors as habitat area, immigration rate and extinction rate. This added to the long-standing interest in island biogeography . The application of island biogeography theory to habitat fragments spurred

12896-642: The only large native South American carnivore to accomplish this. However, it only managed to colonize a small part of North America for a limited time, failing to diversify and going extinct in the early Pleistocene (1.8 Ma ago); the modest scale of its success has been suggested to be due to competition with placental carnivorans. Terror birds also decline in diversity after about 3 Ma ago. At least one genus of relatively small terror birds, Psilopterus , appears to have survived to as recently as about 96,000 years ago. The native carnivore guild appears to have collapsed completely roughly 3 Ma ago (including

13020-571: The origins of species in the Hawaiian Islands , phylogeography allows them to test theories of relatedness between these populations and putative source populations on various continents, notably in Asia and North America . Biogeography continues as a point of study for many life sciences and geography students worldwide, however it may be under different broader titles within institutions such as ecology or evolutionary biology. In recent years, one of

13144-495: The physiological and ecological constraints on organismal dispersal to geological and climatological phenomena operating at global spatial scales and evolutionary time frames. The short-term interactions within a habitat and species of organisms describe the ecological application of biogeography. Historical biogeography describes the long-term, evolutionary periods of time for broader classifications of organisms. Early scientists, beginning with Carl Linnaeus , contributed to

13268-448: The presence or absence of geographical barriers. His observations led him to conclude that the number of organisms present in a community was dependent on the amount of food resources in the particular habitat. Wallace believed species were dynamic by responding to biotic and abiotic factors. He and Philip Sclater saw biogeography as a source of support for the theory of evolution as they used Darwin's conclusion to explain how biogeography

13392-420: The region of Australia or the adjacent Antarctic (which at that time lay somewhat further north and had a temperate climate). From there, they spread to the other Gondwanan continents and Southeast Asia – the part of Laurasia then closest to their origin of dispersal – in the late Paleogene , before achieving a global distribution in the early Neogene . Not knowing that at the time of dispersal,

13516-409: The seaway separating Central and South America by that early date. However, all extant Central American monkeys are believed to be descended from much later migrants, and there is as yet no evidence that these early Central American cebids established an extensive or long-lasting population, perhaps due to a shortage of suitable rainforest habitat at the time. Fossil evidence presented in 2020 indicates

13640-649: The skies over late Miocene South America (6 Ma ago) soared one of the largest flying birds known, Argentavis , a teratorn that had a wing span of 6 m or more, and which may have subsisted in part on the leftovers of Thylacosmilus kills. Terrestrial sebecid ( metasuchian ) crocodyliforms with ziphodont teeth were also present at least through the middle Miocene and maybe to the Miocene-Pliocene boundary. Some of South America's aquatic crocodilians, such as Gryposuchus , Mourasuchus and Purussaurus , reached monstrous sizes, with lengths up to 12 m (comparable to

13764-521: The smaller ones) contained multiple climatic zones that would have been affected differently by any climate changes occurring at the time. However, on sizable islands far enough offshore from newly occupied territory to escape immediate human colonization, megafaunal species sometimes survived for many thousands of years after they or related species became extinct on the mainland; examples include giant kangaroos in Tasmania, giant Chelonoidis tortoises of

13888-484: The species that made their way to North America. South America, though, was connected only to Antarctica and Australia, two much smaller and less hospitable continents, and only in the early Cenozoic. Moreover, this land connection does not seem to have carried much traffic (apparently no mammals other than marsupials and perhaps a few monotremes ever migrated by this route), particularly in the direction of South America. This means that Northern Hemisphere species arose within

14012-428: The study of plant and animal species in: their past and/or present living refugium habitat ; their interim living sites; and/or their survival locales. As writer David Quammen put it, "...biogeography does more than ask Which species? and Where . It also asks Why? and, what is sometimes more crucial, Why not? ." Modern biogeography often employs the use of Geographic Information Systems (GIS), to understand

14136-416: The theory of evolution were different from those of other explorers of his time, because he developed a mechanism to describe the ways that species changed. His influential ideas include the development of theories regarding the struggle for existence and natural selection. Darwin's theories started a biological segment to biogeography and empirical studies, which enabled future scientists to develop ideas about

14260-447: The well-known insular faunas ( Galapagos finches , Hawaiian drosophilid flies, African rift lake cichlids ), the species-rich Amazonian ichthyofauna is not the result of recent adaptive radiations . For freshwater organisms, landscapes are divided naturally into discrete drainage basins by watersheds , episodically isolated and reunited by erosional processes. In regions like the Amazon Basin (or more generally Greater Amazonia,

14384-440: The world, such as Cyprus , Crete , Tilos and New Caledonia ) at different times that correspond closely to the first arrival of humans at each location. These extinction pulses invariably swept rapidly over the full extent of a contiguous land mass, regardless of whether it was an island or a hemisphere-spanning set of connected continents. This was true despite the fact that all the larger land masses involved (as well as many of

14508-402: Was a matter of climate . Any species that reached Panama from either direction obviously had to be able to tolerate moist tropical conditions . Those migrating southward would then be able to occupy much of South America without encountering climates that were markedly different. However, northward migrants would have encountered drier or cooler conditions by the time they reached the vicinity of

14632-400: Was divided into regions which he defined as tropical, temperate, and arctic and within these regions there were similar forms of vegetation. This ultimately enabled him to create the isotherm, which allowed scientists to see patterns of life within different climates. He contributed his observations to findings of botanical geography by previous scientists, and sketched this description of both

14756-529: Was important to a George Louis Buffon's rival theory of distribution. Closely after Linnaeus, Georges-Louis Leclerc, Comte de Buffon observed shifts in climate and how species spread across the globe as a result. He was the first to see different groups of organisms in different regions of the world. Buffon saw similarities between some regions which led him to believe that at one point continents were connected and then water separated them and caused differences in species. His hypotheses were described in his work,

14880-504: Was manifested in several ways. Northwardly migrating animals often were not able to compete for resources as well as the North American species already occupying the same ecological niches; those that did become established were not able to diversify much, and in some cases did not survive for long. Southwardly migrating Nearctic species established themselves in larger numbers and diversified considerably more, and are thought to have caused

15004-548: Was present, including pampatheres , the ankylosaur -like glyptodonts , predatory euphractines , various ground sloths , some of which reached the size of elephants (e.g. Megatherium ), and even semiaquatic to aquatic marine sloths . The notoungulates and litopterns had many strange forms, such as Macrauchenia , a camel-like litoptern with a small proboscis . They also produced a number of familiar-looking body types that represent examples of parallel or convergent evolution : one-toed Thoatherium had legs like those of

15128-656: Was proposed for biogeography. It achieved limited success; some studies commented favorably on it, but others were much more critical, and it "has not yet gained a significant following". Similarly, a set of rules for paleobiogeography has achieved limited success. In 2000, Westermann suggested that the difficulties in getting formal nomenclatural rules established in this field might be related to "the curious fact that neither paleo- nor neobiogeographers are organized in any formal groupings or societies, nationally (so far as I know) or internationally — an exception among active disciplines." Thylophorops Thylophorops

15252-496: Was similar to a record of species inheritance. Key findings, such as the sharp difference in fauna either side of the Wallace Line , and the sharp difference that existed between North and South America prior to their relatively recent faunal interchange , can only be understood in this light. Otherwise, the field of biogeography would be seen as a purely descriptive one. Moving on to the 20th century, Alfred Wegener introduced

15376-587: Was vastly more successful (both spatially and by number of species) than any northward migration of South American mammals. Other examples of North American mammal groups that diversified conspicuously in South America include canids and cervids, both of which currently have three or four genera in North America, two or three in Central America, and six in South America. Although members of Canis (specifically, coyotes ) currently range only as far south as Panama, South America still has more extant genera of canids than any other continent. The effect of formation of

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