Evolutionary anachronism, also known as "ecological anachronism",[1] is a term initially referring to attributes of native plant species (primarily fruit, but also thorns) that seemed best explained as having been favorably selected in the past due to their coevolution with plant-eating megafauna that are now extinct. Diminished effectiveness and distance of seed dispersal by fruit-eating mammals inhabiting the same ecosystems today suggest maladaptation. Maladaptation of such fruiting plants will intensify as ongoing climate change shifts the physical and ecological conditions within their current geographic range.[2]
The concept was formulated by Costa Rican-based American ecologist Daniel H. Janzen[3] and carried broadly into scientific awareness when he and his coauthor, paleoecologist Paul S. Martin, published "Neotropical Anachronisms: The Fruits the Gomphotheres Ate" in the journal Science.[4] Among the largest of extinct fruit-eating mammals in the American tropics were the gomphotheres, related to modern elephants, which inspired the title chosen by Janzen and Martin for their 1982 paper. As they explained,
There are prominent members of the lowland forest flora of Costa Rica whose fruit and seed traits can best be explained by viewing them as anachronisms. These traits were molded by evolutionary interactions with the Pleistocene megafauna (and earlier animals) but have not yet effectively responded to its absence.
The Janzen and Martin paper was preceded by a 1977 publication by American ecologist Stanley Temple. Temple attributed the decline of the Mauritiusendemic tree tambalacoque to human overharvesting to extinction of a large, flightless bird that had coevolved on the same tropical island: the dodo.[5] It was Janzen who applied the concept to some 18 fruiting plant species or genera in Costa Rica, while Martin took the lead on proposing a distinct seed dispersal syndrome: the "megafaunal dispersal syndrome" by comparing the maladapted neotropical fruits with similar forms in the tropics of Africa and Asia that were documented as dispersed by elephants still inhabiting those continents.[1]
Anachronistic fruits of temperate North America, collected by Connie Barlow. Includes pods of devil's claw (top), honey locust (long and curvy at middle) and mesquite (beige at bottom), along with other fruits of the forests and deserts of the USA.
Two decades after the "neotropical anachronisms" concept was published and named, science writer Connie Barlow aggregated its history and subsequent applications into a popular science book: The Ghosts of Evolution: Nonsensical Fruit, Missing Partners, and Other Ecological Anachronisms.[1] In shaping the book's title, Barlow drew upon a 1992 essay by Paul S. Martin titled "The Last Entire Earth".[6] Martin had written:
In the shadows along the trail I keep an eye out for the ghosts, the beasts of the ice age. What is the purpose of the thorns on the mesquites in my backyard in Tucson? Why do they and honey locusts have sugary pods so attractive to livestock? Whose foot is devil's claw intended to intercept? Such musings add magic to a walk and may help to liberate us from tunnel vision, the hubris of the present, the misleading notion that nature is self-evident.[6]
The honey locust mentioned in Martin's excerpt is a native tree of eastern North America. Because it is favored for planting along urban streets and parking lots, Barlow was very familiar with it while she was working on her book in New York City. Its long, curving pods became a prominent part of her book.[1] Later, other writers also popularized its lost partnership with ice age ghosts.[7][8]
One animal-with-animal form of evolutionary anachronism also gained popular attention. As reported in the New York Times, "Pronghorn's Speed May Be Legacy of Past Predators", John A. Byers hypothesized that the antelope-like pronghorn of America's grasslands was still running from a Pleistocene ghost that had been much faster than America's native wolves. This ghost was the American cheetah.[9][10]
Megafaunal dispersal syndrome
Pulp surrounds the large seeds of Gymnocladus dioica (Kentucky coffeetree) within its large, stiff podThis Indian rhinoceros was happy to eat more than a dozen pulp-filled pods of Kentucky coffeetree, suggesting that its rhino ancestors in North America may have prompted the plant's megafaunal dispersal syndrome.
Seed dispersal syndromes are complexes of fruit traits that enable plants to disperse seeds by wind, water, or mobile animals. The kind of fruits that birds are attracted to eat are usually small, with only a thin protective skin, and the colors are red or dark shades of blue or purple. Fruits categorized as mammal syndrome are bigger than bird fruits. They may possess a tough rind or husk and emit a strong odor when ripe. Because mammals (other than primates) tend to have poor color vision, these fruits usually retain a dull coloration of brown, burnished yellow, orange, or will remain green when ripe.[1] The megafaunal dispersal syndrome refers to those attributes of fruits that evolved in order to attract megafauna (animals that weigh or weighed more than 44 kilograms) as primary dispersal agents.[4][12] Following the Late Pleistocene megafaunal extinctions, most species of large herbivores have become extinct outside of Africa (and to a lesser extent Asia), thereby reducing the effectiveness of seed dispersal—except for the fruits that attracted cultivation by humans.[4]
Common megafaunal dispersal traits
Large fruit, best suited to be consumed whole by large animals without seed loss.
Fruit grows on or close to the trunk, or on stout branches.
Indehiscent fruit that retains its seeds upon ripening.
Seeds deter or elude being ground up by teeth through having a thick, tough or hard endocarp; or bitter, peppering or nauseating toxins. They are also difficult to separate from the pulp, which is tasty and soft, to deter seed spitting.
The seeds benefit from—or even require—physical or chemical abrasion to germinate.
If tropical, the fruit drops on or just before ripening, stopping monkeys from eating them. In colder climates, the fruit stays on the branch for a prolonged time, keeping it away from predation by ineffectual seed dispersers like rodents.
"Looks, feels, smells, and tastes" like other fruits known to be dispersed by megafauna where megafauna still exists.[4][1]
Ecological indicators of missing dispersal partners
The fruit either rots where it falls or is ineffectually disseminated by current dispersal agents.
The plant is more common where livestock (proxy for megafauna) are present.
The seeds germinate and grow well in upland habitats where planted, but the species almost exclusively inhabits floodplains (where water flow disperses the seeds) in the wild.
The geographic range is inexplicably patchy or restricted.[4][1]
Extremely limited or unrecorded seed dispersal in areas where elephants were extirpated; at least one Kenyan forest lacks seedlings and younger trees altogether.[1]
Toxic, at least to humans, and resistant to trampling.[13]
Five species of giant tortoises of the genus Cylindraspis lived in the islands before they were hunted to extinction in the 18th and 19th centuries.[13]
The fruit weighs over 20kg and contains the largest seeds in the world. No known animal eats the fruit, and the surviving trees appear to be the result of vegetative reproduction. Mature fruits do not float and are killed by sea water, unlike real coconuts.[15] The species is not thought to have dispersed over water, but to have evolved locally in the Seychelles after they broke off from the Indian Plate 66 million years ago.[16] No megafauna is known from the archipelago before the Seychelles giant tortoise arrived 23 million years ago; they eat much smaller fruit, and the distribution of tortoises and plants in the islands is inconsistent with co-dispersal.[17]
One species per island, all with pyrena smaller than their relatives in continental Africa and Madagascar, which are dispersed by large mammals and birds; smaller fruits are consumed by tortoises.[17]L. loddigesii is resistant to trampling.[13]
The colonization of each island by the palms coincides with the arrival of giant tortoises.[17]
In decline due to the absence of animals removing its pulp. The fruit is colonized by fungihyphae and the seeds rot without germinating. The fruit is only sporadically consumed by the Mauritian flying fox, which does not ingest the seeds.[14]
Coarse, unpalatable leaves that are avoided by grazers like introduced rabbits when other grasses are available. Tussock-grass dominated Round Island before rabbits were removed, after which it immediately declined and was replaced by other native grasses.[13]
Peach-sized fruit that ripens from green to brown, much larger than its relatives present in the island and which are eaten by flying birds. The seed is in fact too large to be ingested by flying birds, and introduced pigs and monkeys destroy the seeds rather than disperse them. The tambalacoque evolved locally from smaller-seeded species of the genus Sideroxylon (formerly Calvaria), which is found in Africa and Madagascar. Temple reported in 1977 that only 13 trees were left, all of them over three hundred years old, and that seeds could not germinate at all without being ingested and abraded first. However, these claims have since been debunked.[1]
Temple proposed that the tambalacoque had a strict mutualist relation with the dodo, extinct since c.1662.[1] Critics argued that the seeds were dispersed by a giant tortoise instead, and that the tambalacoque might even have descended from seeds contained in a tortoise drifting from Madagascar, as tortoises are buoyant and colonize islands easily. In the Galapagos, ingestion by giant tortoises reduces seed dormancy in the Galapagos wild tomato, Solanum galapagense. Two species of giant tortoise were present in Mauritius before being hunted to extinction in the 18th century, the saddle-backed and domed Mauritius giant tortoise. However, the seeds have a harder cover than those eaten by tortoises, which have no gizzard; this might imply to a mutualistic relation with a bird after all, and the dodo was the only bird large enough to ingest the seeds. In any case, it was later found that germination was not favored by ingestion and abrasion of the seeds, but by pulp removal. The fruit that remains whole is colonized by fungi and its seeds rot.[1] The broad-billed parrot was also a large bird, although a flying one, and had an even more powerful beak than the dodo.[14] The Mauritian giant skink is presumed to have been omnivorous.[14] The coconut crab existed formerly in Mauritius, but has since disappeared from the island.[14]
Heavily spined stems, apparently as defense against climbing browsers, but browsinglemurs are rare in their area of distribution. The only known living predator is the ring-tailed lemur.[19]
Endozoochorous dry forest tree with high genetic variation among subpopulations at the local scale but similar genetic differentiation among populations at the regional scale as relatives in South Africa, suggesting that the dispersal distance shrunk in the recent past.[21]
Fruit with fragile pericarp, tasty and nutritious pulp, and seeds with a tough, thick testa, clearly adapted for animal dispersal but lacking any known disperser. Relatives in continental Africa dispersed by elephants and baboons. Very restricted geographic distribution.[15]
Archaeolemur,[15] a semiterrestrial, generalist lemur similar to a baboon that disappeared in the Middle Ages, and Pachylemur,[21] a close relative of the black-and-white ruffed lemur, but larger and more robust.[15]
Large seeds of variable size with hard cover.[15] Sharp serrated leaf edges and young plants resistant to trampling.[13]
The largest seeds may have been eaten by lemurs slightly larger than extant species,[15] while the leaves and young plants would resist predation by giant tortoises.[13]
Malagasy wire plants
Several unrelated species
Madagascar
Plants convergent with New Zealand's divaricating plants, adapted to resist browsing by large birds, rather than like their continental African relatives, which have defenses against ungulate browsers.[22]
Fruits 6–7cm long and 4–5cm wide, with substantial flesh and a single seed 4cm long and 2cm wide. The flesh is eaten by aye-ayes but rarely whole, and they may be satiated without removing all the flesh from the seed, indicating that they are not the intended disperser. Its Asian relatives are dispersed by large parrots and hornbills.[15]
Plants often thrive and even form monocultures in degraded areas, due to their efficient vegetative reproduction. Hard, one centimeter long seeds, not adapted for wind or water dispersal, surrounded by odoriferous, light blue arils. The only viable seeds were found in the manure of the black-and-white ruffed lemur, the largest living lemur.[15]
Unlike related species, the seeds are too large to be dispersed by ants and their low energy-to-water ratio make them unattractive to birds. The large legumes can be found directly beneath the shrub, in abundance and unopened, months after the end of the fruiting season.[1] Defensive spines are also common[citation needed], despite consumption of Acacia leaves by living marsupials being generally rare.[24]
Poor seed dispersal in spite of bright red, fleshy coatings. Brushtail possums eat the flesh but rarely carry the seeds. Many fruits fall in place and rot on the ground.[25]
Several species with a variable amount of defensive spines in the branches. The most spiny live in the Australian desert, where browsing marsupials are most rare.[24]
Fossil pollen records show great abundance 50,000 years ago (after the extinction of the megafauna) compared to 100,000 years ago, despite the climate being similar and in contrast to other tree species which declined.[24]
There is direct evidence of predation by Diprotodon.[24]
Critically endangered and limited to New Caledonia in the present, but pollen records show that it was also present in Australia before the Last Glacial Maximum. It is mostly found in the margins of streams and the seeds are dispersed by large birds.[24]
A primitive angiosperm with close relatives from the Middle Cretaceous.[27] Produces the largest seeds of any plant in Australia (225 grams), which are only sporadically dispersed by gravity and water.[24] Present naturally in only two locations 130km apart[27] and restricted mostly to low elevations and the margins of streams, yet translocation experiments found that the species germinates easily in upland rainforests. The seeds are nutritious but contain neurotoxins lethal to small mammals[24] and cattle. Cassowaries are known to avoid them.[27] The fruit has no pulp, but the seeds are easily divided into cotyledons, each of which can produce a different seedling. A large-jawed mammal might be able to feed on the seeds and disperse some of the seedlings uphill, if cotyledons fell from the mouth while chewing.[24]
Several defensive measures against large browsers, including wide, divaricate angle of branching, stiff and spiky twig tips, and small leaves widely separated along branchlets.[24] The defensive measures are lost when the plant reaches four meters, way above the reach of the largest local browsers - swamp and rock wallabies.[23]
Spiny leaves that are not eaten by any living mammal.[24] At least one species (H. eyreana) has camouflaged flowers, despite no living animal browsing it.[29]
Woody, spiny herbaceous species with relatives that are neither woody nor spiny. Presumed extinct until 1992, when a few clonal populations were discovered.[23]
Three anti-browser responses depending on its height: at grass level, the plant is soft but has a strong smell similar to stale urine, and induces headaches in humans; at shrub level, the plant is densely branched and has rigid, sharply pointed and outwardly reaching phyllodes; and at tree level (starting between two and three meters), the plant grows vertically, with soft phyllodes, and sheds all the rigid ones. However, the largest mammal in the area, the red kangaroo, rarely reaches two meters and is a grazer, not a browser. There are only three disjunct populations, but genetic testing shows that each is highly diverse, and similar in its genetic makeup to the others, indicating that they are recent remnants of a larger range area.[24] Seed regeneration is low and the species reproduces mainly clonally. The dense phyllodes of the shrub stage make it very vulnerable to fire, which might be another reason for its decline, as forest fires increased after the extinction of the megafauna.[23]
10% of New Zealand plants have a divaricating pattern of growth (i.e. they grow in thickets), a much larger proportion than elsewhere in the world. Like spines, a divaricating growth pattern reduces the action of large browsers, but it is more effective against browsing birds, while spines are more effective against browsing mammals. However, the only large browsers in New Zealand today are introduced deer.[1] These defenses disappear three meters above ground, at most.[23]
Moas - the larger species in particular, which have been identified as browsers from their preserved gizzard contents.[1] The largest species of all, the South Island giant moa, matches the height where the plant defenses disappear.[23]
Fruit with typical lizard dispersal syndrome features like most plants in New Zealand, but too large to be swallowed by any wild animal in the islands.[1]
The kawekaweau, an undescribed giant gecko last observed in 1870.[1][36]
Abundant pollen found in Medieval coprolites of kākāpō from the South Island, in an area where neither species is found today. Only known pollinator in the present is the lesser short-tailed bat.
An extreme living fossil, its genus existed already in the Jurassic and the species might go back to the Middle Cretaceous. Ginkgos were widespread through the Northern Hemisphere until the Paleocene, survived in North America until the end of the Miocene, and in Europe and Japan until the Pleistocene. Seeds are protected by a shell too fragile to deter mammals, since they are capable of mastication, but the pulp is poisonous to frugivores (including humans). Red-bellied tree squirrels (in China) and eastern gray squirrels (in North American parks and plantations) are known to extract seeds from the pulp and store them, but are only secondary dispersers. Fallen diaspores smell like rotten flesh after a few days on the ground, attracting carnivorans like the masked palm civet, leopard cat, and raccoon dog, which eat them whole; however, their marking of their territory through defecation also limits their ability as seed dispersers.[1]Pollination is exclusively by the wind, but the chemical profile of pollination drops is similar to those of insect-pollinated, or mixed wind and insect-pollinated Gnetophyta.[38]
Squirrel-like multituberculates, particularly Ptilodus.[1] Small carrion-eating dinosaurs both lived on the ground and lacked the powerful masticatory apparatus and gizzard stones of vegetarian species.[1] Several extinct, early pollinating insect lineages are known from the Middle Jurassic to the Early Cretaceous, before modern flowers evolved. Most are long-proboscid scorpion flies (Mecoptera), including Juracimbrophlebia, whose shape mimicked ginkgo leaves.[38] The unusual trunk and root growth pattern may have evolved in a pre-angiosperm world where the main competitors of the ginkgo were tree ferns, cycads and cycadeoids.[39]
Between 14 and 28 species of dioeciousparasitic plants with no visible stems, branches or leaves, but that produce enormous red flowers with a fetid, carrion-like smell. The smell attracts flies but they are poor pollinators. The fruits are giant berries around 14 centimeters long, with woody, cryptic cover; and smooth, oily flesh which smells and tastes like overripe coconut. The only observed dispersers are small rodents and treeshrews that eat part of the pulp and sometimes swallow seeds. Most species are endangered and have disjunct and extremely limited ranges.[1]
The original main pollinators might have been dung or carrion-eating beetles that became rarer as the megafauna declined.[1] The Asian elephant, Javan rhinoceros and Sumatran rhinoceros all used to, but are no longer present in Rafflesia's range, and might have been its intended seed dispersers.[1]
Seeds difficult to separate from the pulp, like in its Old World relatives, and highly toxic unless swallowed whole. Gray foxes, raccoons and American black bears are known seed dispersers, but they were less abundant before their natural predators and competitors like gray wolves, cougars and grizzlies were extirpated by humans, and defecate in certain places in order to mark their territory, limiting their dispersal potential. Virginia opossums consume the pulp but never swallow the seeds. The fruit is edible for a month before it falls from the tree and remains so for several months afterward.[1]
Squash relative with orange-sized fruit that often rots and dries on the ground next to the plant while the next year's fruit is already ripening. The plant grows well in dry uplands, yet is more commonly encountered in floodplains where flash floods provide occasional dispersal; hydrochory was proposed once as the main dispersal syndrome, but this is now rejected. High concentrations of cucurbitacin in the pulp and, to a lesser extent, seeds, makes it bitter to most animals. Domestic cattle and donkeys eat it rarely and mostly as a last resource. If eaten by a cow, the milk will become bitter to humans, and it is deadly to sheep and cattle in enough quantity. In Africa and Asia, such bitter fruit is most commonly eaten by the largest megaherbivores, elephants and rhinoceroses. The distribution is extremely patchy.[1]
One of the best known examples of zoochory that does not involve eating the fruit. In New Mexico, the burs, each containing two seeds, adhere to horse fur with such tenacity that they remain until retrieved by humans or the fur is shed. However, the burs fail to adhere to the fur of the largest wild ungulates in the area, deer.[1]
Historically reduced to northern Florida's Apalachicola river, which acted as refugium for many temperate trees during the ice ages. Unlike other species, the Florida nutmeg did not expand north when the climate became warmer in the Holocene, and successive blights killed all trees starting in the 1950s. The species survives mostly through asexual reproduction, generating new trees from surviving roots, and it is estimated that it will become extinct when the roots run out of reserves in about 50 years. However, trees introduced to colder, mountain areas in North Carolina thrive and are free of disease, suggesting that the species is better adapted to the current climate there than in Florida's.[41]
The Florida nutmeg might have depended on an unknown large mammal for long range seed dispersal, which became extinct before the ice age ended. Living squirrels are known to provide some dispersal, but this was only enough to ensure the species's survival up to recent times, not its re-expansion north.[41] Because the genus Torreya goes back to the Eocene, it has been suggested that squirrel-like multituberculates dispersed the seeds before squirrels evolved.[1]
Long, widely spaced and insufficiently densed thorns, better at dissuading larger African browsers like rhinoceroses and kudus than the local, narrow-muzzled white-tailed deer.[1]
Weather-resistant fruit (pods) that remains on the tree or the ground from one year to another, too large to be eaten by any wild animal in the area, but the seeds need abrasion to germinate. Horses ignore the fruit, but donkeys and mules will eat it on occasion. Large defensive thorns sometimes up to 20cm are also present, usually high above ground.[1]
The fruit is much larger than in related species dispersed by birds and fruit-eating bats, a considerable investment in a desert. Fruit-eating bats are not present in the Mojave, and birds eat parasiticinsects living in the Joshua tree's fruit but not the fruit itself. Ground squirrels eat the seeds but only sporadically, and pack rats eat fruit both on the tree and on the ground, but avoid the seeds, not acting as seed dispersers. The fruit is eaten full both by the largest wild mammals in the area (mule deer and bighorn sheep) and livestock including horses, donkeys and cattle, but they can only reach fruit on the ground or the lowest branches, leaving the numerous spines on the rest of the plant unexplained.[42] The fruit may grow at three meters above ground.[1]
The Western camel was 20% larger than the modern dromedary, allowing it to browse up to 4 meters. Although dromedaries have trouble swallowing whole seeds and are very selective eaters and poor seed dispersers as a result, this might have been different in larger Western camels. However, Western camel fossil dung contains only finely chewed plant remains, like in modern camels.[42] The American mastodon, Columbian mammoth and Gomphotherium all lived within the modern range of the Joshua tree and could reach even the tallest branches. Like modern elephants, they are presumed to have had an inefficient digestive system, making them both voracious eaters and perfect seed dispersers.[42] The Shasta ground sloth was common in western North America during the Pleistocene and has been identified as a primary yucca feeder from fossil feces, which are commonly found in desert caves. However, it was only the size of an American black bear and would have been limited to eating only fruit near the ground. It probably fed more often on smaller species of yucca.[42]
Defensive spines have backward-pointing teeth that attach to passing animals and the stems detach easily. The portions of the stem are transported for a while until they fall to the ground and grow into a new plant. The fruit is also ingested by many desert animals, but it grows above their reach as often as below. Fruit that grows highest may remain in place for months after ripening and fall only after desiccation, when it is not attractive to seed dispersers.[1]
Large range area but very low density. It is more common in floodplains even though it grows upland with no problem. The seeds are the largest of any species in the contiguous United States, but they are not harvested by rodents because they cannot break the pod's walls; they need abrasion to germinate. The pulp is sweet and slightly bitter, similar in taste to the honey locust, but also poisonous to livestock and humans (unless roasted) because of its high content in saponin and alkaloids. The seeds are more poisonous than the pulp, and often, large numbers of fallen pods and non-germinated seeds from preceding years can be found on the ground around a tree, trampled and rotten. The seeds die if they are not removed from the pod in time. Similar, related species in Africa are dispersed by elephants.[1][40][41]
Sweet and nutritious pods edible to humans and livestock. Horses and cattle act as dispersers and abrade the seeds walls, helping it germinate; foxes and coyotes eat the pods and disperse the seeds but do not abrade them. As a result, the mesquite's range began to expand after European colonization. The rest of the plant is armed with thorns and poisonous to livestock, limits the growth of grass and favors the establishment of nopales. At tree size, it is hard to kill because it will grow back from the root after being knocked down (which is done with tractors).[40] It was sought by the dromedaries of the United States Camel Corps while ignoring the grasses.[1]
Western camel.[1] Gomphotheres were large enough to knock adult trees, like elephants do to similar species in Africa, and might have fed on mesquite pods and prickly pears during the fruiting season.[1]
Defensive spines at heights far above the range of current browsers. The whole plant is consumed by camels in North Africa and Australia, where animal and plant alike have been introduced and are now feral, and was sought by the camels of the United States Camel Corps. Camels and other livestock also disperse the seeds.[1]
The orange-sized fruit is eaten in place by mice, rats, rabbits, hares, squirrels (mostly tree squirrels), and deer, but they do not swallow nor store the seeds. It is eaten less discriminately by domestic horses and mules.[41] The defensive branch spines are too wide spaced to dissuade deer-sized ungulates from eating the leaves, making them only effective against larger animals that do not live in the wild in Texas. Fossils from previous interglacials have been found up to southern Canada, suggesting that its range shrank dramatically after its seed dispersal was diminished.[40][41] Distribution might have been even smaller before the introduction of horses to Texas in the 16th century, even though the wood was favored by many Native American peoples to fashion bows and the local tribes profited greatly from its trade.[41] A close African relative in Gabon is dispersed by forest elephants.[1]
Columbian mammoth, ground sloths,[40] American mastodon, American horses,[41] gomphotheres.[1]
The species largely reproduces asexually, sprouting patches of small, clonal trees that live around 50 years, from a root system that can live tens of thousands. Its sexual reproduction is elaborate but ineffective. The flower mimics carrion or dung (brown color, fetid odor), but it is rarely visited and pollinated by flies. The downward-facing flower is better suited to be pollinated by beetles, as in related species, all of which live in warmer climates. The fruit is similar in taste and nutritious value to cherimoya and it is the largest edible and the most fleshy in the United States. However, the fruiting season is short and the fruit rots soon after falling from the tree; for this reason pawpaw consumption was abandoned when commercial tropical fruits became available. The seeds are large and encased in a sweet, but slippery aril that is difficult to remove. The distribution is very patchy and it is more abundant in floodplains and where it was cared for by indigenous peoples of the Eastern Woodlands. However, the plant grows with no problem in uplands and humans eat the pulp without swallowing the seeds. The seed dispersal capacity of foxes, raccoons, skunks and American black bears is unclear.[1]
American mastodon.[1] Dung beetles could have been the main pollinators before they became rarer after the extinction of the megafauna.[1]
Sticky, repugnant leaves invulnerable to herbivore predation. The fruit divides in two opposite claws when it browns and hardens, the circumference of each being larger than a human leg. Though an obvious zoochoric mechanism, this is far larger than the leg thickness of the largest wild mammals in the area (deer, peccary, coyote), and the seed is mostly dispersed by humans, horses, and cattle. Though already cultivated by Native Americans to make baskets, its range greatly expanded after Europeans introduced livestock, reaching into Louisiana and Iowa by the present day.[1]
Western North America and South America Southeastern United States
Mostly found in disturbed sites and floodplains. Fruit often remains on the branch for months or over a year after ripening, when it is already rotten or desiccated, holding the seeds trapped in its interior. Mammals and birds shun the fruit for its high glycoalkaloid content, which is also lethal to livestock. Reptiles are not affected, and the fruit has features that makes it attractive to turtles (yellow-orange color and right height of fructification), just like other related plants.[1]
The box turtle and gopher tortoise inhabited many areas where wild tomatoes are found, before they went locally extinct.[1] Hesperotestudo.[1]
Large-seeded fruit that takes at least two years to germinate when left on the ground, but only four weeks after being swallowed and dispersed by a captive Galapagos tortoise.
Although the pulp is nutritive and eaten by many animals (even carnivores), the seeds are too large to be swallowed. Zoochory is limited to seeds hoarded by agoutis or eaten by jaguars, but they only do occasionally. Relatives in different latitudes have smaller fruit and seeds, and are eaten by vegetarians. The pulp is soft as to not need chewing, but the seeds are poisonous. Forest elephants feed on plantations in Cameroon.[1][50]
Reaching up to six meters tall, the adults of the giant ground sloth Eremotherium could have gained access to ripe avocados before any other mammal (and juveniles, small enough to climb trees, might have reached higher). The soft, fatty pulp might have made avocados attractive to ground sloths over other fruits, due to their lack of incisors and canines.[1] Cuvieronius, Toxodon, glyptodonts, brontotheres.[1]
Fruit typical of those dispersed by birds and monkeys (bright red, dehiscent, with seeds individually coated with fleshy aril), but slightly larger. Its known assemblage of bird and mammal dispersal agents is anomalously small and the fruit is often found rotting on the ground. The plant sprouts better from larger seeds, yet the seeds better dispersed are the smaller ones ingested by birds.[1]
Fruit eaten by bats but often found felled under the tree; passed over by domestic pigs, horses, and cattle, possibly due to high antibiotic content in the pulp. The seeds of uneaten fruit are killed by weevil larvae.[4]
Fruit the size of a soccer ball, with a hard rind tough to crack. The largest living native mammal, Baird's tapir, cannot open its mouth wide enough to bite it. The only animals witnessed feeding on the fruit are domestic horses, which step on top of it and employ as much as two hundred kilograms pressure to open it. The seeds are rubbery and surrounded by slimy black tissue that is both fetid and sweet. The fruit falls to the ground while still green, and ripens after a month on the forest floor.[1]
American horses.[1] Toxodon was a rhinoceros-sized notoungulate with large, unusually oriented incisors whose function is poorly understood. They could have evolved to peel fruits of this type.[1]
Hard, cylindrical, half-meter long fruit with an inch and a half diameter, containing large seeds 2 centimeters long, 1.5cm wide and 0.5cm thick, embedded in sweet molasses-like pulp. The fruit often remains on the tree long enough for bean weevils and moths to kill the seeds, making it an obvious maladaptation.[1]
Burs stick to the dense hair of horses and cattle, but not to native wild mammals like tapirs, pacas, collared peccaries or white-lipped peccaries. Excluding Pisonia and Krameria, all are herbaceous species that occur on open, well-trampled habitats.[4]
Southern Mexico and the Caribbean to Paraguay and northern Argentina
Large fruit and seeds, with tough epicarp, sticky pulp, and hard endocarp. The fruit grows at heights suitable for terrestrial mammals, but it is often found felled under the tree, uneaten, and accompanied by older, ungerminated seeds. Young trees are heliophilous, requiring the clearing of older trees to grow. Cattle ingest the fruit, dispersing the seeds when they regurgitate them during rumination, and help the establishment of new plants through trampling of older vegetation.[53] Long trunk and leaf spines ill-suited to dissuade smaller predators like rodents.[4]
The flowers grow rapidly into large, fleshy, ear-shaped pods during the dry season of the year after fertilization. The ripe pods are brown and cacao-flavored, and fall to the ground over the space of a month. Though many wild animals eat the pods' flesh, only tapirs are large enough to swallow and disperse the seeds. The pods are eaten and dispersed with ease by domestic horses and cattle, making trees common in pastures or near them.[1][4][54]
American horses, gomphotheres, glyptodonts, ground sloths, Columbian mammoths, and toxodonts.[54]
Thick woody pod with dry sugary pulp and dark color. Though with obvious signs of megafaunal dispersal syndrome, the seeds are dispersed almost exclusively by a seed-hoarding rodent, the agouti.[1]
White, orange-sized fruit. Unless mechanically broken, the seeds die either from desiccation (in a dry environment) or when the pulp ferments (in moist).[1] The fruit is often consumed by free-ranging horses, and the tree's size (3–4 meters tall) and shape is similar to African trees dispersed by megafauna.[4]
Fossils of the native horse Amerhippus have been found in the plant's range area.[4]
Large fruit and seeds, with tough epicarp, sticky pulp and hard endocarp. The fruit grows at heights suitable for terrestrial mammals, but it is often found felled under the tree, uneaten, and accompanied by older, ungerminated seeds. Young trees are heliophilous, requiring the clearing of older trees to grow. Cattle ingest the fruit, dispersing the seeds when they regurgitate them during rumination, and also help the establishment of new plants through trampling of older vegetation.[53]
The wild form measures about ten centimeters. The pulp is soft and does not require chewing, but the seeds are poisonous. Seeds small but clustered at the center, with a pungent, peppery taste. Forest elephants feed on plantations in Cameroon.[40][41]
Large fruit and seeds, with tough epicarp, sticky pulp and hard endocarp. The fruit grows at heights suitable for terrestrial mammals, but it is often found felled under the tree, uneaten, and accompanied by older, ungerminated seeds. Young trees are heliophilous, requiring the clearing of older trees to grow. Cattle ingest the fruit, dispersing the seeds when they regurgitate them during rumination, and also help the establishment of new plants through trampling of older vegetation.[53] Long leaf spines ill-suited to dissuade smaller predators like rodents.[4]
Sweet fruit with hard seeds eaten by domestic horses and cattle. Grows mostly in floodplains and stream margins, in natural corridors followed by livestock herds.[4] The pulp has woody obstacles that prevent mastication.[1]
Eight extinct or endangered species of Hibiscus relatives with evident ornithophilouspollination syndrome, as the flowers produce copious amounts of nectar but remain folded in a tube that make it only accessible to a few bird species.[66]
"Remarkable similarity" between the flower's corolla and the bill curvature of recently extinct Hawaii mamo and lesser ʻakialoa.[66]
A relative of Gymnocladus and Gleditsia that also fails to propagate naturally due to the hard seed coat that is impenetrable to water.[67] Seeds are presumably viable after passing through an animal's digestive track, but require treatment with acid or hot water to encourage artificial germination.[68] Similar, related species are dispersed by megafaunal animals or thought to have evolved alongside now-extinct megafauna which they presumably benefited from.[69]
Inability to regenerate in either the deep shade of a forest canopy or under heavy browsing in the open. Though some Eurasian megafauna capable of clearing forests survived into the Holocene (red deer, aurochs, tarpan, wisent, Eurasian beaver and wild boar), differences in the composition of pollen records between the earliest Holocene previous to large human-induced clearing and the interglacial MIS 5 suggests that further clearing was done by even larger megaherbivores that disappeared in the Late Pleistocene.[70]
Reduction of fossil pollen concentration in Ireland and subsequent increase unrelated to climate change.[70]
The giant deer Megaloceros colonized Ireland right around the time juniper numbers went down and became extinct when they went up.[70]Megaloceros browsed juniper and other shrubs because of their high phosphorus content, which it needed to grow antlers for the mating season.[72] This predation caused in turn the descent of juniper and its replacement by grasses.[70]
Endemic shrub in geographical and genetic decline due to the lack of seed dispersal on the island. Most plants grow in the vicinity of their parents causing inbreeding.[73][74]
Lilford's wall lizard was widespread in Mallorca and Menorca before Roman colonization, when it was wiped out by introduced mammalian predators. It survives in uninhabited islets around both islands and is the only animal observed ingesting the fruit and dropping the seeds in places suitable for plant establishment.[73]
Leaves with defensive spiny edges up to four or five meters over the ground, when they are replaced by smooth leaves.[1] This is more than twice the reach of the current largest browsers in the area, the red deer and the wisent.
Dry but botanically diverse biome, consisting of grasses, forbs and sedges, which occupied most of northern Eurasia and North America during the Pleistocene and was associated with high concentrations of large grazers. Starting about 13,000 years ago, the steppe was replaced by wet moss and shrub tundra, taiga and deciduous forests with reduced plant diversity. The change has been traditionally attributed to a climatic shift to warmer, wetter, less continental conditions in the transition to the Holocene, and in turn used to explain the extinction of the megafauna. Sergey Zimov proposed the opposite: That the extinction of the megafauna caused the change in vegetation, and that this would not have happened if the megafauna survived, as was the case in previous interglacials.[70]
Inability to regenerate in either the deep shade of a forest canopy or under heavy browsing in the open. Though some megafauna capable of clearing forests survived into the Holocene, differences in the composition of pollen records between the earliest Holocene and the MIS 5 suggests that further clearing was done by larger megaherbivores in the Pleistocene.[70] Furthermore, oak is often positively associated with thorny shrub, benefiting from associational resistance. The oak sapling profits from the thorn protecting the shrub, but also from sufficient light availability in contrast to closed forest.[77]
Hippopotamus, straight-tusked elephant, and narrow-nosed rhinoceros.[70][71]
Native dung fly dependent on domestic cattle, and before cattle was introduced, on human dung. The flies ignore kangaroo dung because it is drier and not as abundant.[26]
Flocks follow horse and cattle herds, feeding on insects stirred up by trampling. Their numbers and eastern range expanded greatly after livestock was introduced by Europeans; however, fossils evidence that they were just as numerous or more in the Pleistocene, and also that there were two other species in North America that disappeared during the transition to the Holocene.[78]
Critically endangered, the condor survives in a few areas near the Pacific coast. However, the same species was present in most of North America before the human settlement of the Americas, and a close relative was found in Cuba. It benefited from the introduction of livestock by Europeans, incorporating horse, cattle, and sheep into its diet, and even expanded its Holocene range before human-induced habitat loss, lead[79] and DDT poisoning,[80][81] and poaching[82] drove it to near extinction by 1987.[83] Cattle bones were the most commonly found in condor nests by 2000.[84]
It was suggested that condors survived near the Pacific by feeding on salmon, beached whales, elephant seal and mule deer carcasses, which have skin soft enough to be pierced by the condor's weak beak. Elsewhere, the condor would have fed on terrestrial megafauna, but only after larger carrion birds like Teratornis had pierced the tougher furry skin, mirroring the symbiotic relationship between African white-backed vultures and the larger lappet-faced vultures and white-headed vultures.[1][84]
Discovered in 1873 living among, and feeding on seabird colonies in small, rocky islets denuded of vegetation. However, the species was noted to have a powerful prehensile tail, long fingers typical of skinks that live in the lower canopy, vegetarian dentition, and favored vegetation and fruit while in captivity. The lower eyelid had a unique transparent "window" that allowed animals to receive information from below while asleep.[85]
Subfossil remains and historical records indicate that the species was also present until recently in São Vicente and Santa Luzia islands, and that all were united into a single, more forested island during the Pleistocene.[86] The "window" could be an adaptation against predators striking from below while the crepuscular skink slept on branches during the day.[85] This was ineffective against the only known natural predator in modern times, the barn owl.[86]
Critically endangered species that was once widespread through Cuba, the Cayman Islands, and the Bahamas. One of the smallest crocodiles but also among the most terrestrial and intelligent; observations in captivity revealed previously unknown pack-hunting behavior, which would make it capable of taking down animals larger than those found in the Caribbean.[87]
Though normally solitary, adult males were observed banding together and cooperating to hunt sifaka, a tree-dwelling lemur smaller than a fossa, and thus unable to feed the group.[88]
The behavior could have evolved to hunt larger arboreal lemurs like the extinct sloth lemurs, though alternative explanations have been offered.[88]
The largest and rarest of Madagascar dung beetles, apparently entirely dependent on human feces. Yet humans arrived for the first time only 2000 years ago.[89]
Both species follow cattle in Brazil (mostly zebu-crossed Brahman, which are bigger fruit eaters) and extract partially digested seeds from their dung. They have adaptations to terrestrial locomotion not present in other macaws, and they ignore the same fruit while on the tree, even ripe, suggesting that this behavior is an ancient adaptation rather than recently learned. Grey parrots do the same with dung of African forest elephants.[53]
Stegodon florensis,[90] a dwarf proboscidean of similar size to bovines, horses, and large pigs.
More recently, it was suggested that the Komodo dragon's ancestors evolved their size in northern Australia and spread north to colonize Indonesia.[91] This would make the Komodo dragon a double anachronism, as they would have originally preyed on giant marsupials like Diprotodon. Pigs, cattle, deer, camels, horses, and buffaloes were later introduced to Australia, where they have no predators and are overpopulated; it was suggested to introduce Komodo dragons as a natural predator to control their population[92]
Although the species became extinct in the wild over one thousand years ago, the animals become cautious when exposed to images or recordings of tigers. Exposition to other animals does not elicit the same response or not as strong.[94]
Capable of sustaining speeds of 60 miles per hour, making it the second fastest land animal in the world after the cheetah, and the fastest long-endurance runner. No predator in its range approaches this speed. Cougars are the only regular predators of adult pronghorns, but can only hunt them when the terrain allows for a stealthy approach. Wolves and coyotes may prey on the young but are poorly suited to hunt adults. American black bears have been observed attempting ambushes on occasion, but typically unsuccessfully.[10] The leg muscles are so overbuilt towards sustained speed that pronghorns cannot jump and will try to cross fences by going under rather than above.[1]
The jaguar was present in large areas of the United States during the Pleistocene and might have hunted pronghorns by stealth, just like the cougar.[10]
The extinct American cheetahs (Miracinonyx inexpectatus and particularly M. trumani) were explosive runners very similar to the living cheetah, though not closely related to it. If they could reach the same speed (70mph), they would have been the most successful predators of pronghorns in short distances, and also explain the pronghorn's evolution towards sustained running, since modern cheetahs cannot keep running for long.[10]
Chasmaporthetes, the only hyena that ever colonized North America successfully, had cheetah-like proportions and was better built for speed than its living relatives.[10]
The phenomenon was referenced (though not by name) in the 1259 issue "Bee Orchid" of the online comic strip xkcd by Randall Munroe, published on September 2, 2013. In the comic, it is claimed that the orchid Ophrys apifera mimics the female of a bee species to attract males and ensure pollination, but that the bee is extinct and the orchid is doomed to follow, only delaying it by resorting to less effective self-pollination. In reality, only the first part is true: the flower mimics a bee, and reproduces exclusively by self-pollination in northern Europe, but it is pollinated successfully by bees of the genus Eucera in the Mediterranean region.[97]
The Holocene extinction, or Anthropocene extinction, is the ongoing extinction event caused by humans during the Holocene epoch. These extinctions span numerous families of plants and animals, including mammals, birds, reptiles, amphibians, fish, and invertebrates, and affecting not just terrestrial species but also large sectors of marine life. With widespread degradation of biodiversity hotspots, such as coral reefs and rainforests, as well as other areas, the vast majority of these extinctions are thought to be undocumented, as the species are undiscovered at the time of their extinction, which goes unrecorded. The current rate of extinction of species is estimated at 100 to 1,000 times higher than natural background extinction rates and is increasing. During the past 100–200 years, biodiversity loss and species extinction have accelerated, to the point that most conservation biologists now believe that human activity has either produced a period of mass extinction, or is on the cusp of doing so. As such, after the "Big Five" mass extinctions, the Holocene extinction event has also been referred to as the sixth mass extinction or sixth extinction; given the recent recognition of the Capitanian mass extinction, the term seventh mass extinction has also been proposed for the Holocene extinction event.
Asimina is a genus of small trees or shrubs described as a genus in 1763. Asimina is the only temperate genus in the tropical and subtropical flowering plant family Annonaceae. Asimina have large, simple leaves and large fruit. It is native to eastern North America and collectively referred to as pawpaw. The genus includes the widespread common pawpaw Asimina triloba, which bears the largest edible fruit indigenous to the United States. Pawpaws are native to 26 states of the U.S. and to Ontario in Canada. The common pawpaw is a patch-forming (clonal) understory tree found in well-drained, deep, fertile bottomland and hilly upland habitat. Pawpaws are in the same plant family (Annonaceae) as the custard apple, cherimoya, sweetsop, soursop, and ylang-ylang; the genus is the only member of that family not confined to the tropics. Fossils date to the Cretaceous.
Maclura pomifera, commonly known as the Osage orange, is a small deciduous tree or large shrub, native to the south-central United States. It typically grows about 8 to 15 metres (30–50 ft) tall. The distinctive fruit, a multiple fruit, is roughly spherical, bumpy, 8 to 15 centimetres (3–6 in) in diameter, and turns bright yellow-green in the fall. The fruits secrete a sticky white latex when cut or damaged. Despite the name "Osage orange", it is not related to the orange. It is a member of the mulberry family, Moraceae. Due to its latex secretions and woody pulp, the fruit is typically not eaten by humans and rarely by foraging animals. Ecologists Daniel H. Janzen and Paul S. Martin proposed in 1982 that the fruit of this species might be an example of what has come to be called an evolutionary anachronism—that is, a fruit coevolved with a large animal seed dispersal partner that is now extinct. This hypothesis is controversial.
In zoology, megafauna are large animals. The precise definition of the term varies widely, though a common threshold is approximately 45 kilograms (99 lb), with other thresholds as low as 10 kilograms (22 lb) or as high as 1,000 kilograms (2,200 lb). Large body size is generally associated with other traits, such as having a slow rate of reproduction and in large herbivores, reduced or negligible adult mortality from being killed by predators.
A frugivore is an animal that thrives mostly on raw fruits or succulent fruit-like produce of plants such as roots, shoots, nuts and seeds. Approximately 20% of mammalian herbivores eat fruit. Frugivores are highly dependent on the abundance and nutritional composition of fruits. Frugivores can benefit or hinder fruit-producing plants by either dispersing or destroying their seeds through digestion. When both the fruit-producing plant and the frugivore benefit by fruit-eating behavior the interaction is a form of mutualism.
The term Australian megafauna refers to the megafauna in Australia during the Pleistocene Epoch. Most of these species became extinct during the latter half of the Pleistocene, and the roles of human and climatic factors in their extinction are contested.
Daniel Hunt Janzen is an American evolutionary ecologist and conservationist. He divides his time between his professorship in biology at the University of Pennsylvania, where he is the DiMaura Professor of Conservation Biology, and his research and field work in Costa Rica.
In spermatophyte plants, seed dispersal is the movement, spread or transport of seeds away from the parent plant. Plants have limited mobility and rely upon a variety of dispersal vectors to transport their seeds, including both abiotic vectors, such as the wind, and living (biotic) vectors such as birds. Seeds can be dispersed away from the parent plant individually or collectively, as well as dispersed in both space and time. The patterns of seed dispersal are determined in large part by the dispersal mechanism and this has important implications for the demographic and genetic structure of plant populations, as well as migration patterns and species interactions. There are five main modes of seed dispersal: gravity, wind, ballistic, water, and by animals. Some plants are serotinous and only disperse their seeds in response to an environmental stimulus. These modes are typically inferred based on adaptations, such as wings or fleshy fruit. However, this simplified view may ignore complexity in dispersal. Plants can disperse via modes without possessing the typical associated adaptations and plant traits may be multifunctional.
The Late Pleistocene is an unofficial age in the international geologic timescale in chronostratigraphy, also known as the Upper Pleistocene from a stratigraphic perspective. It is intended to be the fourth division of the Pleistocene Epoch within the ongoing Quaternary Period. It is currently defined as the time between c. 129,000 and c. 11,700 years ago. The late Pleistocene equates to the proposed Tarantian Age of the geologic time scale, preceded by the officially ratified Chibanian. The beginning of the Late Pleistocene is the transition between the end of the Penultimate Glacial Period and the beginning of the Last Interglacial around 130,000 years ago. The Late Pleistocene ends with the termination of the Younger Dryas, some 11,700 years ago when the Holocene Epoch began.
Asimina triloba, the American papaw, pawpaw, paw paw, or paw-paw, among many regional names, is a small deciduous tree native to the eastern United States and southern Ontario, Canada, producing a large, yellowish-green to brown fruit. Asimina is the only temperate genus in the tropical and subtropical flowering plant family Annonaceae, and Asimina triloba has the most northern range of all. Well-known tropical fruits of different genera in family Annonaceae include the custard-apple, cherimoya, sweetsop, ylang-ylang, and soursop.
Crescentia alata, variously called Mexican calabash, jícaro, morro, morrito, or winged calabash, is a plant species in the family Bignoniaceae and in the genus Crescentia, native to southern Mexico and Central America south to Costa Rica.
Cucumis humifructus, the aardvark cucumber or aardvark pumpkin, is a kind of cucumber from southern Africa, tropical Africa, and Madagascar which fruits underground. It is a prostrate vine up to seven meters in length. It is reliant on the aardvark to eat the fruit in order to spread and re-bury the seeds of the plant. The species was described in 1927, with the name spelled C. humofructus, but this is corrected to C. humifructus following the International Code of Nomenclature for algae, fungi, and plants.
Cuvieronius is an extinct New World genus of gomphothere which ranged from southern North America to western South America during the Pleistocene epoch. Among the last gomphotheres, it became extinct at the end of the Pleistocene, approximately 12,000 years ago, following the arrival of humans to the Americas.
Attalea is a large genus of palms native to Mexico, the Caribbean, Central and South America. This pinnately-leaved, non-spiny genus includes both small palms lacking an aboveground stem and large trees. The genus has a complicated taxonomic history, and has often been split into four or five genera based on differences in the male flowers. Since the genera can only be distinguished on the basis of their male flowers, the existence of intermediate flower types and the existence of hybrids between different genera has been used as an argument for keeping them all in the same genus. This has been supported by recent molecular phylogenies.
Pleistocene rewilding is the advocacy of the reintroduction of extant Pleistocene megafauna, or the close ecological equivalents of extinct megafauna. It is an extension of the conservation practice of rewilding, which aims to restore functioning, self-sustaining ecosystems through practices that may include species reintroductions.
Quaternary science is the subfield of geology which studies the Quaternary Period commonly known as the ice age. The Quaternary Period is a time period that started around 2.58 million years ago and continues today. This period is divided into two epochs – the Pleistocene Epoch and the Holocene Epoch. The aim of Quaternary science is to understand everything that happened during the Pleistocene Epoch and the Holocene Epoch to be able to acquire fundamental knowledge about Earth's environment, ecosystem, climate changes, etc. Quaternary science was first studied during the nineteenth century by Georges Cuvier, a French scientist. Most Quaternary scientists have studied the history of the Quaternary to predict future changes in climate.
The Late Pleistocene to the beginning of the Holocene saw the extinction of the majority of the world's megafauna, which resulted in a collapse in faunal density and diversity across the globe. The extinctions during the Late Pleistocene are differentiated from previous extinctions by its extreme size bias towards large animals, and widespread absence of ecological succession to replace these extinct megafaunal species, and the regime shift of previously established faunal relationships and habitats as a consequence. The timing and severity of the extinctions varied by region and are thought to have been driven by varying combinations of human and climatic factors. Human impact on megafauna populations is thought to have been driven by hunting ("overkill"), as well as possibly environmental alteration. The relative importance of human vs climatic factors in the extinctions has been the subject of long-running controversy.
Paul Schultz Martin was an American geoscientist at the University of Arizona who developed the theory that the Pleistocene extinction of large mammals worldwide was caused by overhunting by humans. Martin's work bridged the fields of ecology, anthropology, geosciences, and paleontology.
Mauro Galetti. is a Brazilian ecologist and conservation biologist. He is a full professor in the Department of Biodiversity at the Universidade Estadual Paulista, Rio Claro, São Paulo and has worked at Stanford University (USA), Aarhus University (Denmark) and the University of Miami (USA). He also holds a position as a Courtesy Associated Professor at Florida International University, Miami, FL. Galetti's work has centered on the analysis of the ecological and evolutionary consequences of defaunation. He was awarded by WWF in 1998 and was a Tinker Fellow at Stanford University and a visiting professor at Aarhus Universitet, Denmark in 2017.
The wood-pasture hypothesis is a scientific hypothesis positing that open and semi-open pastures and wood-pastures formed the predominant type of landscape in post-glacial temperate Europe, rather than the common belief of primeval forests. The hypothesis proposes that such a landscape would be formed and maintained by large wild herbivores. Although others, including landscape ecologist Oliver Rackham, had previously expressed similar ideas, it was the Dutch researcher Frans Vera, who, in his 2000 book Grazing Ecology and Forest History, first developed a comprehensive framework for such ideas and formulated them into a theorem. Vera's proposals, although highly controversial, came at a time when the role grazers played in woodlands was increasingly being reconsidered, and are credited for ushering in a period of increased reassessment and interdisciplinary research in European conservation theory and practice. Although Vera largely focused his research on the European situation, his findings could also be applied to other temperate ecological regions worldwide, especially the broadleaved ones.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Cheke, A. & Hume, J.P. (2009) Lost land of the dodo: The ecological history of Mauritius, Réunion and Rodrigues. T & AD Poyser, London, 480 pages.
1 2 3 4 5 Jackson, P.S.W.; Cronk, Q.C.B.; Parnell, J.A.N. (1988). "Notes on the regeneration of two rare Mauritian endemic trees". Tropical Ecology (78): 56–65.
1 2 3 4 5 6 7 8 9 10 11 12 13 Godfrey, Laurie R.; Jungers, William L.; Schwartz, Gary T.; Irwin, Mitchell T. (2008). "Ghosts and Orphans". Elwyn Simons: A Search for Origins. Developments in Primatology: Progress and Prospects. New York, NY: Springer New York. pp.361–395. doi:10.1007/978-0-387-73896-3_24. ISBN978-0-387-73895-6.
1 2 3 Bellot, Sidonie, et al. "On the origin of giant seeds: the macroevolution of the double coconut (Lodoicea maldivica) and its relatives (Borasseae, Arecaceae)." New Phytologist 228.3 (2020): 1134-1148.
↑ Pynee, K. B., Lorence, D. H., & Khurun, P. (2018). Conservation status of Mascarene Amaranth Aerva congesta Balf. F. Ex Baker (Eudicots: Caryophyllales: Amaranthaceae): a Critically Endangered endemic herb of the Mascarenes, Indian Ocean. Journal of Threatened Taxa, 10(8), 12056-12063.
↑ Rawlence, N. J., and A. Cooper. "Youngest reported radiocarbon age of a moa (Aves: Dinornithiformes) dated from a natural site in New Zealand." Journal of the Royal Society of New Zealand 43.2 (2013): 100-107.
↑ Wood, J. R., Wilmshurst, J. M., Worthy, T. H., Holzapfel, A. S., & Cooper, A. (2012). A lost link between a flightless parrot and a parasitic plant and the potential role of coprolites in conservation paleobiology. Conservation Biology, 26(6), 1091-1099.
↑ Orihuela, J., Viñola, L. W., Vázquez, O. J., Mychajliw, A. M., de Lara, O. H., Lorenzo, L., & Soto-Centeno, J. A. (2020). Assessing the role of humans in Greater Antillean land vertebrate extinctions: New insights from Cuba. Quaternary Science Reviews, 249, 106597.
↑ Worthy, T. H. (2000). The fossil megapodes (Aves: Megapodiidae) of Fiji with descriptions of a new genus and two new species. Journal of the Royal Society of New Zealand, 30(4), 337-364.
1 2 Givnish, T. J.; K. J. Sytsma; J. F. Smith; W. S. Hahn (1995). "Molecular evolution, adaptive radiation, and geographic speciation in Cyanea (Campanulaceae, Lobelioideae)". In W. L. Wagner and V. Funk (ed.). Hawaiian Biogeography: Evolution on a Hot-Spot Archipelago. Washington, D. C.: Smithsonian Institution. pp. 288–337.
1 2 Champion, S. J. (2020). Biogeography and Phylogenetics of the Hawaiian Endemic Hibiscadelphus, Hau Kuahiwi (Malvaceae) (Doctoral dissertation, University of Hawai'i at Manoa).
1 2 Traveset, A., & Riera, N. (2005) Disruption of a plant‐lizard seed dispersal system and its ecological effects on a threatened endemic plant in the Balearic Islands. Conservation Biology, 19(2), 421-431.
↑ Calviño‐Cancela, M., et al. (2012) The role of seed dispersal, pollination and historical effects on genetic patterns of an insular plant that has lost its only seed disperser. Journal of Biogeography, 39(11), 1996-2006.
1 2 Mateo, J. A., Barone, R., Hernández-Acosta, C. N., & López-Jurado, L. F. (2020) La muerte anunciada de dos gigantes macaronésicos: el gran escinco caboverdiano, Chioninia coctei (Duméril & Bibron, 1839) y el lagarto de Salmor, Gallotia simonyi (Steindachner, 1889). Bol. Asoc. Herpetol. Esp. Vol. 31 (2), pgs. 3-30.
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Extent of the Afrotropical biogeographical realm
African bush elephant feeding on a tree with defensive spines
Restoration of a saddle-backed Mauritius giant tortoise herd
Living dodo depicted c. 1625
