The end of existence of a group of organisms, caused by their inability to adapt to changing environmental conditions. 7 Animals that has Gone Extinct in Human History is influenced by both evolution, which allows organisms to adapt, and extinction.
Extinction affects individual species—that is, groups of interbreeding organisms—as well as collections of related species, such as members of the same family, order, or class.
7. PASSENGER PIGEON
The passenger pigeon or wild pigeon is an extinct species of pigeon that was endemic to North America. Its common name is derived from the French word passager, meaning “passing by”, due to the migratory habits of the species. The scientific name also refers to its migratory characteristics. The morphologically similar mourning dove was long thought to be its closest relative, and the two were at times confused, but genetic analysis has shown that the genus Patagioenas is more closely related to it than the Zenaida doves.
The pigeon migrated in enormous flocks, constantly searching for food, shelter, and breeding grounds, and was once the most abundant bird in North America, numbering around 3 to 5 billion at the height of its population. It was not always as abundant, and the population size fluctuated rapidly over time. A very fast flyer, it could reach 100 km/h (62 mph). The bird fed mainly on mast, and also fruits and invertebrates.
Passenger pigeons were hunted by Native Americans, but hunting intensified after the arrival of Europeans, particularly in the 19th century. Pigeon meat was commercialized as cheap food, resulting in hunting on a massive scale for many decades. There were several other factors contributing to the decline and subsequent extinction of the species, including shrinking of the large breeding populations necessary for preservation of the species and widespread deforestation, which destroyed its habitat.
Martha, thought to be the last passenger pigeon, died on September 1, 1914, at the Cincinnati Zoo. The eradication of this species is a notable example of anthropogenic extinction.
6. WEST AFRICAN BLACK RHINOCEROS
The western black rhinoceros (Diceros bicornis longipes) or West African black rhinoceros is a subspecies of the black rhinoceros, declared extinct by the IUCN in 2011. The western black rhinoceros was believed to have been genetically different from other rhino subspecies. It was once widespread in the savanna of sub-Saharan Africa, but its numbers declined due to poaching. The western black rhinoceros resided primarily in Cameroon, but surveys since 2006 have failed to locate any individuals.
The population was first discovered in Southwest Chad, Central African Republic (CAR), North Cameroon, and Northeast Nigeria.
The western black rhinoceros is one of three subspecies of the black rhinoceros to become extinct in historical times, the other two being the southern black rhinoceros and the north-eastern black rhinoceros.
The western black rhinoceros was heavily hunted in the beginning of the 20th century, but the population rose in the 1930s after preservation actions were taken. As protection efforts declined over the years, so did the number of western black rhinos. By 1980 the population was in the hundreds. No animals are known to be held in captivity, however it was believed in 1988 that approximately 20–30 were being kept for breeding purposes. Poaching continued and by 2000 only an estimated 10 survived.
In 2001, this number dwindled to only five. While it was believed that around thirty still existed in 2004, this was later found to be based upon falsified data. Widespread poaching is concluded to be partly responsible for bringing the species close to extinction, along with farmers killing rhinos to defend their crops in areas close to rhino territories, and trophy hunting. By 1995 the number of western black rhinos had dropped to 2,500 individuals. The sub-species was declared officially extinct in 2011, with its last sighting reported in 2006 in Cameroon’s Northern Province.
5. SEA MINK
The sea mink (Neovison macrodon) is an extinct species of carnivore from the eastern coast of North America in the family Mustelidae, the largest family in the order Carnivora. It was most closely related to the American mink (Neovison vison), however it is debated whether or not the sea mink was a subspecies of the American mink (making it Neovison vison macrodon) or a species of its own. Distinctions made between the two minks is that the sea mink was larger and had redder fur.
In fact, the justification for it being its own species is the size difference between it and the American mink. However, the sea mink was first described in 1903 after its extinction, so information regarding its external appearances and behaviors all stem from speculation and accounts made by fur traders and Native Americans. It was found on the New England coast and the Maritime Provinces, though its range may have stretched further south during the last glacial period. Conversely, its range may have been restricted to solely the New England coast, specifically the Gulf of Maine, or just islands off of it. As it was the largest of the minks, they were more desirable to hunt by fur traders than other mink species, and became extinct sometime in the late 1800s.
The sea mink was pursued by fur traders due to their larger size which made them more desirable than other mink species further inland. The unregulated trade eventually led to their extinction, which is thought to have occurred anywhere from 1860 to 1920. The sea mink was seldom sighted in the years proceeding 1860, with the last recorded kill of a sea mink in Maine made in 1880 near Jonesport, and the last known kill made in Campobello Island in New Brunswick in 1894. However, the kill made in 1894 and 1880 are speculated to be large American minks. Fur traders made traps to catch sea minks and also pursued them with dogs. If a sea mink were to escape into a small hole on the rocky ledges, they were dug out by hunters using shovels and crowbars.
4. TECOPA PUPFISH
The Tecopa pupfish is member of the genus Cyprinodon of the pupfish family Cyprinodontidae, a taxon of killifish most diverse in North America.
The Tecopa pupfish (Cyprinodon nevadensis calidae) is an extinct subspecies of the Amargosa pupfish (Cyprinodon nevadensis). The small, heat-tolerant pupfish was endemic to the outflows of a pair of hot springs in the Mojave Desert of California. Habitat modifications and the introduction of non-native species led to its extinction in about 1970.
The fish were about 1–1.5 inches (2.5–4 cm) in length.
The dorsal fin was positioned closer to the tail than the head. The pelvic fin was small or sometimes absent, and had six lepidotrichia. Similar to some other Cyprinodons, breeding males displayed a bright blue coloration. Females had between six and ten vertical stripes. In 1966, Miller found that the population at Tecopa Hot Springs was nearly extinct. A population was found at a reservoir at a nearby motel two years later, but its smaller scales suggested that it may have already hybridized with the Amargosa River pupfish. In 1970, concerns over this habitat alteration and the presence of non-native species such as the bluegill and the western mosquitofish led to its inclusion in both Federal and California lists of endangered species.
The last confirmed specimens of C. n. calidae were collected on February 2, 1970, and the subspecies was probably extinct by the next year. Further surveys in 1972 and 1977 returned no examples of the fish. In 1978, United States Fish and Wildlife Service announced that it was considering delisting the fish, with Assistant Secretary of the Interior Robert L. Herbst calling the loss “totally avoidable” and saying, “The human projects which so disrupted its habitat, if carefully planned, could have ensured its survival.” In 1981, after an exhaustive search of over 40 locations, the Fish and Wildlife Service officially declared the fish extinct. It was the first animal removed from the provisions of the 1973 Endangered Species Act as a result of its extinction.
3. PYRENEAN IBEX
The Pyrenean ibex (Capra pyrenaica pyrenaica), Spanish common name bucardo, was one of the four subspecies of the Spanish ibex or Iberian wild goat, a species endemic to the Iberian Peninsula. Pyrenean ibex were most common in the Cantabrian Mountains, Southern France, and the northern Pyrenees. This species was common during the Holocene and Upper Pleistocene, during which their morphology, primarily some skulls, of the Pyrenean ibex was found to be larger than other Capra subspecies in southwestern Europe from the same time.
Following several failed attempts to revive the subspecies through cloning, a living specimen was born in 2003. However, this victory was short lived, as the specimen died several minutes later due to a lung defect. The Pyrenean ibex had short hair which varied according to seasons. During the summer, its hair was short, and in winter, the hair grew longer and thicker. The hair on the ibex’s neck remained long through all seasons. Male and female ibex could be distinguished due to color, fur, and horn differences. The male was a faded grayish brown during the summer, and they were decorated with black in several places on the body such as the mane, forelegs, and forehead. In the winter, the ibex was less colorful.
The male transformed from a greyish brown to a dull grey and where the spots were once black, it became dull and faded. The female ibex, though, could be mistaken for a deer since its coat was brown throughout the summer. Unlike the male ibex, a female lacked black coloring. Young ibex were colored like the female for the first year of life.
The Pyrenean ibex was one of four subspecies of the Iberian ibex. The first to become extinct was the Portuguese ibex (Capra pyrenaica lusitanica) in 1892. The Pyrenean ibex was the second, with the last individual, a female called Celia, found dead in 2000.
In the middle Ages, Pyrenean ibex were very abundant in the Pyrenees region, but decreased rapidly in the 19th and 20th centuries due to hunting pressure. In the second half of the 20th century, only a small population survived in the Ordesa National Park situated in the Spanish Central Pyrenees.
Competition with domestic and wild ungulates also contributed to the extinction of the Pyrenean ibex. Much of its range was shared with sheep, domestic goats, cattle, and horses, especially in summer when it was in the high mountain pastures. The last natural Pyrenean ibex, a female named Celia, was found dead on January 6, 2000. Although her cause of death is known (she was killed by a fallen tree), the reason for the extinction of the subspecies as a whole is a mystery. Some hypotheses include the inability to compete with other species for food, infections and diseases, and poaching.
The Pyrenean ibex became the first taxon ever to become “unextinct” on July 30, 2003, when a cloned female ibex was born alive and survived for several minutes, before dying from lung defects.
The quagga (Equus quagga quagga) is an extinct subspecies of plains zebra that lived in South Africa until the 19th century. It was long thought to be a distinct species, but genetic studies have shown it to be the southernmost subspecies of plains zebra. It is considered particularly close to Burchell’s zebra. Its name was derived from its call, which sounded like “kwa-ha-ha”.
The name “quagga” is derived from the Khoikhoi word for zebra and is onomatopoeic, being said to resemble the quagga’s call, variously transcribed as “kwa-ha-ha”, “kwahaah”, or “oug-ga”. The name is still used colloquially for the plains zebra. The quagga was the first extinct animal to have its DNA analysed, and this 1984 study launched the field of ancient DNA analysis.
It confirmed that the quagga was more closely related to zebras than to horses, with the quagga and mountain zebra (Equus zebra) sharing an ancestor 3–4 million years ago. An immunological study published the following year found the quagga to be closest to the plains zebra. A 1987 study suggested that the mtDNA of the quagga diverged at a range of roughly 2% per million years, similar to other mammal species, and again confirmed the close relation to the plains zebra.
The quagga is believed to have been 257 cm (8 ft 5 in) long and 125–135 cm (4 ft 1 in–4 ft 5 in) tall at the shoulder. Its coat pattern was unique among equids: zebra-like in the front but more like a horse in the rear. It had brown and white stripes on the head and neck, brown upper parts and a white belly, tail and legs.
As it was easy to find and kill, the quagga was hunted by early Dutch settlers and later by Afrikaners to provide meat or for their skins. The skins were traded or used locally. The quagga was probably vulnerable to extinction due to its limited distribution, and it may have competed with domestic livestock for forage. The quagga had disappeared from much of its range by the 1850s. The last population in the wild, in the Orange Free State, was extirpated in the late 1870s. The last known wild individual died in 1878.
The extinction of the quagga was internationally accepted by the 1900 Convention for the Preservation of Wild Animals, Birds and Fish in Africa. The last specimen was featured on a Dutch stamp in 1988. There are 23 known stuffed and mounted quagga specimens throughout the world. In addition, there is a mounted head and neck, a foot, seven complete skeletons, and samples of various tissues. A twenty-fourth mounted specimen was destroyed in Königsberg, Germany, during World War II.
1. TASMANIAN TIGER
The thylacine was the largest known carnivorous marsupial of modern times. It is commonly known as the Tasmanian tiger (because of its striped lower back) or the Tasmanian wolf. Native to continental Australia, Tasmania and New Guinea, it is believed to have become extinct in the 20th century. It was the last extant member of its family, Thylacinidae; specimens of other members of the family have been found in the fossil record dating back to the late Oligocene.
They are easy to tell from a true dog because of the stripes on the back but the skeleton is harder to distinguish. Zoology students at Oxford had to identify 100 zoological specimens as part of the final exam. Word soon got around that, if ever a ‘dog’ skull was given; it was safe to identify it as Thylacinus on the grounds that anything as obvious as a dog skull had to be a catch.
The thylacine held the title of Australia’s largest predator until about 3500 years ago. The thylacine resembled a large, short-haired dog with a stiff tail which smoothly extended from the body in a way similar to that of a kangaroo. Many European settlers drew direct comparisons with the hyena, because of its unusual stance and general demeanor. Its yellow-brown coat featured 13 to 21 distinctive dark stripes across its back, rump and the base of its tail, which earned the animal the nickname “tiger”.
The thylacine had become extremely rare or extinct on the Australian mainland before British settlement of the continent, but it survived on the island of Tasmania along with several other endemic species, including the Tasmanian devil. Intensive hunting encouraged by bounties is generally blamed for its extinction, but other contributing factors may have been disease, the introduction of dogs, and human encroachment into its habitat. Despite its official classification as extinct, sightings are still reported, though none has been conclusively proven.