Speciation, the evolution of biological species, and extinction, the end of biological species, are important attributes of the ecology. The term extinction, in ecology, refers to the end of a specific group of taxa. In simple words, the death of the last individual of a particular species is considered to be the moment of extinction of that species. Over the years, the planet has witnessed the extinction of several species of animals, ranging from dinosaurs to frogs. Some were mass extinctions, while the others were virtually brought to the brink of extinction by human activities, before they were completely wiped off. This may come in as a surprise for many, but over the last 100 years alone, several

animal species

have become extinct. Before we begin with the list of extinct animals in the last 100 years, let's have a look at the various causes which led to extinction of these animals featuring in IUCN (International Union for Conservation of Nature) extinct animals list over the last few decades.

Extinction of Animals Causes

There are several causes of extinction of several animal species, prominent among which are loss of habitat, global warming and hunting. Let's take a detailed look at these prominent causes of animal extinction.

Extinction of Animals Due to Deforestation

: Species-area math states that a non-linear relationship exists between the land area and the number of species residing in that area, which means lower the area, lesser the species and vice versa.

Deforestation

has caused the green zones of the planet to shrink, which has resulted in loss of habitat for several animal species. Some species have to venture out of their demarcated zones in search of food, which makes them more vulnerable to a life threatening conflict with the mankind, while the others are wiped off owing to the extinction of a particular species on whom they had been dependent for food.

Extinction of Animals Due to Global Warming

: Scientists estimate that around 70 species of frogs have been wiped off the planet due to

climate change

. This is just the tip of the iceberg considering that approximately 100 to 200 species of animals, including

penguins

and

polar bears

, have become more vulnerable to extinction, owing to this increase in global temperature. Extinction of animals due to

global warming

is a serious issue, which is just going to get more serious with time.

Extinction of Animals Due to Hunting

: The first name that comes to our mind when we hear the phrase 'extinction of animals due to hunting' is dodo. Extensive

hunting

of this flightless bird led to its extinction by mid 17th century. Early man hunted animals for food and though rarely, to protect himself. Today we see a more grievous picture of hunting, referred to as poaching, an attribute of

animal cruelty

wherein animals are hunted for economic gains. Various species, including

cheetahs

, tigers and elephants, have been extensively poached owing to the high demand for various animal products in the international market.

Other than these predation, diseases, competition, genetics and demographic phenomena also play a significant role in the extinction of several species from the planet.

List of Extinct Animals in the Last 100 Years

The long list of

extinct animals

in the world features more than 50 animal species that have become extinct from the planet in last 100 years alone. This extinct animals list feature mammals, birds, reptiles as well as amphibians.

Index of Extinct Animals in the Last 100 Years

Now let us have a detailed look at some of the prominent extinctions in last 100 years, and the causes behind these extinctions. May be going through the list will help us in realizing how we were, directly or indirectly, responsible for the tremendous loss our planet has undergone over the years.



Arabian Ostrich

Arabian ostrich, also known as the Middle Eastern ostrich, is a subspecies of ostrich native to the Arabian Peninsula. Arabian ostrich extinction was triggered by the widespread introduction of firearms, which made hunting a relatively easy task. By the beginning of 20th century, Arabian ostrich had become relatively rare, and by mid 20th century the bird had virtually vanished. The last sighting of this subspecies had been recorded in 1966, wherein a dying individual was found near Petra, Jordan.

Atitlan Grebe

The Atitlan Grebe, also known as the Giant Grebe or the Poc, was a water bird endemic to the Lago de Atitlán in Guatemala. A full grown bird reached to the length of about 46-50 cm and resembled the Pied-billed Grebe to a great extent. Introduction of the Smallmouth bass and Largemouth bass species of fish in Lake Atitlan in 1950s and 1960s, reduced the number of crabs and fishes in the lake, thus depleting the source of food for the Atitlan Grebe. The population of these water birds decreased to 200 in 1960, and further to less than 80 by 1965. Though there was a slight recovery in 1970s, an earthquake, that hit Guatemala in 1976, fractured the lake bed and drained the water. This loss of habitat severely affected the Atitlan Grebe population and the bird was last seen in 1989.

Bali Tiger

The Bali tiger, native to a small island in Indonesia named Bali, is the smallest of the three subspecies of tigers found in Indonesia. The deforestation caused due to human encroachment was the major factor which affected the basic existence of the Bali tiger. This was followed by extensive hunting of this species, especially during the World War II, which had a serious impact on the tiger population and by the end of the World War II the animal was virtually extinct. The last documented sighting of a Bali tiger was in form of an adult female that was killed in West Bali in September 1937.

Barbary Lion

The Barbary lion, also known as the Atlas lion, was a subspecies of lion native to Northern regions of Africa. Weighing between 440 to 600 lbs, the Barbary lion was considered to be the heaviest among the lion subspecies. Excessive hunting led to the depletion of Barbary lion population in the wild. Loss of habitat due to the expansion of agricultural lands was also a prominent cause of Barbary lion extinction. Initially declared extinct, the animal was later given the special status - 'extinct in the wild' (EW) by the IUCN as a few individuals were found to be alive in captivity in zoos and circus.

Bubal Hartebeest

The Bubal Hartebeest was a subspecies of antelope that inhabited the African nations of Algeria, Egypt, Libya, Morocco and Tunisia. The animal was caught and domesticated by the Egyptians in order to perform sacrifices. By the beginning of the 20th century, the population of Bubal Hartebeest depleted to a large extent, and its habitat was only restricted to Algeria and Morocco. In Morocco, hunting by French further decreased the number of this species. During the same time many individuals were caught and kept in the zoos, where they eventually died. The last known Bubal Hartebeest was a female that died in a zoo in Paris in 1923 thus bringing an end to this antelope subspecies.

Bushwren

The Bushwren was a small bird, native to New Zealand, which was characterized by nesting on or near the ground. It was found in abundance throughout the country till the introduction of mustelids - predatory mammal from weasel family, was introduced on the Island. The first half of the 20th century was marked by rare sightings of Bushwren. A subspecies of the bird, Stead's Bushwren, found on Stewart Island, got extinct due to excessive predation by the feral cats. As the last attempt to revive the population, they were transferred to Kaimohu Island, where the last sighting took place in 1972.

Canarian Black Oystercatcher

The Canarian Black Oystercatcher, more popular as the Canary Islands Oystercatcher, was a shorebird found on the Canary Islands in Spain. The bird disappeared from its natural habitat in the beginning of the 20th century. It is assumed that the disturbance by the local people and predation by rats were the prominent reasons for the extinction of Canarian Black Oystercatcher. Some theories also suggested that loss of habitat was responsible for the extinction. According to the local fishermen and the lighthouse keepers, the last sighting of this species happened in 1940s. After several attempts to find this bird failed, finally it was declared extinct through IUCN Red List for 1994.

Cape Verde Giant Skink

Cape Verde Giant Skink, also known as the Cocteau's Skink, was a reptile endemic to the Cape Verde islands of the Atlantic Ocean. Loss of habitat, owing to human activities, is supposed to be the main cause of extinction of Cape Verde Giant Skink species. These reptiles were hunted extensively for food and 'skink oil' in the beginning of the 20th century. Some also suggest that prolonged drought that hit the area during this time led to the extermination of these species from the Cape Verde Islands. Attempts to breed these reptiles in captivity were of no avail, and finally Cape Verde Giant Skink was declared extinct in 1914.

Caribbean Monk Seal

The Caribbean monk seal, also known as the West Indian monk seal is a species of seal native to the Caribbean sea and the Gulf of Mexico. The male Caribbean monk seals could grow to a length of 3.5 meters and weigh up to 440 lbs, while the females were a bit smaller. The last recorded sighting of the Caribbean monk seal was at the Serranilla Bank in the western Caribbean Sea in 1952. It is the only species of seal, which was driven to extinction by human activities. More on Caribbean monk seal declared extinct.

.Carolina Parakeet

The Carolina Parakeet was the only species of parrot native to the eastern United States. It inhabited the forests ranging from Ohio Valley to the Gulf of Mexico. There were several reasons for the extinction of this species, most prominent being clearing of forest land for agricultural purpose, which led to loss of habitat for the bird. They were extensively hunted for their colored feathers, which were used for decoration. Large scale culling was executed by farmers, who considered these birds to be pests. Some theories also suggest introduction of honey bees and a mysterious poultry disease played an important role in extinction of these beautiful birds. The last Carolina Parakeet in the wild was killed in Florida in 1904, while the last individual of this species in captivity died in Cincinnati Zoo in 1918.

Caspian Tiger

The Caspian tiger, also referred to as the Persian tiger, is a subspecies of the Siberian tiger native to the vast regions of Western and Central Asia. The extinction of the Caspian tiger can also be attributed to the large scale extermination of this animal by the Russian administration to reclaim land in the beginning of the 20th century. Different accounts suggest a different date, ranging from 1940s to as recent as 1997, as the last sighting of the Caspian tiger, but most of these accounts confirm that the Caspian tiger got extinct in 1950s.

Caucasian Wisent

The Caucasian Wisent was a subspecies of wisent, the European bison, native to the Caucasus mountains in eastern Europe. Until the 17th century, Caucasian wisent was only threatened by predators such as the Asiatic lion, the Caspian tiger, wolves and bears. With the commencement of human settlement in these mountains, the range of Caucasian Wisent decreased considerably. At the same time these species were confronted by a new threat - poaching. Excessive poaching and loss of habitat depleted the wisent population to a great extent, with the number falling to less than 600 by 1917, and further down to less than 50 by 1921. The failure to curb local poaching resulted in the extinction of Caucasian Wisent, with the last reported individual being killed in 1927.

Colombian Grebe

The Colombian grebe was an aquatic bird native to the Bogota wetlands in Colombia. The population of these subspecies of grebe was largely hit by loss of habitat and predation. Wetland drainage, siltation and reed harvest led to destruction of Colombian grebe habitat to a great extent. More importantly, predation by rainbow trouts and hunting by humans curbed the growth of grebe population in this area, with only 300 individuals surviving by 1968. The Colombian grebe population further declined drastically with only a few sightings reported in 1970s, with the last sighting being reported in 1977.

Crescent Nail-tail Wallaby

The Crescent Nail-tail Wallaby was a subspecies of the Nail-tail Wallaby which inhabited the woodlands and scrubs of the west and center of Australia. These birds were found in abundance in Western Australia till the onset of 20th century, but within a decade the wallaby population witnessed a steep slide. Rare sightings continued for some more time till 1920s. The last collected Crescent Nail-tail Wallaby was found trapped in a dingo trap in 1927. The species did survive in wild till 1950s, but the spread of red fox finally triggered Crescent Nail-tail Wallaby extinction.

Golden Toad

The Golden toad, also referred to as the Monteverde toad or the Orange toad, was a true toad endemic to the cloud-covered tropical forests of Costa Rica. The beautiful amphibian disappeared from the Earth's ecosystem in 1989. The extinction of Golden toad is believed to be a part of the large scale decline of amphibian population owing to sudden climate change triggered by global warming. Among the other factors held responsible for the sudden extinction of the toad species, the prominent ones are fungal epidemic which swiped out the amphibian population and unusual warm dry climate, which led to early evaporation of pools even before the tadpoles matured.

Grand Cayman Thrush

The Grand Cayman Thrush was a bird from the Turdidae family, endemic to Grand Cayman i.e. the largest of the three Cayman Islands. Soon after its discovery, this beautiful bird became a favorite among the bird collectors. More importantly, the habitat of Grand Cayman Thrust was largely affected due to excessive deforestation and frequently occurring hurricanes between 1932 and 1944. Loss of habitat made them an easy prey for hunters and bird collectors alike. By the end of the first quarter of 20th century, the bird had virtually become extinct. The last reported sighting of this species was in the north of East End in 1938.

Guam Flying Fox

The Guam Flying Fox was a small megabat or fruit bat, native to Guam the southernmost islands among the Marianas island chain. Considered a delicacy in Marianas, this species of fruit bat was extensively hunted as a food source, which led to its extinction in the mid 20th century. Other than this loss of habitat owing to World War II and predation by brown tree snakes led to extermination of the Guam flying fox from the island. The last Guam flying fox was spotted at Tarague cliff in 1967.

Javan Tiger

Javan tiger was a small subspecies of tiger endemic to Java in Indonesia. The Javan tiger was small compared to most of the tiger species. Excessive hunting and loss of habitat led to the extinction of the Javan tiger in the 1980s. Increase in human settlements on these islands led to habitat destruction for the Javan tiger as well as the Bali tiger. This reduction in habitat eventually resulted in competition with leopards and wild dogs for the available prey species. Excessive hunting also added to the woes of this animal. By 1950s, only around 25 tigers were surviving in the wild. The number went declining and soon resulted in extinction of the Javan tiger with the last confirmed sighting coming way back in 1972.

Western Black Rhinoceros

The Western Black Rhinoceros, also known as the West African Black Rhinoceros was a native to savanna of central-west Africa. This rhinoceros species was severely affected by heavy poaching in the beginning of the 20th century. By 1980s there were only few 100 Western Black rhinoceros left, and the number further declined to an estimated figure of 10 by 2000. Illegal poaching and failure on the part of the administration, either to curb poaching or punish poachers finally resulted in the extinction of Western Black rhino in 2006.

Tasmanian Wolf

The Thylacine, more commonly known as the Tasmanian tiger or the Tasmanian Wolf, was native to continental Australia, Tasmania and New Guinea. Being the last member Thylacinus genus, the extinction of Tasmanian Wolf in 1936 marked the extinction of the genus itself. The most prominent factors which led to the extinction of this animal were extensive hunting, introduction of dogs and human encroachment. Although debatable, yet another factor which supposedly played a vital role was the spread of diseases. The last known sighting of the Tasmanian wolf in the wild was recorded in 1930, when a local farmer killed one specimen in Mawbanna, while the last known specimen in captivity died in 1936.

These were the animals that got extinct in the last 100 years. Today they can be only seen in form of pictures in books and stuffed animals in museums. Other than the above mentioned members of animalia, species like Dutch Alcon, Blue Desert Rat-kangaroo, Syrian Wild Ass and Thick-billed Ground-dove also became extinct in the last 100 years. But relatively less was known about these animals and hence theories about their extinction do exist, but they are not concrete.

The exact cause of the extinction of

may not have been ascertained as yet, but the causes of extinction of almost all the faunae in the above mentioned list of extinct animals in the last 100 years can be traced to human activities, either directly or indirectly. These causes range from loss of habitat caused by human activities to excessive hunting or poaching. The IUCN list of

is also growing longer with time. The rate at which we are loosing these animals is alarming, and if proper measures are not taken soon we may end up loosing a large chunk of animal kingdom. This will indirectly affect us, in fact the adverse effects have already started to show. Tigers will be left with no option, but to encroach human settlements for food if the deer population is exhausted. On the other hand if tiger population is exhausted, the number of herbivores will rise which in turn will lead to depletion of vegetation cover due to overfeeding by these herbivores. In short, extinction of a particular species puts tremendous pressure on the other species as well as the ecosystem. And its high time we understand that we are a part of the ecosystem and any alterations in the ecosystem are invariably going to effect us.