when did elephant birds go extinct

This study was funded in part by the Australian Research Council and other international funding bodies.

Madagascar’s extinct elephant birds – the largest birds ever to have lived – have captured public interest for hundreds of years. Little is known about them due to large gaps in the skeletal fossil record.

A new study published today in Nature Communications used ancient molecules extracted from fossil eggshells to reveal surprising new insights into the biology of these flightless giants. How many species were there? Where did they live? What did they eat?

Answers to these questions contribute to our understanding of the origin and loss of species, which is especially important today as global biodiversity continues to rapidly decline.

As a biodiversity hotspot, the island nation of Madagascar is a natural test tube for studying evolution and extinction. The numerous species of now-extinct megafauna that once roamed there play a key role in furthering our understanding of these processes.

One such group were the elephant birds, about which precious little has been gleaned since they were first described over 150 years ago.

Alongside Africa’s ostrich, Australia’s emu and cassowary, South America’s rhea, and New Zealand’s moa and kiwi, the elephant birds of Madagascar (or vorompatra in Malagasy language) were large, flightless ratites. They became extinct around 1,000 years ago, soon after humans first settled Madagascar.

These were truly enormous birds, with some weighing over 700kg and standing up to 3m tall. Their eggs, weighing 10kg, were 150 times the size of a chicken’s egg.

Elephant birds (Aepyornithiformes) have been the stuff of legends for hundreds of years, with early sightings possibly being the origin of the mythical creature, roc (or rukh), and inspiring writers such as H. G. Wells. British naturalist David Attenborough also took a special interest in elephant birds, documenting his journey for answers about his own elephant bird egg in Attenborough and the Giant Egg.

In recent years, elephant birds were found to be most closely related to the chicken-sized kiwi bird – a result that changed our view of avian evolution.

Yet there is still debate about how many species of elephant bird there actually were. At one time, 16 species were named based on differences found between skeletal fossils. In the 1960s, this dropped to seven species, and the most recent revision classified elephant birds into four species. But why the controversy?

Although these birds became extinct relatively recently, the skeletal fossil record through time and space is patchy. Madagascar’s climate can be very hot and humid, which is not conducive to preserving biological material.

When bones are incomplete or fragmented, it can be hard to tell apart different species – and sometimes, bone doesn’t preserve at all, like in the far north of Madagascar where there have been reports of eggshells but no bones.

Modern DNA technology can help overcome this barrier. In a similar way that we can identify people, or tell how they are related to each other by comparing their DNA, ancient DNA from fossils can help identify unknown specimens or uncover relationships within and between species.

The more differences there are between two organisms’ DNA, the more distantly they are related. These differences can then be used estimate when species evolved, which provides clues about how and why. But, just like the elephant bird bones themselves, the DNA within them is not well preserved either.

Biology edit

Examination of brain endocasts has shown that both A. maximus and A. Hildebrandti shared a nocturnal lifestyle with their closest surviving relatives, the kiwis, and had significantly smaller optic lobes. A lesser extent of reduction was also seen in the optic lobes of Mullerornis, which may indicate a nocturnal or crepuscular lifestyle. A. maximus had relatively larger olfactory bulbs than A. hildebrandti, implying that the latter lived in open environments while the former inhabited woodland settings where the sense of smell is more advantageous. [22].

Species edit

The genus Aepyornis contains up to 10 or 11 species that have been described[13], however many of these have been contested as valid, with some authors classifying them as a single species. maximus. Up to three species have been described in Mullerornis. [14] According to recent research, there are only three species of elephant birds—two in Aepyornis and one in Mullerornis. [15].

  • [Aepyornithes Newton 1884][13]Genus Aepyornis Geoffroy Saint-Hilaire 1850[16] (Synonym: Vorombe Hansford) Order Aepyornithiformes Newton 1884

While most authors place all elephant birds in the single family Aepyornithidae, others argue that Aepyornis and Mullerornis belong in different families within the Aepyornithiformes, with the latter in the Mullerornithidae family. [15].

Discovery edit

Elephant birds have disappeared since the 17th century at the latest. Étienne de Flacourt, a French governor of Madagascar in the 1640s and 1650s, spoke of an ostrich-like bird that was rumored to live in remote areas, but it’s unclear if he was retelling old stories from previous generations. In 1659, Flacourt described the “vouropatra, a large bird that haunts the Ampatres and lays eggs like ostriches; it seeks the most lonely places so that the people of these places may not take it.” The idea that the fabled roc from Marco Polo’s tales was ultimately based on elephant birds has been conjectured, particularly in the latter part of the 19th century, but this is contested. [4].

In Madagascar, between 1830 and 1840, European explorers observed enormous eggs and eggshells. [3] Because they were aware of the moa in New Zealand, British observers were more likely to accept the reports of enormous birds and eggs. [3] In 1851 the genus Aepyornis and species A. based on bones and eggs recently recovered from the island, were scientifically described in a paper submitted to the Paris Academy of Sciences by Isidore Geoffroy Saint-Hilaire. This led to extensive coverage in the popular presses of the era, especially because of the eggs’ enormous size. [4].

The Scott River egg from the 1930s and the Cervantes egg from 1992 are two complete eggs discovered in dune deposits in southern Western Australia; these have been identified as Aepyornis maximus rather than Genyornis newtoni, an extinct giant bird known from Australia’s Pleistocene period. According to one theory, the eggs traveled across the Antarctic Circumpolar Current from Madagascar to Australia. The discovery of two fresh penguin eggs that washed up on Western Australia but were originally from the Kerguelen Islands, as well as the discovery of an ostrich egg floating in the Timor Sea in the early 1990s, provide evidence in favor of this theory. [5].

FAQ

How did elephant birds become extinct?

It has been understood that the arrival of humans on Madagascar drove megafauna like elephant birds, giant lemurs, and the Malagasy hippopotamus to extinction over a few centuries, both through hunting and also competition for habitat, as when humans started clearing forests to create agricultural fields.

When was the elephant bird last seen?

A 2021 study suggested that elephant birds, along with the Malagasy hippopotamus species, became extinct in the interval 800-1050 AD (1150–900 years Before Present), based on the timing of the latest radiocarbon dates.

How many elephant birds are left?

Elephant birds are an extinct family of flightless birds. They were believed to have existed on the islands of Madagascar during the Pleistocene and Holocene. They went extinct around 1000–1200 CE. The New Zealand Kiwi is their closest modern relative that is still in existence.

How tall did elephant birds get?

Some forms of Aepyornis attained very large size, approaching 3 metres (10 feet) high and weighing about 450 kg (1,000 pounds).