Island gigantism - Artensterben

Historical depiction of Aepyornis maximus. Our knowledge of the elephant birds’ external appearance is incomplete: there are no preserved specimens, only bone finds and eggshells. Reconstructions therefore rely on anatomical inferences and comparisons with modern ratites. (© http://www.50birds.com/gextinct5.htm, Public domain, via Wikimedia Commons)

3. February 2026 Doreen Fräßdorf

Aepyornis maximus – the largest elephant bird and the mystery of when it went extinct

There wasn’t just one elephant bird The elephant bird is probably one of the best-known of all extinct birds. Hardly any other animal so strongly embodies gigantism, enigmatic traditions, and the fascination of a world of animals that humans now know only in fragments. But the name already misleads: there

A Haast's eagle attacks already extinct New Zealand moas. The largest moas were the female South Island giant moas. They could reach a weight of up to 300 kilograms. (© John Megahan, CC BY 2.5, via Wikimedia Commons)

15. September 2024 Doreen Fräßdorf

Haast’s Eagle

The largest bird of prey in modern times Before humans settled New Zealand about 700 years ago and introduced invasive species like cats and rats, there were no land-dwelling mammals on the islands – aside from three species of bats. Instead, the ecosystem was dominated by approximately 250 bird species.

New Zealand’s unique bird life evolved in isolation over millions of years. The image, created at the end of the 19th century, shows a hunting scene of moas. (© Joseph Smit, Public domain, via Wikimedia Commons)

27. July 2024 Doreen Fräßdorf

In the Footsteps of Moas: Where New Zealand’s Flightless Birds Find Refuge

The settlement of the Pacific Islands by humans led to rapid waves of extinction for many animal species, whose dynamics are difficult to reconstruct. Among the affected species were the wingless moas, which were only found in New Zealand. These often massive birds went extinct in the 14th or 15th

Replica of Delcourt's giant gecko or Kawekaweau gecko from the Lille Natural History Museum in France. (© Musée d'Histoire Naturelle de Lille, CC BY-SA 4.0, via Wikimedia Commons)

26. May 2024 Doreen Fräßdorf

Delcourt’s Giant Gecko

The largest gecko in the world … In the early 1980s, French museum employee Alain Delcourt discovered a forgotten specimen of a single stuffed giant gecko in the basement of the Natural History Museum of Marseille, which had previously been on public display for years. This species was previously unknown

Illustration of the Cape Verde giant skink by J. Terrier from 1885. Males could reach a body length of around 50 centimeters, females just under 43 centimeters (including tail). The animals weighed almost half a kilo. (© J. Terrier, Public domain, via Wikimedia Commons)

21. June 2021 Doreen Fräßdorf

Cape Verde Giant Skink

Ilhas Desertas—the terra typica of the Cape Verde giant skink Organisms that occur in isolated ecosystems such as islands are often adapted to the extreme conditions prevailing there. They exhibit characteristics such as dwarfism or gigantism and often lack defensive mechanisms due to the absence of predators, setting them apart

The extinct Antiguan curly-tailed lizard, like the still-living Northern curly-tailed lizard Leiocephalus carinatus (pictured), belongs to the genus of curly-tailed lizards. (© Ianaré Sévi, CC BY-SA 3.0, via Wikimedia Commons)

27. September 2018 Doreen Fräßdorf

Antiguan curly-tailed lizard

A reptile of disgusting appearance A Mrs. Lanaghan (also Lanagan) provided in 1844 in Antigua and the Antiguans a description of a reptile that could be the Antiguan curly-tailed lizard. She described a ground-dwelling lizard that was “considerably larger” than those in trees. Along its body ran “longitudinal blood-red stripes”

Bones of the North Island giant moa at the Auckland War Memorial Museum. (© Auckland Museum, CC BY 4.0, via Wikimedia Commons)

26. February 2018 Doreen Fräßdorf

North Island giant moa

The second-largest moa species This moa species inhabited scrub, grassland and dune landscapes as well as forests on New Zealand’s North Island. The North Island giant moa is considered the second-largest moa species. The largest species is the South Island giant moa, which was endemic to New Zealand’s South Island.