A new study shows that humans have decimated 469 bird species in the Earth’s last 50,000-year-old history.

Scientists at Tel Aviv University and the Weizmann Institute found avian endured a major extinction event starting 20,000 years ago that ended with up to 20 percent of species disappearing – but researchers say the real number is much higher.

The extinct species of most animals were large and lived on islands. They were also flightless.

This includes the massive Moa that lived in New Zealand and went extinct in the 17th century and the infamous dodo bird, which were native to island of Mauritius off the coast of Madagascar – it went extinct in the 1600s.

According to researchers, the extinctions were caused by humans arriving on islands to hunt large birds for food.

Shai Meiri, of The George S. Wise Faculty of Life Sciences, and the Steinhardt Museum of Natural History, Tel Aviv University, stated in a statement that they had conducted a thorough review of scientific literature and collected quantitative data about the number and traits of birds around the world.

Also Read: Coyote Attacks Woman Jogging in Park

“Those species that have become extinct within the past 300 years are well-known, but earlier species are more easily discovered from fossils found at archaeological and paleontological sites around the world.

“We were able to identify 469 species that have disappeared in the past 50,000 years. However, we believe the true number is higher.”