Earlier in the Holocene, Madagascar had a number of megafaunal mammals: giant lemurs such as "Archaeoindris" which at over 200 kg was comparable in mass to the largest gorillas, as well as the hippopotamuses. The island also hosted flightless elephant birds weighing up to 700 kg, the largest known birds of all time. All of these went extinct following the first appearance of humans about 2000 years ago. Today, the largest surviving native mammals of the island, such as the indri and fossa, have weights only approaching 10 kg. Most if not all of the 29 listed extinct species are believed to have died out in prehistoric times; none of these are known to have survived into the post-European contact period.