It was understood, Humans ate the Dodo.
New timeline: Human brought other animals that ate them all
For thousands of years, on the island of Mauritius, without natural predators, the flightless Dodo has it good. 100 years after Humans settled there too though, the Dodo was no more, approx. 1681.
The old story was that Humans ate them. But they taste awful. With Humans came pigs, rats, & monkeys which ate or competed for food with the Dodo.
Note: the Dodo might not even BE extinct!