Approximately 130,000 years ago.
God pronounces all of his creation "good" at the end of each day, yet we are told (by evolutionists) that millions of years of death, decay, and suffering have occurred previously.
Since animals don't have immortal souls, aren't rational, and aren't made in the image of God, there is no evil in animal death or suffering. That's why it is not a sin to eat meat.
By the way, you have to reject a lot more science than just evolution if you want to believe there was no animal death before sin. You're arguing against geology as well as the fosil record.
The Bible says that Adam was created to live forever until he sinned, and he was then cursed with death.
When evolution reached the point at which the mind of a pre-human homonid was sufficiently advanced, God infused an immortal soul into him, and thus Adam was created. God granted him the gift of immortality, which he squandered by sinning. Because of him, the gift of immortality was revoked from all his descendents.
Notice that none of the above can be scientifically falisifed. Of course, that means it can't be scientifically verified, so it's not a scientific belief. But that's okay, because there is more to life than science.