If you're asking about the length of the line, yes, everybody does flock there first thing in the morning. Still, if you're there when the park first opens and go with the crowd you might walk right on or just wait a short while. Then again, the lines also are pretty short towards the end of the day too.
If you were asking because you've heard that the animals are more active in the morning or in the evening rather than noon, I'm not sure that applies anymore. By the time the park opens the sun's been out for a few hours and it will be around for a few more hours after it closes.
So my suggestion is that if you're there when the park opens to go the other way. Hit Dinoland and Asia which will be empty and then just grab a FastPass for the Safari when you get to Africa. Depending on your return time you should have time to take the train to Rafiki's Planet Watch or possibly catch a Festival of the Lion King Show.