"New? Not at all. I myself am at least six to seven hundred years old."
It was just a guesstimate as it was difficult to tell the time that passed in Hueco Mundo, and because he had started as a human soul and then gone from hollow to arrancar, personality shifting with every evolution and memories fading. There was a reason why hollows and arrancar were creatures of desire, and that was because they had lost their humanity and longed for some feeling of completion.
"Hollows, and Arrancar, have been around for as long as humans, I'd think. Unless human souls were originally different."