A biological fall from grace?

Ok, the more daring of you, long long ago living cells split into several lifestyle variants (many do more than one), but the primary ones split those that make their own food (from whatever source of energy) and those that take theirs from others, often but not always including the death of the other, which can either be a simple fact (scavenging) or murder (predation).

It just seems to me that if one were looking for a biologically salient 'fall from grace' this would be it.

Jess Tauber

Scavenging is just recycling biowaste so I wouldn't consider that a fall from grace. Predation is also recycling but it involves a victim - though it helps the 'victim' species improve itself by introducing a survivorship bias toward stronger traits.