The only alternative I can think of is back when they attributed a different mechanism to the same phenomena
Like instead of random mutations that get selectively filtered for the benefit of the species, it was "the giraffes stretch their necks to reach high leaves and somehow this makes their babies have longer necks"
Still evolution.
I'm in a class which studied history of evolution for 6 weeks, so I know quite a bit about those theories, actually. In fact Darwin had no specific mechanism of heredity. That was one of the things his theory was criticized on. Actually, the random mutation theory was originally considered an alternative to Natural Selection. It gained more ground and became the more accepted theory when Mendel's work was discovered. They didn't merge until the modern synthesis around the mid-early 20th century.
And the soft theory of heredity you mentioned came quite a bit before Darwinism was thought up by Lamarck. It was known as Lamarckism. It was never considered seriously in science, it was a theory held by radicals. It opposed Darwinism until it was eventually discredited as a theory. It was easy enough to show that if you chopped off mouses' tails over generations, their babies would still grow tails.
Damn, semi-ninjad by MSH.
best theory ever that I just made up:
The big bang happened, and everything was fine all the way up through the creation of the Earth. But instead of life starting out as single-celled simple things, inorganic molecules randomly came together in such a way to perfectly create all of the multicellular complex organisms we see today.
It... it's basically creationism but attributing it to EPIC RANDOMNESS rather than some kind of intelligence.
So basically it's EXTREMELY INSANE
I kind of hope in a morbid, pessimistic sort of way that someone somewhere actually believes this.
But we have the likes of the FLAT EARTH SOCIETY so I guess it's not that much of a stretch.
Too late, already taken. That was the original view of the Greek atomists. Except it wasn't organisms being randomly made from inorganic molecules, it was everything being made of the random acts of atoms.
You lose by over 2000 years, AND they had a more extreme view.