Could it be that their explanations have changed because their conclusions have been found to be incorrect?
Just asking....
If your teachers and textbooks taught you that the theory of evolution addresses the origins of life as such, then you had inferior teachers and textbooks, I am sorry to say.
Could it be that their explanations have changed because their conclusions have been found to be incorrect?
In that case one would expect Darwin to address the question of life's origin in his 1859 classic The Origins of Species, no? Yet in my copy not one of the fourteen chapters deals with that.