The answers to the pictures shown are
1. (unbalanced) translocation
2. deletion
3. inversion
4. duplication
ANSWER:
Its because mother nature tells us herself!
its just like predicting when rhinos will go instinct:
imagine people killing 2 rhinos a week or every two weeks and theres only 500-1000, you can predict that in prob 3-5 years they'll go instinct
so its just like that and they have much higher technology now that it'll just give them the answer without putting much effort into it.
~batmans wife dun dun dun....
Without using the scientific method, it would be much harder to determine a factor that could cause your experiment to fail. By sticking to only one of the methods you could easily destroy your experiment without the background search needed or the materials planned out.