They had been hunting mammoths. They had followed them from Asia to North America.
Memory Loss.
This is because it said "Maria still does extremely well in school. However, she has a hard time remembering everyday activities and things that happened to her in the past." So, it says she has a hard time remembering. This usually happens from Memory Loss.
I hope this helps! :)
Answer:
The features that might make one mystery more fascinating that another are: Predictability; Resolution; Clues available; Surprise; Novelty and Details.
Explanation:
What makes a mystery fascinating is the inability to explain some facts and events in rational way or how they challenge the explanations we have of how the world works with a scientific explanation or logic reasoning.
But the features that makes one mystery more fascinating then another includes how predictable is the story; if there was a resolution; which clues and details were known about the mystery; the level of surprise and novelty in the case. With all this features one mystery still might be very difficult for human understanding making it really fascinating.