Premise:
"The Victorious Immune Evolutionary biologists speculate that a hypersensitive immune system was needed back when parasites were ubiquitous and deadly."
Hypothesis: The Victorious Immune Evolutionary biologists theorize what kind of immune system was needed in the past.

yes

Premise:
"If this process continued, it might lead to a situation where all of the collection, sorting, and transporting of the mail is privatized."
Hypothesis: The process could potentially lead to the privatization of mail transportation.

yes

Premise:
"However, a change would not seem likely to have a negative impact, since, in contrast to the current policy, it would be consistent with the airlines' position that frequent flyer miles belong to the individual traveler."
Hypothesis: Individuals are groups of people or businesses that work as a team to achieve a goal.
no