Many things are fascinating on board the ship. The thing that most fascinated Spock were the Millbrook siblings. They were fascinating to Spock and he wish to learn more about them and their plant.
Unfortunately like Vulcan, there history and culture were very brief in the public. What he found out were the plant Bryn-Hydiy were they used warrior race in battle with each other two different tribes the Bryn and the Hydiy. There was no difference in them same culture with there symbols and powers. Then they suddenly stop fighting. No reason was written in the database. Spock also loved there battle armour with covered them head to toe, for two reasons one to make use that the didn't get hit and two so there powers were hidden which gave them an advantage in battle.
There powers also fascinated Spock as he was Vulcan and had touch telepathy, but all of the Hyryn people had different powers as due to regulation there were required to list all of there powers. Though the streaks in there hair
Red = telekinesis
Blue = body density
Green = touch telepathy
Orange = read peoples faces
Purple = read minds
Pink = breathe under water
Sliver = technopathy
Gold = healing powers
Bronze = control fire
Black = speak with the dead (only 1 in 10,000)
White = can see the future ( only has happened once in know history)
Spock found it fascinating, he thought that the person born with white streaks was the only to unite the two tribes. He wish to learn more, the symbols were not listen under there powers so he thought the symbols burned/tattooed in the skin were like the placebo effect as the thought that the symbols will help them in battle when there were just tattoos.
Although the tought in illogical, the plant was a hot spot for tourists due to them being able to speak to their dead relatives. He wish to know more but didn't know how to ask without prying. He told two under his command.