If this question refers to evidence from an historical point of view, such as studying dinosaur bones, the answer is palaeontologist.
If the question refers to the collection of evidence from a scientific/medical or even criminal point of view, the answer is forensic anthropologist.
There does not appear to be a name for it.
Weird
Phonographer.
Quodophile.
Someone who collects everything would be called a hoarder - this type of person may have OCD as well.
Some of the names given for a person who collects trains:model train collectormodel train enthusiasttrain modeler
That's an entomologist.
Gun-collector
usher
The person who studing about the shell is calles as chonchologist.
Arachnid collector or Arachnophile.
A Pottea.