What aspect of terrestrial biosignatures introduces context, making the finding of microbial life in an Antarctic ice core more surprising than in a known hydrothermal vent?

Answer

Environmental bias

Environmental bias refers to the location context; finding life thriving in a niche deemed too hostile or transient (like ancient ice) is more surprising than finding it in an environment already known to support it (like a hydrothermal vent).

What aspect of terrestrial biosignatures introduces context, making the finding of microbial life in an Antarctic ice core more surprising than in a known hydrothermal vent?
sciencelifedetectionbiosignature