The Tholians are a xenophobic but not unreasonable people. While they prefer to limit contact with outsiders and unrelentingly guard their territory, the Federation currently enjoys friendly, if distant and limited, diplomatic relations with the Tholian Assembly. The most notable aspect of the Tholians is their unique anatomy. Far from humanoid, the Tholians evolved on an intensely hot planet with a high-pressure atmosphere. In fact, the Tholians would quickly perish in any environment suitable for humanoid habitation. The Tholians seem to be encased in a mineral-based carapace that gives them the appearance of living crystals, which combined with their six spindly legs and glowing eyes can give the Tholians a frightening aspect to those unfamiliar with them. The Tholians are intelligent, impatient and short-tempered - they do not suffer fools or trespassers lightly. Despite their naturally aggressive nature the Tholians rarely venture past their own systems. As such, when dealing with the Tholians a 'live and let live' approach is generally advised - the Tholians are unlikely to bother those who do not bother them. It is extremely ill-advised to enter their space without their express permission.