The labyrinths are first developed, ossific granules making their appearance in the region of the lamina papyracea between the fourth and fifth months of fetal life, and extending into the conchæ.
Some birds and other migratory animals have deposits of biological magnetite in their ethmoid bones which allow them to sense the direction of the Earth's magnetic field.
These openings let opportunistic bacteria in the nasal cavity enter the sterile environment of the central nervous system (CNS).
This injury is not fatal, but can be dangerous, as when a person fails to smell smoke, gas, or spoiled food.
[3] In fact, people with anosmia were more than four times as likely to die in five years compared to those with a healthy sense of smell.
[8] This article incorporates text in the public domain from page 153 of the 20th edition of Gray's Anatomy (1918)