Changes

On their foreheads resides a small unnamed diamond-shaped organ with a rigid carapace that contains ultra-dense hormonal fluids which emits an overpowering scent. The rear ganglia of their brains connects to their central lobe, and their head also contains polyp-structures vaguely reminiscent of pheromone glands amongst [[Terra]]n invertebrates, specifically [[Wikipedia:Bombyx mori| Silk Worms]]. Comparative Imperial studies of members of other Tau castes show the ethereals have a comparatively smaller olfactory cavities. [[Magos Biologis]] [[Sharle Darvus]], having dissected a Tau Ethereal, speculates this organ to play a role in controlling other castes via a pheromonal communication system or chemical 'signifiers.'{{Fn|1b1c}} [[Inquisitor]] [[Brehm Sasham]] was firmly of the opinion that this form of "chemical puppetry" could prove a weakness in the Ethereals' control over the T'au{{Fn|1b}}