Subject: Cetacean Tear Ducts?

Aldemaro Romero (
Tue, 10 Mar 1998 23:42:57 -0500

> Date: Tue, 10 Mar 1998 21:15:32 -0500
> From: Brian Burt <>
> To: aRomero@ACC.FAU.EDU,
> Subject: Cetacean Tear Ducts?
> Dear Dr. Romero -
> This is probably a strange question, but I was wondering if cetaceans
> have functioning tear ducts.  My first thought was that they would seem
> unnecessary for a marine mammal (at least for moistening tissue,
> flushing out foreign substances, etc.), but then it occurred to me that
> this might be a holdover characteristic from the evolutionary past.  If
> tear ducts are present, what functions do they serve for cetaceans?
> Thank you for your assistance!
> - Brian Burt

Dear Brian:

Actually, this is an excellent question. There are no tear ducts among
cetaceans, yet they have a gland that secretes an oily substance that
lubricates and cleans the eyes.  It has been argued that this substance
serves to streamline fast moving cetaceans (like dolphins) as they swimm
and that they contain some sort of antibiotic properties.

Best wishes,

Aldemaro Romero, Ph.D.