Pretoria - Bet you didn’t know an ostrich cannot taste or choke on its food? This sounds like a fun fact on a bubblegum wrapper, but it was the research topic of Dr Martina Crole’s doctorate at the University of Pretoria.
Crole, a senior lecturer in the department of anatomy and physiology in the faculty of veterinary science, made these interesting findings during her studies of the upper digestive tract of the world’s largest bird.
Crole received her doctorate on Friday. She had wanted to find out why, although it did not have an epiglottis, an ostrich did not choke. Normally, animals prevent choking by covering the windpipe with the epiglottis.
Ostriches have a wide windpipe (or glottis) that has to be closed during swallowing to prevent choking.
Crole determined that when an ostrich’s windpipe was closed and its tongue moved backwards, the root of the tongue became folded. A pocket in the base of the tongue body encased the front part of the laryngeal mound.
In this position the lingual papillae also hooked over the most rostral laryngeal projections, thereby closing the windpipe along with the folded tongue. This unique mechanism, which essentially replaces an epiglottis, is called the linguo-laryngeal apparatus.
In 200 years, only a few other researchers have noticed the pocket in the tongue and no one, until now, has been able to understand why it is there. “They possibly didn’t realise its function because they did not use fresh specimens, but rather opted for material used in formalin or alcohol.”
Discovering that ostriches don’t have taste buds, Crole said: “I simply couldn’t find any taste buds which might explain why ostriches aren’t fussy eaters.”
It will however only be 100 percent certain that ostriches cannot taste if genetic tests are done. Despite no taste buds, ostriches inspect objects with their sensitive bills and have well-developed smell, touch and sight to discern what can be eaten
. - Pretoria News