Pig-out thanks to a second aorta

27februari2008
Source: trouw.nl
Crocodiles are well known for their voraciousness. The animals are capable of having enormous meals in very short amounts of time, after which they do not need to dine for a long time.
Biologists of the University of Utah started a research on the eating habits of crocs. By feeding young crocs, they discovered that these animals were capable of consuming 23 % of their own bodyweight in food in one meal. The biologists expect that this percentage may be even higher in adults. To compare these eating habits with humans: it would correspond to a human weighing 70 kilos eating a steak of 17 kilos! A human cannot handle such amount of food, but a croc can. After such a meal, it doesn’t need to eat for months.

The biologists have discovered that crocodiles are capable of doing this thanks to an extra blood vessel, the left aorta. After a crocodile has eaten a huge meal, it can divert its blood flow to the stomach and bypass its lungs. This extra blood causes more gastric acid, thus speeding up the digestion. This is important as crocodiles have little energy left to move during the digestion. They will lie in the sun for hours at a time, making the younger animals vulnerable. When the digestion would take too long, chances are also that the food would rot, which would be bad for the crocodile’s health.

The second aorta has been discovered not only in crocs, but also in other reptiles. However, in these animals, a clear link with their digestion has not yet been found.