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On September 17th, 1998 the Ithaca Journal ran its first "Ask A Scientist!" article in which Professor Neil Ashcroft , who was then the director of CCMR, answered the question "What is Jupiter made of?" Since then, we have received over 1,000 questions from students and adults from all over the world. Select questions are answered weekly and published in the Ithaca Journal and on our web site. "Ask A Scientist!" reaches more than 21,000 Central New York residents through the Ithaca Journal and countless others around the world throught the "Ask a Scientist!" web site.

Across disciplines and across the state, from Nobel Prize winning scientist David Lee to notable science education advocate Bill Nye, researchers and scientists have been called on to respond to these questions. For more than seven years, kids - and a few adults - have been submitting their queries to find out the answer to life's everyday questions.

Previous Week's Question Published: 6 May, 2004 Next Week's Question
Unique jaw lets snake take a big bite
Question
Why can't we swallow our food whole like snakes?

Question
Snakes eat big meals and they don't eat very often - a rattlesnake can eat a rat or a rabbit that weighs up to about one-and-a-half times its own weight, roughly the equivalent of me swallowing and digesting a 260-pound hamburger! Because the snake only needs to eat about three or four times its own weight every year, even if each meal is only about half its weight, five to ten meals a year are probably enough. And snakes don't "unhinge" their jaws to do that!

The way this amazing feat works is easy to see when you watch a pet snake eat a mouse or see a snake feeding on TV. First, the skin stretches much more than ours does, and you can observe a bulge as a big meal moves from a snake's throat down to its stomach. Second, our lower jaws are fixed together at the front, and you can feel where the two halves meet as a groove at the front of your chin (try it!). In snakes the two halves are not attached in front, so they can move separately, and their tips are visible as it swallows a meal. Finally, our jaws attach to our skulls (you can feel the joint move by pressing a finger right below an ear and opening your mouth), but in snakes there is an extra bone BETWEEN the jaw on each side and the skull, so that the mouth can open wider.

Rather than pulling or pushing food INTO its mouth like we do, a snake eats by walking its jaws OVER a meal in a side to side fashion. You can make a simple model to illustrate the difference by clasping your hands, holding your elbows against your sides, and moving your forearms up and down. This is like opening and closing our jaws, and the biggest thing we can eat has to go through the triangle formed by our body and our forearms. Now unclasp your hands (jaws not connected in front), unfold your arms at the elbows (your upper arm is now like that extra bone between a snake's skull and its jaws), and you can move your forearms back and forth around a much bigger hole - just like a snake moves its jaws from side to side to pull its head over a big rat!