
Background:
One of the more disgusting things that scientists of the world get to do it diet studies. This may not sound bad in principle but how do you truly figure out what and how much of what an animal has eaten. This is a particularly tricky task for marine animals since it is very difficult to observe them for any significant amount of time.
The best way of finding out what an animal has eaten is look at what is inside that animal. Yep, that's right. You have to catch the animal, kill it, and then dissect its innards to find out what kind of animals are in its digestive track. To the untrained eye most things just look like a pile of goo since they are inevitably in some sort of decomposed state but believe it or not people become very good at identifying those piles of goo.
The fact that there are indigestible parts of animals is a huge help to scientists that perform these studies. Body part such as bones, otoliths, beaks and eye lenses can all be counted and potentially linked to a specific prey.
Question:
And so we finally arrive at the questions, how do you tell the difference between fish eye lenses and squid eye lens?
ANSWER:
Keith is correct. Squid and fish eye lenses are different shapes. Fish eyes are sphere shape and squid eyes have a flat surface. Keith you are ready to dig into some guts and start describing food chains.