One way scientists learn about animals is by studying their poop -- also called "scat" or "dung." Let's look at some animal poop and see if you can guess who left it behind.
"Smithsonian historians, scientists, researchers and other experts share their questions, their methods, and their unique way of thinking in an interactive format that welcomes you to contribute your own ideas during this two-part conference. April 13-14 and April 28-29, 2010."
The Image Gallery is provided as a complimentary
source of high quality digital photographs available from the Agricultural
Research Service Information Staff.
Oldie but a decent one from the government for images and pictures. Remember that with most government sites you are free to use the pictures but some such as NASA do require that you cite the source.