Giant Sandworms?

Is it even possible for a sandworm the size of those shown on Dune's fictitious "Arrakais"? Why not? What are invertebrates? How could a giant sandworm exist? Dr. Anna Allen, with the U.S. National Science Foundation explains all things invertebrate.

[@NSFScience]

ua-cam.com/video/sT8SVDkfaoc/v-deo.html

[@tylerhloewen]

hmmm, this video only asked questions, and provided no information or links to get the answers. I'm not even sure what program it is promoting. Edit: they now have the link

[@jfabiani]

"Join me to learn how worms impact..."
Okay. How?