Five of my original nine tadpoles have morphed. One of the four remaining tads died last week. He had developed his back legs seemed to be doing well then one morning when I went to feed them he was dead.Two others have back legs and you can see they are growing but the last one seems almost unchanged from when we first collected them. A couple of weeks ago I noticed the bigger tads picking on the small one so I separated him from the others. Could this tad have some kind of defect that prevents it from maturing? Could it possibly be a different kind of tadpole? It has always been smaller and paler in color than the others which are Gray Tree Frogs.