Some people ask how a good G-d could allow suffering in this world, why there are disease and illness. Sooner or later an answer comes up that might actually make some sense of the mess.
It has been recently discovered that the Hawaiian bobtail squid, which glows from its belly, actually does so thru the use of bacteria. The chemical produced by the bacteria, tracheal cytotoxin, kills off certain cells in the squid which creates a chamber which becomes a permanent home for the bacteria. This chamber is lit from the bacteria which allows the squid to hide from its predators.
How does this fit into the suffering thing? Simply that G-d created all the variety He did so that all His creation could fulfill a purpose. The very bacteria and chemicals that enable this squid to survive is the very same chemical that causes Whooping Cough and Gonorrhea in us humans. Truly all things are for a purpose whether we see it or not.
**Update**
I forgot to put in the link to the article.