The Rev Dodgson said:

Iodine is an essential dietary mineral that the thyroid gland uses to make key hormones that regulate metabolism, growth, digestion, heart rate and body temperature.

For quite a long time, I considered this to be evidence against the existence of God (or intelligent designer). To require the use of a rather rare element (60th most abundant element in the Earth’s crust) in a message molecule seems like a design flaw to me.