The Brainy Jellyfish
Jellyfish and their cousins are often described as the simplest animals without nervous systems. Because evolutionary scientists have thought jellyfish were such simple creatures, and because many of them show up early in the fossil record, jellyfish were said to be among the earliest animals to evolve.
Marine biologists have been surprised to learn that the modern populations of jellyfish and their cousins are actually much more complex than they ever suspected. Creationists point out that because there are so many of these creatures, there was also probably a large population in the past. The more common a creature is, the more likely it is to be found in the deeper rocks of the fossil record.
More recently, scientists have learned that the supposedly simple nervous system of the jellyfish is actually not so simple. They have confirmed that at least one type of jellyfish has a nervous system with the same advanced features found only in mammals and humans. Most animals generate electrical impulses using sodium. However, like humans, this jellyfish can generate different kinds of impulses depending on whether sodium or calcium is used. Thus, the jellyfish can send twice as much information through its nervous system as most other animals!
We're learning that when humans refer to a creature as simple, it's probably because of human ignorance of the creature, not because it's a simple form of life. This should remind those of us who believe in creation that all things witness in support of God's wisdom, not human stories of evolution.