While doing MRI scans of the swordfish, the researchers discovered a large gland at the base of the fish's long, pointed upper bill. Coming from the gland was a network of capillaries that connect it to the animal's skin. The gland sends an oily substance to the skin through tiny pores, so the skin is coated with the oil. A close study of the skin of the swordfish revealed microscopic projections. When the oil coats these projections, it produces a water-repellent surface that reduces drag to nearly zero. The swordfish essentially lubricates itself as it rockets through the sea.
A swordfish on the deck of a boat
When you see a design feature that is this specialized, you are faced with a question of how such a feature developed. Trying to explain all of this by chance requires assumptions that are not consistent with life in the sea or with common sense. It would be a major challenge to conceive a way the gland would develop. It does not appear to come from some universal component all fish have. The specialized skin structure is also an issue. Something built for speed is not useful in other settings, and may even be a liability. God designs living things so they can survive in the specialized environmental niche they will occupy. The swordfish is one more example of how we can know there is a God through the things he has made (Romans 1:18 – 23). Source: National Wildlife, December/January 2017, page 8.