The male erection and ejaculatory reflex require multiple physiological processes to work together in an incredible coordinated manner.
It would be surprising, under an evolutionary view, to find such a complex system in the earliest animal fossils.
To see why, we must remember that muscles first appear in the Cambrian explosion.
Many who have studied the foot recognized its “excellent design.” Leonardo da Vinci called the human foot “a masterpiece of engineering and a work of art.”
Three main things must occur for the young salmon, called a smolt, to prepare for life in the salty ocean.