Only fourteen phyla have appeared on Urantia, the fishes being the last, and no new classes have developed since birds and mammals.  The greatest event of all was the sudden appearance of the fish family. 
110,000,000 years ago marked changes occurred in the fish family, a sturgeon type first appearing, but the ferocious sea serpents, descended from the land reptiles, still infested all the seas, and they threatened the destruction of the entire fish family.  The Neanderthalers made holes in the ice covering the northern rivers and thus were able to spear the fish which came up to these vents.  Early units of barter were fishes or goats. 
Said Jesus: If your son needs a fish, will you give him a watersnake just because it may chance to come up in the net with the fish and the child foolishly asks for the serpent?  Risen Jesus directed apostles from the shore to cast the net. 
It is not strange that you have a record of Peter’s catching a fish with a shekel in its mouth. The reality is that Jesus paid the tribute without resorting to any artifice.