Annual Killifish

Annual killifish are some of the most colorful, beautiful fish in the world. They are wildly popular in the aquarium hobby due to their brilliant colors. However, there are a lot of other reasons to love annual killifish, many of them related to the origins argument.  The intricate design that characterizes these annual killifish is something that continues to be investigated in the secular scientific community. While not exhaustive, this article will briefly examine some of the characteristics of these annual killifish and explain how they fit into a creation model.

Annual killifish are known as annuals because they live in the adult stage for a very short time. One species lives for mere weeks in the wild, while others live for a few months. These short lifespans occur because of the wild habitats these fish live in, though in captivity they still have short lifespans. They live in small, seasonal pools that only have water during the wet seasons. Interestingly, the fish have genes on their sex chromosomes that control the lifespan. It is possible these genes also control the speed of maturation.  The fish lay eggs in the wet season that are left in the pool once it dries up.  When the eggs are formed, they develop until the pools dry out. Once the pools dry out, they go into a special state that prevents dehydration.  They dehydrate so slowly, that some of these eggs have been successfully hatched after three years of being out of the water.

The eggs do not hatch on a timer. They wait for specific environmental conditions. Once the water has dried out, the eggs go into their developmental pause state. They will not come out of this state until they sense the right environmental conditions. Exactly what environmental conditions are required are not completely known.  Temperature is involved, as is moisture. However, the exact mechanism by which the eggs detect the environment is unclear. They are able to sense it, but how an egg is able to do that is still unclear.  Interestingly, new research has discovered that the embryos do not age while they are in developmental pause. This is done by turning genes on and off in the embryo. Metabolism is repressed, but muscle maintenance and diapause are maintained. This requires very specified targetting of gene regulation.

These quick living, long incubating killifish present intriguing problems for creation and evolution models. Evolutionists have no explanation for such an origin of annualism in killifish. They postulate, based on phylogenies, that annualism evolved at least twice. However, this is quite difficult. Annualism requires the pre-existence of the diapause mechanism, as well as the rapid maturation of adults.  These both must be in place. However, diapause is an incredibly complex mechanism that we do not completely understand yet.  A mechanism to evolve this must be postulated before claiming is has evolved and, as yet, I have had seen no evidence of anyone trying to do this.   If they have, I would like to see it, but I suspect they cannot, as no other killifish that I am aware of has anything similar.

Creationists have their own problems with these annual killifish. Because they are alive under the Biblical definition, the fact that they have such short lifespans would not fit the “no death before sin” requirement of the Scripture. Obviously, they did not die before the fall. This leaves creationists with some options. The killifish could have had genes for lifespan broken as a result of sin which caused them to live much shorter lives. They would then have been stuck in these small pools after the flood, leaving them in the habitats they occupy today. Alternatively, the genes for rapid maturation could have been turned off prior to the flood and been expressed only in a post-flood world, the idea of mediated design. When these killifish were stuck in small pools in a post-flood world, they would have thrived in the absence of predators.  Either of these explanations could work.  They both explain the diapause mechanism equally well as something built into the killifish from the beginning. This is a much better explanation than what evolution offers.  Creationists are much better equipped to explain the origins of these annual killifish than evolutionists.


We have a whole video presentation on this topic. You can view that here


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