Investigating Genesis

by Stephen Caesar

Evolutionists claim that animals, when continually exposed to negative situations or attacks, evolve defense mechanisms to overcome these assaults. A common example is parasitism: Darwinists argue that, over the eons, animals that habitually fall victim to parasites evolve into creatures with better defense mechanisms, while parasites evolve improved methods to parasitize their evolving hosts. This thinking can be found in Natural History magazine, which claimed that a host's immune system, an exquisitely precise system of defense brought about by the evolutionary pressure of parasites, will do its level best to stave off the invasion. But host organisms have evolved other kinds of warfare as well: they can enlist other species to help them; they can medicate themselves; they can even program their unborn offspring for life in a parasite-ridden world (Zimmer 47).As effective as some of these counterattacks may seem, parasites - not surprisingly - can evolve counter-counterattacks (Ibid. 49).

The problem with this theory is that no scientist has ever seen a host animal develop a new defense mechanism causing it to evolve into a higher life-from; similarly, no one has ever witnessed a parasite develop a new, improved attack method that ultimately resulted in its transformation into a new species. If this occurred, it would be "macroevolution" - the development of lower life-forms into new, more highly-developed species. What scientists have actually seen is "microevolution" - small changes within a single species in response to external factors, giving the animal an increased ability to deal with these factors but not creating a new, higher life-form.

Experimentation on fruit flies has proved this, while no proof has ever been shown for macroevolution into new species. A. R. Kraaijveld of Britain's Imperial College of Science, Technology and Medicine conducted an experiment in which he permitted parasitic wasps to attack a group of fruit flies from one species. The attack resulted in the deaths of 19 out of 20 host flies. Kraaijveld then bred the survivors among each other. The next generation was attacked, and Kraaijveld bred THOSE survivors, etc. The attacking wasps were kept separate from the flies (Kraaijveld allowed them to live off another fly species in a separate container) to preclude the possibility that the wasps were evolving along with the victimized flies. Within five generations, the resistance rate of parasitized flies increased from 1 in 20 to 12 in 20 - that is, from 5% to 60% (Zimmer 49-50).

Darwinists argue that, given enough time, with the wasps constantly attacking them, the flies would eventually evolve into a new, superior species. Not so, Kraaijveld showed. Natural History stated that in later generations, the resistance remained at 60 percent. Why didn't it rise to 100 percent, creating a race of perfectly immune flies? Well, fighting wasps is costly. Kraaijveld set wasp-resistant flies in competition for food against regular flies and found that they fared badly. They grew more slowly, died young more often, and, if they survived to adulthood, were smaller. Evolution doesn't have an infinite arsenal to offer host organisms, and energy spent on one thing is not available for something else (Zimmer 50).

The "evolution" mentioned by Natural History is clearly microevolution within a single species. As useful as this mechanism is, it is undeniably limited - it does not create a new, more highly-evolved species, and it doesn't even create a 100% wasp-resistant fruit fly. Worse, it produces smaller, weaker, shorter-lived creatures, rather than more robust individuals on their way to becoming a new, improved species. Microevolution within a single species is a scientifically proven fact; macroevolution from a lower species into a higher one is sheer speculation, and is disproven by Kraaijveld, who demonstrated conclusively that small adaptations are strictly limited to less-than-complete improvements within a life-form.


Zimmer, Carl. (2000). "Attack and Counterattack: The Never-Ending Story of Hosts and Parasites." Natural History 109, no. 7.

Stephen Caesar is currently pursuing his master's degree in anthropology/archaeology at Harvard University. He also serves as adjunct professor of literature at Newbury College in Massachusetts.

He is the author of the e-book The Bible Encounters Modern Science, available at