One of the objections to the idea that various organisms living today have a common ancestry is that, while one may infer such a thing from fossil, structural, and molecular evidence, one can never actually see such processes of evolution happen because they would take millions of years, and thus human beings could never live long enough to see macroevolution directly. That would indeed be true if we could rely only on natural processes of random mutation and natural selection. But what if it was possible to accelerate the process of evolution, to use artificial selection and genetic engineering to test whether there are limits to how far evolution can go to a line of organisms?
First, we must consider that humans have already done artificial selection to plants and animals for thousands of years, resulting in higher food yields from those domesticated plants and animals we eat as well as various forms that have other purposes to us, including for companionship and for their beauty. Darwin used such cases of artificial selection as examples of evolution, and suggested that natural selection operated in a similar way. It stands to reason that we could use genetic engineering to both make greater changes to domesticated plants and animals and mimic natural selection as it may have happened over millions of years in the past.
Creationists have claimed that lines of organisms can evolve, but only to a certain degree; they could never go beyond the limits of a “created kind”. At present this is entirely an assumption based on dogmas drawn from the Bible. What we need is an experiment that could actually support or falsify that claim, and at the same time demonstrate evolution in action. And I have come up with just such an experiment.
It is common knowledge that crocodilians are distant relatives of birds, both being members of the Archosaur clade. Dinosaurs are also thought to belong to this same clade. My proposed experiment involves performing genetic engineering on crocodilians to see if one can turn them over several generations into dinosaur-like animals. One must note that while crocodilians are a sister group to dinosaurs and most are generalized in nature, birds are actual descendants of dinosaurs and most of them are highly specialized for flying. One might choose a rather unspecialized and flightless bird, such as an ostrich, for the subject of the experiment, or a typical crocodilian. The ostrich might be less suitable because to make a dinosaur-like creature from it would be both a backward step and would not be a spectacular enough change to demonstrate that there may be no limits to how lines of organisms may change in nature. Therefore, a crocodilian would be better. And in my judgment, the best possible subject would be the American alligator (Alligator mississippians) because it is unspecialized, readily available, and abundant, unlike some other crocodilian species, which are endangered.
Having selected our subject, we may proceed with the next step, which is to determined the entire sequence of the genetic code of the American alligator. After this is done, we then take a population of alligators and make a few changes to the alligator genes, the sort that could happen due to natural mutations. These changes may cause the offspring of the first generation of alligators to still look like members of the crocodile order, but with unusual traits that no current alligator or crocodile today has. Then we make a few further changes to the genes of the members of the second generation of alligators. We repeat this process for every succeeding generation until about a dozen or so generations of alligators have been produced, resulting in creatures that no longer even resemble alligators, but look like dinosaurs.
Anti-evolutionists may argue that while such an experiment may seem to show evolution in action, it would not prove that such changes can occur naturally, and would instead point to intelligent design. This argument, if its premise is accepted, would actually invalidate any experiment, since one could always claim that any experiment may not mimic exactly circumstances and processes that occurred millions of years ago. Also, the intelligent design claim would only be valid if we made the alligator to dinosaur leap in one generation, instead of taking a dozen or more generations as I am proposing.
If it turns out that in fact there is a mechanism which prevents genetic changes to a line of organisms beyond the limits of a “created kind”, then there may come a point in the experiment where attempts to make further changes to the alligator population fail and either the next generation members end up badly deformed or they do not change at all. After several attempts to make the changes have failed, the next logical step would be to find the mechanism and identify exactly how it works. We may then locate this same mechanism in many other species of animals and plants. And the discovery of this mechanism would put evolution as a valid theory to rest forever.
On the other hand, the success of the efforts to make dinosaur-like creatures from alligators would give vital support (but not absolute proof, for in science there is no such thing) to the idea that dinosaurs (and birds) could have evolved from very different animals naturally and would make Creationist claims look even more ridiculous than they already do.