The Illusion Of The Cladogram

From the February 26, 2013 eNews issue
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Most of modern scientists assume that all life today evolved from single-celled organisms over the past several billion years. Since that assumption is pretty settled for the majority, biologists don’t bother questioning it. Instead, they assume it to be true, and spend time trying to figure out the evolutionary relationships of animals. What is the nearest common ancestor of both the frog and the newt? What are the ancestors of modern birds and how did they gain the ability to fly? How is this animal related to that animal, and where do they both fit in the evolutionary family tree?

Enter cladograms. A cladogram is simply a branched, tree-like diagram that is used to put evolutionary relationships in order [see references below]. Plants or animals are arranged along the branches according to the order in which they evolved from common ancestors.

Cladograms can be useful in sorting out closely related creatures… provided there actually is a relationship.

The study of cladistics is based on the concept that animals with similar structures and body parts are related. All vertebrates have a backbone, therefore evolutionists assume they all descended from a common ancestor with a backbone. Organisms are placed onto different
branches based on similar characteristics, called “characters”. Characters might include number of toes or number of sacral vertebrae. They might be, “has a jaw” or “chisel-like teeth”. Characters can get very specific, like “Bifurcated neural spine in cervical vertebrae”. The more similar characteristics different organisms have, the more closely they are considered related.

It would be nice for evolutionary theory if the taxa being placed on a cladogram lined up nice and neatly, step-by-step. But, that’s often not the case. Let’s say organisms A B and C are being ordered on the cladogram based on four different characters. If A had characters #1 and #2, B had characters #1, #2, and #3, and Organism C had characters #1, #2, #3, and, #4, it would be reasonable to say that C evolved from B, and B evolved from A in neat and tidy single-transition steps.

In real life, cladograms are not so simple. What if organism A has characters #1, #2, and #3, B has characters #1, #3, and #4, and C has #2 and #4? Which organism came first? Which came second?

If A is presumed to be the oldest organism of the three, then a significant bit of wriggling has to be done to demonstrate an evolutionary relationship; C has to lose characters 1# and #3, B has to lose character #2, and B and C both need a hypothetical transitional ancestor who possesses character #4. If you make C the oldest organism of the group, you have the same kinds of problems. Any way you work it, at least one organism has to lose a character and gain another for them to have been connected in the evolutionary past.

The loss or gain of characters is called a “transition”. In making a cladogram, all the possible arrangements are worked out, and the arrangement with the fewest total transitions is called "parsimonious".

Cladograms are an excellent tool for categorizing organisms according to shared and unshared characteristics. They cannot prove evolution, though, for several reasons:

1. Cladograms are notably free of true transitional forms. They are full of organisms with alleged common ancestors, but those common ancestors are never available for examination. In his article "Creationists Are 'Liars' (?)", Tas Walker analyzes a cladogram by Kevin Padian, and points out: the serious dearth of true transitional forms available for the diagram (after 150 years of looking for them.):


"So, does this diagram demonstrate that evolution is a fact as Padian claims? Let's look at the evidence. Is there evidence for the animals shown on the tips of the cladogram? Yes, lots of it. We have many examples of ray-finned fish, lungfish and living tetrapods. And we have fossil evidence of the other animals shown, such as tiktaalik. So the evidence exists and it is at the tips of the cladogram, or the tips of the bush.

"Do we have evidence of the common ancestors that are indicated by the intersection of the lines on the cladogram? For example, do we have evidence of the common ancestor that gave rise to the living tetrapods and fossil tulerpeton, as required by the intersection of their lines? No, we don’t. What about where the other lines intersect, do we have examples of those common ancestors? No, we have none at all."

Walter ReMine notes something similar in his book The Biotic Message:

"Illusion is created with tree-structured imagery, such as cladograms and phenograms. These are said to be evidence for evolution, but they do not identify a single ancestor-descendant relationship."

Evolutionists will say that certain characters are more prone to rapid evolutionary change—change that hasn’t been preserved in the fossil record, or are prone to converge with unrelated lineages, or have simply not yet been found just yet. The reality is that these scientists are still making up reasons for why they don’t have all the transitional forms they’d hoped for.

2. Cladograms give the illusion of relationship without any real evidence. While evolutionists seek to find the most "parsimonious" path of evolution when constructing a cladogram, they are still choosing which characters to compare—and therefore are placing organisms in a specific order on the diagram—according to their opinions.

Four cladograms constructed by four different scientists can give four different results.

In Padian’s cladogram on the origin of tetrapods, he shows the number of digits on the limbs of organisms in the lineup drop from 8 digits to 7 digits to 6 digits. If one just read that on paper, it could sound convincing. Yet a good look at the actual limbs that those 8,7, and 6 digits belong to show three very different skeletal structures. The humerus bones of the creatures get fat, then thin, then fat again. The radius and ulna bones go from relatively small, to large, then back to small and thin again. There are other ways in which these animals could be logically arranged.

(That these bones even have the names “humerus” or “radius” and “ulna” is a human decision, an effort to find similarities between all vertebrates. The massive differences between the creatures, like the fact that the “distal elements” of the various organisms are all quite distinct from each other, doesn’t seem to bother Padian.)

3. It’s nigh impossible to falsify a cladogram, because reversals are allowed. One organism in the order can gain a character, the next can lose it, and the next one can pick up that character again in order to make the cladogram "work". As John Jackson points out, "Lineages of animals have a way of evolving a feature, then removing it, and then re-evolving it again, in a way they have often had to be spoken to about."

Evolutionists who accept evolution as a fact a priori may not have a problem with reversals, because they believe that evolution is a driving force in nature. But for anybody skeptical of Darwinian evolution’s ability to produce brand new characters in the first place, reversals present a massive problem. To insist that the same character has evolved independently in different creatures, not just once but twice or three times, comes off as absolutely ludicrous. And since it can’t be proven by the fossil record, there is no legitimate scientific reason to accept it.

Cladograms can be a useful tool in categorizing animals, especially those that are truly closely related. The genetic code obviously allows plenty of variability for the adaption of plants and animals to different environments. However, cladograms only prove distant evolutionary relationships to those who already believe that organisms are all ultimately related. If one believes that the similarities between different plant and animal groups are due to specific engineering by a great Designer, then cladograms don’t prove much.


References
• Padian's Cladogram On The Origin Of Tetrapods - GeoTimes
• Problems With The Use of Cladistic Analysis In Palaeoanthropology. - US National Library of Medicine
• Does A 'Transitional Form' Replace One Gap With Two Gaps? - The Journal Of Creation
• What Is Cladistics? - Mike Taylor
• Birds of a Feather - Science Against Evolution
• Basics of Cladistic Analysis - George Washington University