I think one of the most dangerous things to do in life is to assume things to be true just because other people believe it's true. Adults often get annoyed at children who ask one too many "why" questions. Why is that? I've found the case to generally be because they don't know the answers, and they could care less why. "That's just the way it is," they would often say. So, I side with the children. I applaud their curiosity and inquisitiveness. And I hope I never lose that, and I encourage everyone to never lose that. When we start taking things for granted, we stop thinking. And when we stop thinking, we start believing anything. If only Truth was determined by majority vote, right? Well, it's not. And therefore, just because 90% of the world believes that in a crash between a mortal human and a train, the man would win, that does not mean the man would actually walk out of that crash alive. In fact, if he did, people would gasp and call the event a miracle.
In science, to test a theory, the process involves 3 general steps: 1) We make an observation about something (say, Why do cancer cells proliferate better than normal cells?); 2) we make a hypothesis about the observation (say, Cancer cells proliferate better because they can circumvent signals to die); and then 3) we create models to best reflect the natural environment so that we can conduct experiments to test whether our hypothesis is correct.
The key word here is "model." The model is not the real thing. For example, a drug tested in a mouse model may work beautifully, but when it is administered to humans, the drug no longer performs as expected. Going back to the cancer hypothesis above, many experiments are done in cell line models or animal models. As a fellow researcher, I can assure you all that we do our best to use models that best reflect reality, but at the end of the day, there are limitations. The easiest way to think about those limitations is this: In terms of cancer drugs, testing in humans would be testing in THE natural environment. Obviously, that is not morally possible. Even if it was, certain humans react differently to the same drug. This means, even if we are able to run experiments in humans, the results are at best an average, expected result. It may work beautifully for individual A, it may not work for individual B, and it may end up killing individual C. Hence, no matter how we look at science, every scientist is well aware of the limitations of their experiments. If they are not, then I would not trust any conclusion they draw from their results.
Why do I bother talking about this? The article below discusses the theory of evolution. We come across words like, "assumptions." We may not think too much of it and just keep reading right along, but I'm asking us not do that.
Assumptions are an inevitable part of creating a model. When scientists construct a model to test hypotheses, we must make assumptions in order for the model to work. Going back again to the cancer problem above, by testing drugs in mouse models, we're making the assumption that drug metabolism in a mouse is the same in a human. There is nothing wrong with making assumptions, as long as we take them into consideration when we interpret our results. For example, if the drugs worked in a mouse but not in the human, we don't immediately conclude the drug doesn't work. We remember that mice and humans are different, and we then seek what is preventing the drug to work in humans. If we can discover the reason, we may potentially discover another molecule to target in the treatment against cancer.
As we read the article, I ask that we ask questions. Ask a lot of why questions. Think about the assumptions these models are making, look at the data provided, and ask "Would I come to the same conclusions?" Why or why not?
One of my professors once said that experimental data are meaningless. It is our job as scientists to interpret those data into meaningful conclusions. Otherwise, data are nothing but numbers and statistics. What this means is, if scientists do not objectively interpret experimental data, the conclusions they come up with can be dangerously misleading. And if the general public just believes anything handed to them by scientists, then scientists can easily deceive the public and move crowds to where they want them to. (Examples: Do cellular phones cause brain tumors? Does drinking diet soda cause cancer? Think critically and look at the experimental data. Remember to keep the assumptions made about the models in mind. And you will discover the answer yourself.)
Enough of my preamble, let us analyze the article below:
The Illusion Of The Cladogram
from the May 29, 2012 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. 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. (Me: This is another way of stating an assumption of the experimental model!) 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.
• 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
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