The jaw of Teinolophos trusleri catches the ear bones in the act of separating from the jaw.
Posted on 02/11/2005 6:49:09 AM PST by PatrickHenry
Triple bone structure arose independently in platypus and humans.
Listen up: mammals seem to have evolved the delicate bone structure of the middle ear at least twice. The surprising discovery comes from a fossil, found off the southern coast of Australia, that belongs to an ancestor of the platypus.
Modern mammals are unique among vertebrates for possessing three tiny bones in the middle ear. The malleus, incus and stapes (commonly known as the hammer, anvil and stirrup) work as part of a chain that transmits sound towards the skull. Birds and reptiles have only one bone to perform this function.
Because the mammalian arrangement is so complex, scientists believed that the set-up had evolved on just a single occasion, in an ancestor that gave rise to placental animals (including humans), marsupials and monotremes (such as the duck-billed platypus).
All this changed when James Hopson, a vertebrate palaeontologist at University of Chicago, Illinois, took a trip to Australia. There he met a team of researchers including Thomas Rich of Museum Victoria in Melbourne.
The jaw of Teinolophos trusleri catches the ear bones in the act of separating from the jaw.
Rich and his colleagues had recently unearthed a fossil of Teinolophos trusleri, an ancestor of modern monotremes that lived 115 million years ago. "He said he had some new Teinolophos specimens and when he showed them to me I almost fell off my chair," says Hopson, an author of the study, published this week inScience [Rich T. H., et al. Science 307, 910 - 914 (2005)].
Hammer time
Palaeontologists believe that the middle-ear bones of modern mammals once belonged to the jawbone and later separated to adopt their present location. This is supported by the fact that the middle ear's bones associate with the jaw in the early development of modern mammalian embryos.
What makes theTeinolophos specimen surprising is a large groove in its adult jawbone, which indicates that the smaller bones had not yet detached.
Teinolophos lived after monotremes split from the placental and marsupial mammalian groups. Its jawbone structure, along with its place in the evolutionary tree, hints that a common ancestor to all these mammals lacked the special three-bone ear structure.
This means that natural selection must have driven the same rearrangement in independent groups, after the monotreme split. "Some embryologists had the idea that it might be convergent but nobody really believed this," says palaeontologist Thomas Martin of the Senckenberg Research Institute in Frankfurt, Germany. "I was quite shocked when I heard that such a complex morphological transformation happened twice."
The discovery will compel many experts to rethink their appreciation of mammals' common evolutionary heritage. "Until now it was considered to be one of the most important shared derived characteristics of modern mammals," says Martin.
yeah...... ?
You were always an easy swoon. Think of it this way.
In evolutionary terms, it forces us to assume one of two things we would consider unlikely--the same thing evolving the same way twice, or some kind of reversion against the seemingly logical fitness trend.
What does the same finding look like from the Design viewpoint? 80 million years after the time we thought God gave all mammals high-quality ear bones, it turns out that for some reason He still hasn't got around to giving the ancestors of the platypus and echidna the good ears.
But later He did provide them because the platypus and echidna have them now. Hmmm?
Was He negligent or malicious? What's He got against one-holer egg-layers?
Before you start, I realize such questions cannot be asked of ID. The relevant quotes:
ID is a scientific theory for detecting purpose and teleology in nature. But don't ask us what that purpose is, because that's a religious question that's separate from ID.That's satire, of a sort, but the points it makes exactly illustrate why ID is not science and has nothing, nothing, nothing to offer mankind to advance our knowledge....
Darwinism can't explain the evolution of life in every single detail, therefore it's wrong. But don't ask IDists to explain these things, because that's not the kind of theory ID is. [7]
...
If a living system looks well designed, it's evidence for ID. If it looks poorly designed, that's just because we have no way of knowing what constitutes good and bad design.
...
A good scientific theory like ID should be vague and ambiguous, and refuse to propose any specific details about mechanism or history. Some unspecified being "designed" something, somewhere, at some point in time, somehow, is a perfectly good explanation.
The argument from design is not a theological argument, because we aren't necessarily talking about God. But any rebuttal of the design argument is theological, because it requires us to say "God wouldn't do it this way", and this is not legitimate. [16]
"The Quixotic Message", or "No Free Hunch"
Sorry, I won't be so contemptuous then. It is just that scientists who debate creationists keep hearing the same old debunked arguments over and over. It gets frustrating.
Actually, a chromosome number change would probably indicate a wider divergence than species. For instance, a piece could break off, but not change the genetics and still be the same species or a chromosome pair could duplicate and not change anything, but be there to mutate and eventually become active.
Or the whole chromosome set could duplicate without causing any infertility. Also remember that chromosome number changes in asexually reproducing organisms would immediately result in a new species.
Races are not sharply defined. The variation in genetics is so slight it is almost unimportant.
It does allow us to trace migration patterns, although even that is getting pretty difficult now. I object to even calling people different races. It is a divisive and unnecessary thing to do.
Selection for vitamin D is obsolete now with modern vitamin supplements and indoor living.
Please don't make all those silly comments that show you no nothing about biology. I can't believe you are really that uneducated in biology, yet want to get on with scientists and argue about it.
Scientists use micro and macro to describe technicalities. It is the same process of allele change.
Nope, just another common design
Well, you got one thing right. Congratulations
Scientists don't care what you think the Bible says. They only care about data that correlates with theories and hypotheses. If it doesn't correlate, they discard the idea they are working on and investigate an alternative.
When people moved up to the colder climes, they did not "know" they were going to turn white. Also, because the people who did first inhabit various areas were probably very small groups, you would have the whole population developing characteristics like the founding population as far as looks and stature.
But it is the whole population that gradually changes in evolution, not individuals. If you wanted to figure out who is the "most evolved", we already know the answer to that. The black races in Africa have the most alleles at the various loci and are the most evolved. In fact, the bulk of genetic diversity is carried by the blacks in Africa.
Do you have any scientific evidence that anything is designed by an intelligent designer?
Or are you saying that evolution designs things sometimes in a common way?
Yep.
Well here you have the same feature showing up in separate species and everyone agrees it's not a feature that those species share with a common ancestor.
To Creationists, when we see common advanced features showing up in separate biological lines, it is evidence of a common designer.
Evolutionists interpret that as "somehow genetics must be predisposed to developing the same feature".
It doesn't matter how hard and obvious the evidence for design is, the evolutionists will say, "there must be some natural process that doesn't include a designer that accounts for this."
"Well here you have the same feature showing up in separate species and everyone agrees it's not a feature that those species share with a common ancestor. "
All new features that appear are not shared with a common ancestor. Using your logic, all species would be immutable, which is what creationists think in the first place. So if it does change, "God did it"! If it does not change, "God did it"! Not only are you assuming your conclusion, you aren't being consistent.
"To Creationists, when we see common advanced features showing up in separate biological lines, it is evidence of a common designer. "
The actual evidence is that platypus is an example of a transitional branch. It has characteristics of both a reptile and a mammal. Different types of eye designs occur in separate branches. In fact, humans have a bad eye design. The receptors are facing backwards and there is a big blind spot. Other animals like hawks or eagles have a much better design. To infer that God would design Man in an inferior way goes against everything fundamentalist literalists believe.
"Evolutionists interpret that as "somehow genetics must be predisposed to developing the same feature". "
Not somehow! Natural selection always selects for survival. Hearing a predator approach is a necessary aid to survival. There is no reason the two could not have evolved similarly. You have already been given wings on bats and birds as an example. More study is needed on this new discover to verify it either way, in any case. It sure isn't going to be anyone at Discovery Institute that finds out how this development occured. They already "know" it was designed. LOL
"It doesn't matter how hard and obvious the evidence for design is, the evolutionists will say, "there must be some natural process that doesn't include a designer that accounts for this."
We have identified the process. It is called evolution through natural selection and other mechanisms. It is up to your side to present evidence to the contrary, not just make up stuff out of whole cloth or quote Bible verses.
Did you say the Platypus was the perfect branch animal? ROFLMAO. The Platypus has always tied evolutionists in knotts. This egg-laying, reptile, mammal with advanced electrical sensitivity is not supposed to exist according to evolutionary theory.
Did you just say that God designed man inferior to the eagle? ROFLMAO - You're killing me!!!. Tell me have eagles dominated man, or has man dominated eagles? You are implying that fundamentalists think man must be superior to every creature in every way. That's obviously not true.
And your human eye example is not valid either. The human eye is designed exactly the way God required it.
So on this thread, you link an ICR page with the following:
In reality, there is nothing in the fossil record to indicate that the platypus was ever anything other than a platypus. It is not a living ‘transitional’ form.For one thing, there is and was alredy more fossil evidence for the descent of monotremes than ICR is allowing. But the main thing is that you really can't lawyer on the differences between the old monos and the modern ones if you're going to follow the ICR line here. Significant differences are not allowed to exist. That's talking point number one.
So you're going to stop linking that article until somebody gets your stories all straight, right?
(BWAHAHAHA! Just kidding. You have no story. You're clearly not even paying attention.)
If you scroll to the bottom of the same link from AIG not ICR, you find these comments:
So you're going to stop linking that article until somebody gets your stories all straight, right?
Gratuitous appeal for censureship. I suspect your real issue with that article isn't it's comments on the Platypus but rather the following observations that blows away several of evolutionist's long standing arguments.
If I waited until evolutionists had their stories straight before I published creationist writings that blow them away, I'd have to wait so long, that evolution really could happen.
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