Some species can be defined as “mosaic.” In other words, that they possess a combination of features from two other species. These species are particularly useful, revealing evolutionary relationships between organisms. Watching traits present in a later species emerge in an earlier creature, changing the average early creature to become more and more like the later form is a good indication there’s an evolutionary relationship being observed.

But that’s not the limit of their usefulness. They can help show which of the later species’ traits first emerged, how they changed and so forth. For example, it was thought that various changes to the human hip were the product of adapting to large brained babies. Yet Australopithecus sediba had many of these hip adaptations despite the fact its brain wasn’t much bigger than a chimps.

Mosaic finds are particularly prevalent in the human fossil record, with several species appearing to be “partway” between two others. Archaic Homo sapiens, for example, are intermediaries between us and Homo erectus. The aforementioned Australopithecus sediba is a mosaic of Australopithecus africanus and later Homo (such as Homo erectus).

As you may begin to realise, these mosaic forms are not only useful scientific discoveries but sterling evidence for evolution as well. They are the “transitional forms” creationists are always demanding yet claiming are never found. Unfortunately, the mosaic nature of these fossils leaves creationists with an out. Since they do contain a mixture of two species the scientific descriptions go “look how feature X looks like species X and look how feature Y looks like species Y.” A creationist intent on obscuring the transitional nature of these fossils could only focus on the first part of the sentence, going “this isn’t a transitional form, it’s just a member of species X!”

For an example, let us return to Australopithecus sediba. The paper which first described the find is “Australopithecus sediba: A New Species of Homo-Like Australopith from South Africa” and notes

The closest morphological comparison for Au. sediba is Au. africanus, as these taxa share numerous similarities in the cranial vault, facial skeleton, mandible, and teeth. Nevertheless, Au. sediba can be readily differentiated from Au. africanus on both craniodental and postcranial evidence….these exact differences also align Au. sediba with the genus Homo

And which part of this description does Answers in Genesis, a multi-million dollar creationist organisation, quote when they attempt to dispute the fact Au. sediba belong in the human family? Well here’s an extract from their article “The Problem with Australopithecus sediba

The Berger team also write: “The closest morphological comparison for Au. sediba is Au. africanus.” My own cast of an Australopithecus africanus skull confirms its likeness to Australopithecus sediba, and pictures of such skulls confirm the same. And Australopithecus africanus also closely resembles a modern chimpanzee

Au. sediba is just Au. africanus, and since Au. africanus is just a chimp we can ignore the whole thing! Including the bits that describe how Au. sediba differs from Au. africanus, rendering our chain of reasoning invalid (even assuming Au. africanus was just a chimp).

But surely this is just a one off! Well, in “The Truth about Human Origins“, a book from ‘Apologetics Press’ the authors discusses Ardipithecus ramidus.

The authors of the paper in Nature described the cranial fossils as “strikingly chimpanzee-like in morphology”. The pieces of arm bone were described as exhibiting “a host of characters usually associated with modern apes”.

The paper itself, from when the species was still called Australopithecus ramidus, actually said

The specimen also shows a host of characters usually associated with modern apes, including a strong angulation of the distal of the distal radial articular surface due to a large styloid process, a strong lateral trochlear ridge on the distal humerus (also seen in some A. afarensis), and an elngate superoposteriorly extended lateral humeral epicondyle. The Aramis arm diverges from the African ape condition in other features

As if the second, omitted sentence isn’t bad enough note the few words from before their chosen quote they ignored. “The specimen also shows.” Sure enough, just before this paragraph the article noted various non-ape like characteristics.

The arm displays a mosaic of characters usually attributed to hominids and/or great apes. From proximal to distal, probable derived characteristics shared with other hominids include an elliptical humeral head; a blunt proximally extended ulnar olecranon process surmounting a straight dorsal upper shaft profile; an anteriorly orientated trochlea notch; and an anteriorly facing ulnar brachialis insertion. The specimen also shows a host of characters usually associated with modern apes

Immediately proceeding and following the chosen quote are descriptions of non-ape characteristics completely omitted so as to make Ar. ramidus seem more like an ape than it actually is. This lie of omissiom forms a crucial point later on, with them arguing

A[ustralopithecus]. anamensis is “more or less” a hominid, even though it is similar to Ardipithecus ramidus (which, as Donald Johanson admitted, possesses “many chimp-like features”).

Now, my point here isn’t to try and poison the well or guilt by association to persuade you to dismiss all creationist quotes or arguments as unfounded. I’m simply trying to point out that mosaic or “transitional” forms are, by their very nature, open to being misquoted to lend unfounded credence to a position.

They’re not arguing against the non-ape like features in these hominins or presenting other valid reasons why they should be considered apes, they’re just completely ignoring the issue. Whether you’re accept creationism or evolution, hopefully you can appreciate that is wrong. So I urge you, whether you’re a creationist or not, when presented with an article on how a mosaic find is “just an x” – especially if a quote is used to lend credence to this idea – be skeptical. Don’t dismiss it but investigated it if possible. At the very least take it with a mountain of salt.

Related posts



Categories: Creationism

16 Comments

R. K. Sepetjian · 30th July 2012 at 9:13 pm

Adam, I would like to think our strongest bond is a pursuit for truth.

1) I don’t think anyone should use deception to make a point. Which is why I can’t understand why they won’t remove lies in the textbooks that support evolutionism such as the fetus supposedly having gill slits like a fish which was proven wrong in 1875 or that humans and animals have vestigial organs, just to name two. I can’t speak for the textbooks by you, but every U.S. Science Textbook I have ever read offers these as proofs.

2) There is no “fossil record”. There are a bunch of bones in the dirt on which people have placed their assumptions.

3) No bone or fossil found in the ground is evidence for evolution. For starters, you don’t know that that creature had ANY kids, much less DIFFERENT kids. And why would you believe a bone in the dirt could do what animals today cannot; bring forth a different kind of animal which has never been observed.

4) What is your definition of species?

    gergo · 31st July 2012 at 7:44 pm

    1) Can you name a few of the books you are criticising?

    Quoting from Campbell, Reece, et al., “Biology, Eighth Edition”, page 700: “In all chordate embryos, a series of pouches separated by grooves forms along the sides of the pharynx. In most chordates, these grooves (known as pharyngeal clefts) develop into slits that open to the outside of the body. […] In tetrapods, the pharyngeal clefts do not develop into slits. Instead, they plan an important role in the development of parts of the ear and other structures in the head and neck.” So this is a U.S. science textbook that does not support your statement.

    And regarding vestigial structures, page 463: “Some of the most intriguing homologies concern “leftover” structures of marginal, if any, importance to the organism. These vestigial structures are remnants of features that served important functions in the organism’s ancestors. For instance the skeletons of some snakes retain vestiges of the pelvis and leg bones of walking ancestors. Another example is the decreased size and loss of function in cetaceans’ hind limbs as these organisms faced the challenges of life in water.” So yes, this U.S. science textbook talks about vestigial structures. But what exactly do you think is wrong about this statement?

    2) There are a bunch of bones in the dirt of various ages spanning many millions of years and displaying changing characteristics over time. Finding relationships is a little more than just making unfounded assumptions.

    3) You might want to read a *good* textbook on evolutionary biology or Richard Dawkins’s “The Greatest Show on Earth”, which is chock-full of examples of organisms bringing forth different kinds of organisms over time. Even over time that can be observed within a human lifetime.

      R. K. Sepetjian · 1st August 2012 at 1:33 am

      Hi gergo!

      Great questions!

      1) Fetal Gill Slits:
      A. “Biology, A Journey Into Life”, Arms and Camp, 1991, p. 557

      B. Biology, 9th ed. New York: McGraw-Hill, 97.

      C. Glencoe Biology, pp. 770, 779, 787] (removed in latest edition)

      D. SPARKNOTES SAT II Biology 2004 Edition, pp.119-120

      E. Homework Helpers Biology, Evidence from Embryology, Distefano, p.155

      2) There is no such thing as vestigial structures. Vestigial organs are fully functional and many biologists and researchers have now shown that structures which were dismissed as inconsequential have important roles to play. For instance:

      A. The human tailbone is the anchor point for nine little muscles needed to support the colon, anchor the end of the spinal column, and perform several other functions.

      B. The whale does not have a vestigial pelvis. Those bones are anchor points for special muscles used during reproduction. The bones of the male whales differ from those of the female. Furthermore, there is no fossil evidence for loss of legs in whales.

      C. The spurs on the abdomen of some snakes are also used in mating. I have seen the snake skin of a fifteen-and-a-half-foot python. You could see the two little half-inch claws; each is attached to a tiny bone about two inches long. They are not remnants of legs.

      D. The human appendix serves as a part of the immune system today. It’s true that you can live without it. So what? You can live without both of your legs, both of your arms, and both of your eyes as well. That doesn’t prove you don’t need them. Removal of the appendix causes the rest of the immune system to work harder, that’s all. People without their appendix are more likely to live shorter lives and catch more diseases.

      *****Not to mention, even if these organs were vestigial, that is the OPPOSITE of evolution since you are losing NOT gaining genetic information or complexity.*****

      3) I agree that there are a bunch of bones in the dirt but I disagree that they span many millions of years. I believe all the fossils were deposited during the Flood, 4,400 years ago. Helps to make sense why most fish fossils are found with gills and fins extended, as though terrified right before being buried alive in mud.

      As I’ve mentioned already, in a court of law, you could never prove that a bone in the ground is anyone’s ancestor today and you certainly could not demonstrate that it had any kids much less different kids.

      4) Give me your BEST evidence of Macro Evolution–that one kind of animal gave birth to a different kind of animal.

        gergo · 1st August 2012 at 5:15 pm

        1) Could you give a more exact citation for the book you refer to as “Biology, 9th ed. New York: McGraw-Hill, 97”? My university library has several books by different authors of that title from that publisher. It would also be great if you simply quoted what it says about gill slits.

        2) I don’t know if what you say about the use of whales’ vestigial pelvis in mating is true, but even if it is, all the rest of their ancestors’ hips and legs is gone (and there *is* fossil evidence for that). This does not contradict evolution at all: Structures that were a hindrance to their new way of life were lost over time. You may call this lost complexity, I call it better adaptation to faster/easier swimming.

        3) Yes, mudslides are great for fossilization of whole animals. No, that does not mean that there was only exactly one giant mudslide 4,400 years ago. Mudslides happen all the time.

        4) My BEST evidence does not matter because I’m not a specialist, and because there is no single example that “dominates” all the rest in that if you were to disprove that, all the rest wouldn’t hold either. As I said, “The Greatest Show on Earth” has nice examples. Two I remember fondly are: (a) Herbivorous lizards introduced to an island where their preferred food plant was not available and no other lizards lived; within 20 years or so (I’m doing this from memory), their descendants preferred eating insects and showed many adaptations to their new diet. (b) Yeast cells (or bacteria? I don’t remember) in a long-term study accumulated several mutations that allowed them to digest a nutrient they couldn’t metabolize before.

        These might not be “kinds” according to your definition, but they do illustrate nicely how reproduction, mutation, and selection can work together to make new things happen well within human lifetimes.

    Adam Benton · 31st July 2012 at 8:30 pm

    1) Having never seen these books I can’t say whether you’re description. But I don’t mistrust you, so will simply note that many textbooks include an address where you can contact them to point out factual errors, spelling mistakes etc. Perhaps you could point out their error. Beforehand, however, please note that whilst there were several issues with the 1875 drawings, fabricated gill slits and vestigial organs are not one of them. Note this human embryo with gill slits (also called pharyngeal arches) and a tail!

    2) There are a bunch of ordered bones in the dirt*. You can predict where a fossil should be found based on its age because fossils appear in an order. That wouldn’t be possible were it just assumptions and assertions.

    3) You find two human bodies who lived 500 years apart. Unable to perform genetic analysis because of an inverse tachyon field, you can’t work out whether they’re related. So can you say nothing about their relationship? Of course you can. Whilst you might not know if the older find is a direct ancestor, you can clearly see its related somehow. Be it the brother, uncle or (very distant) cousin there is a relationship there. Direct ancestry can’t be determined, we can still work other things out. So that’s what we do.

    4) Producing viable young is a good rule of thumb when it comes to defining species but in reality it is a lot more complex than that, especially when you are dealing with subspecies.They can still interbreed and be viewed as distinct.

    Take this situation for example. All around one side of the ring the populations are distinct but can still interbreed, making them subspecies. Yet when they meet up at the top they can no longer interbreed, rendering them different species.

    But at the same time they’re sub-species, but also different species, but also…..gahhh! It’s confusing, and hopefully shows why the rule of thumb isn’t the best rule. Sadly, it is the best we’ve got.

      R. K. Sepetjian · 1st August 2012 at 1:56 am

      1) Largely answered above with gergo

      2) “You can predict where a fossil should be found based on its age because fossils appear in an order.”

      This is precisely the piece I do not understand. You see clams at the bottom and assume they evolved early, and you see birds and humans in higher layers and assume they evolved last. But don’t you see? That is exactly what you would expect to find in a worldwide Flood. The clams, which are already at the bottom of the sea would naturally get buried first. Birds which can fly and humans which are smart enough to seek higher ground would naturally avoid drowning until the absolute last minute. That is why birds and humans are mostly found in higher levels. Of course, should a bird fossil be found in the same layer as a marine fossil, it is quickly dismissed as insertion, etc.

      3) Sure, two HUMAN bodies are going to be related at some point down the line. That is different than Darwinian evolution which believes that dogs and bananas share a common ancestor or that all life evolved from lower forms.

      4) It sounds like you are saying if they are inter-fertile, then they are the same species. That’s not the case though. canis domesticus (dog) and canis lupus (wolf) are inter-fertile, but are different species. I have never heard a good definition for “species” which is why I prefer the word “kind”. The Bible says if they can “bring forth”, they are the same kind.

        Adam Benton · 3rd August 2012 at 7:21 pm

        1) Your discussion includes some references to gill slits/pharyngeal arches, yet as I mentioned humans do have such structures.

        2) This idea doesn’t stand up to more than half a second of scrutiny. I could bring up all the examples of stuff not fitting with this idea (like the clams mentioned elsewhere in these comments) but I shall restrict myself to one: plants. Like animals, plants also evolve over time. This evolution is also traceable via the fossil record. Are you suggesting that the newer, flowering plants were actually just able to run away from the flood faster than ferns?

        3) Not fundamentally. You look at two humans and know there’s some kind of relationship based on the various anatomical (and if possible molecular and genetic) similarities. You look at two species and apply the same reasoning.

        4) It is nice to see an actual definition kind provided, often a handwaving nonanswer is given like “it would be obvious to a 5 year old.” However, the archaic language of the Bible is quite opaque and it seems like two definitions could fit. Either its suggesting that creatures able to produce offspring are the same kind, which would mean that the issues with the definition of species are applicable to kind. The only real difference being that creatures able of creating hybrids are now considered the same kind, since “bring forth” makes no reference to fertility.

        Alternatively it is a reference to whether organisms have a common ancestor. This definition would work and circumvent many of the issues with species. That said, it would render the fond creationist criticism of “you never see a species changing kinds” moot. If kind is defined as a group of organisms with a common ancestor evolution does not say at some point this group will stop sharing a common ancestor. You would not expect them to change kinds.

        Some clarity as to what “bring forth” means would be greatly appreciated.

geoffrey neilsen · 31st July 2012 at 3:45 pm

On the pursuit for truth I concur.
Your main thrust is quite valid. I support what I perceive as your argument for presenting the facts in an unbiased and honest report – and your cry to attention for readers to beware.
However, as in almost all forums, the debate quickly becomes fogged.
As opinion, may I venture that in this instance of the investigation of the origins of humankind, the debate concerning the taxonomic definitions takes over? Perhaps we should return to science and drop the quasi-legal arguments?
PS. In reply to R.K.Sepetjian (and this is what prompted me to post)
1) OK
2) I like the description
3) That doesn’t really seem to make any sense as an argument
4) That question was directed at you, Adam
5) Ever heard of (and thought about) ‘deep time’?
written on a Tuesday.

    Adam Benton · 31st July 2012 at 7:58 pm

    I wish one could just focus on the science but alas, we live in a world where misquotes and rhetoric carry more weight with some than evidence. Pointing out that this criticisms are just misquotes and rhetoric is a necessary task.

R. K. Sepetjian · 1st August 2012 at 7:04 pm

@gergo:

1) “Could you give a more exact citation for the book you refer”

No. I made the point that every US textbook I’ve ever read used lies to support evolution. You went and found one that didn’t and tried to refute my claim. I came back with 5 examples verifying my claim. If I haven’t satisfied your curiosity, I never will. Therefore, there is nothing further to discuss on this point.

2) “I don’t know if what you say about the use of whales’ vestigial pelvis in mating is true”

It is. Study it out a little more. Please show me the fossil evidence for whale legs.

3) Mudslides happen all the time. Worldwide Floods do not. This point does nothing to advance your notion of a “fossil record.”

4) “My BEST evidence does not matter because I’m not a specialist,”

Naturally. This is how EVERY SINGLE exchange goes when I ask for evidence.

Me: “Show me evidence for evolution.”

They: “Oh, there’s tons of evidence.”

Me: “Okay, please show me one.”

They: “There’s so much evidence.”

Me: “Okay, show me one.”

They: You don’t understand how much evidence there is.”

Me: “Okay, can I please see some?”

AND THEY NEVER DO SHOW YOU ONE!

The Biologist thinks the Geologist has the evidence. The Geologist thinks the Anthropologist has the evidence. And the Anthropologist thinks the Biologist has the evidence! It’s like a shell game…but there ain’t a pea under any of them!

So a lizard is your evidence, huh?
So you started with a lizard and after evolution, you had….a lizard!

Thank you for demonstrating to all readers how religious this worldview really is.

    gergo · 1st August 2012 at 8:52 pm

    1) “I came back with 5 examples verifying my claim.”

    No. You came back with examples I cannot check if I cannot find them, and I cannot find them if you don’t tell me the authors’ names because “Biology” is the title of several different books by different authors published by McGraw-Hill. And now you refuse to tell me the authors’ names. I thought you weren’t into using deception to make your point?

    2) It’s in the books. Such as Campbell, Reece et al., “Biology, Eighth Edition”. You’ll find nice illustrations of intermediate forms between land-dwelling mammals and modern whales. You’ll also finds information on fossil evidence, including photos of fossilized skeletons, at http://en.wikipedia.org/wiki/Evolution_of_cetaceans

    4) Oh come on. I’m a computer scientist who only ever took two undergrad courses in biology. My limited knowledge of evolution is enough for you to dismiss all the research in this area in the last 150 years?

    And I cited two examples of how quick changes can occur due to selection even in short periods of time; naturally, these do not lead from a lizard to a mammal in 20 years. But imagine millions of years…

      R. K. Sepetjian · 1st August 2012 at 9:05 pm

      “But imagine millions of years…”

      And that’s precisely my point, gergo. The ONLY place macro evolution occurs is in the imagination. Having to imagine something happened is religious, not scientific.

Jim Thomerson · 1st August 2012 at 10:24 pm

Clams, bivalve molluscs, first show up in the fossil record sometime during the Cambrian. They have persisted to the present with some 9,200 living species. They have shells, and often live buried or attached, and thus have a better than usual chance of fossilization. They occur throughout the geologic column, particularly from the Triassic forward, and to say that they are concentrated at the bottom is not true. Incidentally, some of the larger fossil clams have been found with fish bones inside. Somewhere, a clam died this morning and is on its way to becoming a fossil, perhaps to be found by a paleontologist thousands or millions of years in the future

Jim Thomerson · 5th August 2012 at 9:58 pm

Here is a link to a discussion of what Darwin had to say about rudimentary organs. http://whyevolutionistrue.wordpress.com/2012/08/05/darwin-right-again-the-inner-ears-of-sloths-are-highly-variable/

R. K. Sepetjian · 8th August 2012 at 1:51 am

@Adam

“1) Your discussion includes some references to gill slits/pharyngeal arches, yet as I mentioned humans do have such structures.”

I resisted pointing this out originally, because I could not come up with a gentile way of conveying the message. But since you are insisting that the fetus has gill slits and a tail, you’ve left me little choice.

The human fetus DOES NOT have a gill slits or a tail.

The folds in the neck develop into bones in the ear and glands in the throat.

As a crusader for thorough research, I have to admit that I am a bit shocked that you don’t realize this was proven wrong back in 1874! Earnst Haeckel was convicted of fraud by his own University in Jena, Germany 138 years ago!

If your professors are still teaching that the fetus has a tail and gill slits, I would go straight to the Bursar and demand a refund because you are being lied to.

Ontogeny DOES NOT recapitulate Phylogeny.

For more: (http://sepetjian.wordpress.com/2011/10/29/does-ontogeny-recapitulate-phylogeny-refuting-embryological-%E2%80%9Cevidence%E2%80%9D-for-evolution/)

2) “This evolution is also traceable via the fossil record.”

Do you believe that humans evolved from a rock 4.6 billion years ago?

3) So you cannot conclude that two humans were ever related, but you believe that humans and apes are?? You have been sold a religion, Adam. And a bad one at that.

4) The Biblical use of “bring forth” ABSOLUTELY refers to offspring.

“And God said, “Let the earth bring forth living creatures according to their kinds—livestock and creeping things and beasts of the earth according to their kinds.” And it was so.” Genesis 1:24

You don’t have to like or use the word “kind” but as I pointed out, your definition for species is incorrect. Therefore, until you get a new definition for species, at least we’re on the same page with “kind.”

    Adam Benton · 9th August 2012 at 11:32 pm

    1) You seem to be labouring under the false impression that Haekel’s conclusions and drawings are the be all and end all of embryology. They are not. Whilst his images were broadly accurate, his conclusion that “ontogeny recapitulates phylogeny” was not and so modern embryologists have developed more accurate pictures and ideas. The ideas your attacking are over 100 years out of date.

    The (modern) point about the phyarangeal arches is that they’re the same structure in all vertebrates but they develop into different structures. Evolution has modified their development and final structure but not their starting state. At the early stages of development, they’re basically identical.

    2) No, humans evolved from a species of ape ~6-7 million years ago.

    3) No, you’re missing the point. You can conclude 2 humans are related, despite the fact that you can’t figure out if there is a direct connection between them. You don’t have to know if the older skeleton had a child or not. Similarly, you can conclude 2 species are related, even if you can’t figure out that a fossil you found had babies or not.

    4) If the capacity to bring offspring is the definition of kind, then your definition of kind is basically the same as species and so inherits all the same problems it has. Speaking of which, I looked into it and found that the problem you identified is non-existent. Dogs are labelled a sub-species of wolves (Canis lupus and Canis lupus familiaris) so the fact they can interbreed is not a concern for taxonomist.

Leave a Reply

Your e-mail address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.