…and this is a 
It's yet another transitional fossil! Are you tired of them yet?
Darwinopterus modularis is a very pretty fossil of a Jurassic pterosaur, which also reveals some interesting modes of evolution; modes that I daresay are indicative of significant processes in development, although this work is not a developmental study (I wish…having some pterosaur embryos would be exciting). Here it is, one gorgeous animal.
(Click for larger image)
Figure 2. Holotype ZMNH M8782 (a,b,e) and referred specimen YH-2000 ( f ) of D. modularis gen. et sp. nov.: (a) cranium and mandibles in the right lateral view, cervicals 1-4 in the dorsal view, scale bar 5cm; (b) details of the dentition in the anterior tip of the rostrum, scale bar 2cm; (c) restoration of the skull, scale bar 5cm; (d) restoration of the right pes in the anterior view, scale bar 2 cm; (e) details of the seventh to ninth caudal vertebrae and bony rods that enclose them, scale bar 0.5 cm; ( f ) complete skeleton seen in the ventral aspect, except for skull which is in the right lateral view, scale bar 5 cm. Abbreviations: a, articular; cr, cranial crest; d, dentary; f, frontal; j, jugal; l, lacrimal; ldt, lateral distal tarsal; m, maxilla; mdt, medial distal tarsal; met, metatarsal; n, nasal; naof, nasoantorbital fenestra; p, parietal; pd, pedal digit; pf, prefrontal; pm, premaxilla; po, postorbital; q, quadrate; qj, quadratojugal; sq, squamosal; ti, tibia.
One important general fact you need to understand to grasp the significance of this specimen: Mesozoic flying reptiles are not all alike! There are two broad groups that can be distinguished by some consistent morphological characters.
The pterosaurs are the older of the two groups, appearing in the late Triassic. They tend to have relatively short skulls with several distinct openings, long cervical (neck) ribs, a short metacarpus (like the palm or sole of the foot), a long tail (with some exceptions), and an expanded flight membrane suspended between the hind limbs, called the cruropatagium. They tend to be small to medium-sized.
The pterodactyls are a more derived group that appear in the late Jurassic. Their skulls are long and low, and have a single large opening in front of the eyes, instead of two. Those neck ribs are gone or reduced, they have a long metacarpus and short tails, and they've greatly reduced the cruropatagium. Some of the pterodactyls grew to a huge size.
Here's a snapshot of their distribution in time and phylogenetic relationships. The pterosaurs are in red, and the pterodactyls are in blue.
(Click for larger image)
Time-calibrated phylogeny showing the temporal range of the main pterosaur clades; basal clades in red, pterodactyloids in blue; known ranges of clades indicated by solid bar, inferred 'ghost' range by coloured line; footprint symbols indicate approximate age of principal pterosaur track sites based on Lockley et al. (2008); stratigraphic units and age in millions of years based on Gradstein et al. (2005). 1, Preondactylus; 2, Dimorphodontidae; 3, Anurognathidae; 4, Campylognathoididae; 5, Scaphognathinae; 6, Rham- phorhynchinae; 7, Darwinopterus; 8, Boreopterus; 9, Istiodactylidae; 10, Ornithocheiridae; 11, Pteranodon; 12, Nyctosauridae; 13, Pterodactylus; 14, Cycnorhamphus; 15, Ctenochasmatinae; 16, Gnathosaurinae; 17, Germanodactylus; 18, Dsungaripteridae; 19, Lonchodectes; 20, Tapejaridae; 21, Chaoyangopteridae; 22, Thalassodromidae; 23, Azhdarchidae. Abbreviations: M, Mono- fenestrata; P, Pterodactyloidea; T, Pterosauria; ca, caudal vertebral series; cv, cervical vertebral series; mc, metacarpus; na, nasoantorbital fenestra; r, rib; sk, skull; v, fifth pedal digit.
Darwinopterus is in there, too—it's the small purple box numbered "7". You can see from this diagram that it is a pterosaur in a very interesting position, just off the branch that gave rise to the pterodactyls. How it got there is interesting, too: it's basically a pterosaur body with the head of a pterodactyl. Literally. The authors of this work carried out multiple phylogenetic analyses, and if they left the head out of the data, the computer would spit out the conclusion that this was a pterosaur; if they left the body out and just analyzed the skull, the computer would declare it a pterodactyl.
What does this tell us about evolution in general? That it can be modular. The transitional form between two species isn't necessarily a simple intermediate between the two in all characters, but may be a mosaic: the anatomy may be a mix of pieces that resemble one species more than the other. In this case, what happened in the evolution of the pterodactyls was that first a pterodactyl-like skull evolved in a pterosaur lineage, and that was successful; later, the proto-pterodactyls added the post-cranial specializations. Not everything happened all at once, but stepwise.
(Click for larger image)
Schematic restorations of a basal pterosaur (above), Darwinopterus (middle) and a pterodactyloid (below) standardized to the length of the DSV, the arrow indicates direction of evolutionary transformations; modules: skull (red), neck (yellow), body and limbs (monochrome), tail (blue); I, transition phase one; II, transition phase two.
This should be a familiar concept. In pterodactyls, skulls evolved a specialized morphology first, and the body was shaped by evolutionary processes later. We can see a similar principle in operation in the hominid lineage, too, but switched around. We evolved bipedalism first, in species like Ardipithecus and Australopithecus, and the specializations of our skull (to contain that big brain of which we are so proud) came along later.
As I mentioned at the beginning, this is an example of development and evolution in congruence. We do find modularity in developmental process — we have genetic circuits that are expressed in tissue- and region-specific ways in development. We can talk about patterns of gene expression that follow independent programs to build regions of the body, under the control of regional patterning genes like the Hox complex. In that sense, what we see in Darwinopterus is completely unsurprising.
What is interesting, though, is that these modules, which we're used to seeing within the finer-grained process of development, also retain enough coherence and autonomy to be visible at the level of macroevolutionary change. It caters to my biases that we shouldn't just pretend that all the details of development are plastic enough to be averaged out, or that the underlying ontogenetic processes will be overwhelmed by the exigencies of environmental factors, like selection. Development matters — it shapes the direction evolution can take.
Lü J, Unwin DM, Jin X, Liu Y, Ji Q (2009) Evidence for modular evolution in a long-tailed pterosaur with a pterodactyloid skull. Proc. R. Soc. B published online 14 October 2009 doi: 10.1098/rspb.2009.1603
I should have mentioned that Darren Naish has a very thorough write-up on Darwinopterus!
Life Science
Comments
Posted by: Matt Heath
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October 15, 2009 10:27 AM
Yeah, but it's still a flying lizard thing. Where's the pteroduck??!!!
(not real)
Posted by: Nerd of Redhead, OM
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October 15, 2009 10:28 AM
Oooh, brainfood. Time for my midmorning snack.
I thought all fossils were transition fossils. Or did I miss the memo?
Posted by: mcbender
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October 15, 2009 10:34 AM
Not being a biologist, it's difficult for me to fully appreciate this sort of thing, but it's always great to see more "transitional forms" coming out of the woodwork. In addition to whatever insights they give us into evolutionary history, it's nice to have more ammunition for making creationists squirm (presuming you can get them to understand what you're talking about to begin with).
On the other hand, am I the only one who thinks it's a little tacky that they're incorporating "Darwin" into the pseudo-Latinate scientific names of all of these discoveries? I can understand why they're doing it... but it bothers me a little.
Posted by: Cycle Ninja
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October 15, 2009 10:47 AM
But why are there still monkeys? Like Luskin, I mean...
Posted by: raven
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October 15, 2009 10:50 AM
They are all transitional. And we never get tired of them.
For sure. One source I read claims that pterosaurs and pterodactyls were probably warm blooded and had a fur like covering.
Blame it on Noah and Yahweh. The Big Boat salvage operation was a near total failure and 99+% of the biosphere didn't make it. We miss our dinosaurs and flying reptiles.
Posted by: PZ Myers
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October 15, 2009 10:53 AM
Monkeys like Luskin have their own, unique place in the ecosystem. Who else would suck up all that scum?
Posted by: SQB (fuck death)
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October 15, 2009 10:55 AM
Fixed that for you.Posted by: Dave Hone
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October 15, 2009 10:56 AM
Sorry to be picky PZ but you have your pterosaurs a little mixed up. All pterosaurs are, well, pterosaurs, but that basal group that originate in the Triassic are the 'rhamphorhynchoids' (if you are happy with paraphyletic names) or if you prefer the non-pterodactyloid pterosaurs. Equally, the later clade should be the pterodactyloids snce pterodactyls in really more an Anglicisation of the genus name *Pterodactylus*.
However, all in all this is a great write up and I'm pleased to see pterosaurs getting the press they deserve. This really is a very cool animal and tells us much about both pterosaur evolution and, as you note, evolution in general.
On another note, there are actually three pterosaur embryos known, two from China and another from Argentina with two of these being diagnoable to family level at least and most researcher being happy that they can pin down the genera to which they belong. In addition to the very large numbers of specimens we have for some taxa that include young juveniles through to ig adults, we actually have a pretty good idea about pterosaur ontogeny, though admittedly mostly post-embryonic.
Good work!
Posted by: Sean
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October 15, 2009 10:58 AM
This would be a good opportunity to mention Mark Witton, the paleontologist and artist who painted the likeness of the creature. If you haven't read his writing and seen his paintings, then you are in for a treat.
Check it out here:
http://www.flickr.com/photos/markwitton/
Posted by: Gregory Greenwood
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October 15, 2009 10:58 AM
"I wish…having some pterosaur embryos would be exciting"
Think what you are saying PZ! Have you never watched Jurassic Park? You are going to kill us all with your mad scientist experiments. Recreating velociraptors (Ok, I know that they were in actual fact the size of turkeys, but I bet they were vicious little bastards) and a huge expendable extra-eating T-Rex just for kicks. Jeff Goldblums movie career is not worth the end of civilisation.
Hollywood teaches it, so it must be true . . . right?
Posted by: Sven DiMilo
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October 15, 2009 10:59 AM
So cool. All three Figs. going right into Monday's lectures.
Posted by: Ville Sinkkonen
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October 15, 2009 10:59 AM
corrections:
The two main groups are Rhamphorhynchoids and Pterodactyloids not Pterosaurs and Pterodactyls.
Pterosaurs or pterosauria is the name for the whole group and pterodactyl is just popular term for Pterosaurs.
Posted by: Dave Hone
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October 15, 2009 11:02 AM
@Raven - the evidence for warmbloodedness (or homeothermy as many prefer) in pterosaurs is circumstantial. As for the fur-ike covering there are indeed a number of specimens preserved with 'pycnofibers' as they were recently named (see here: http://archosaurmusings.wordpress.com/2009/08/05/what-on-earth-are-pycnofibers/). At least six specimens across a range of taxa preserve them and there were quite likely present on all pterosaurs.
Posted by: David Marjanović
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October 15, 2009 11:03 AM
HAAAAAAARRRRRGH!
I have enough. I registered on the spot, during worktime. (I hope I didn't inadvertently create a blog in doing so.)
PZ… what in R'lyeh makes you think that 1) anyone other than the cretinists and the French has used the term "pterodactyl" in the last 100 years, and 2) "pterodactyls" are not pterosaurs???
Here goes:
– Pterosauria is the term for the entire clade.
– A subclade within this is Pterodactyloidea (in blue in the figure with the tree).
– Those pterosaurs that are not pterodactyloids (in red in the figure) used to be grouped under "Rhamphorhynchoidea", but this assemblage is paraphyletic, so the term isn't used much anymore.
The paper gets all of this right, and that includes the figure captions you copied.
– When "pterodactyl" was still in general use as an informal term (think The Lost World by Sir Arthur Conan Doyle), it designated all pterosaurs.
Darwinopterus goes a long way to closing the gaps in our understanding of the origin of Pterodactyloidea; that's what makes it so significant.
BTW, I'm not sure about the Middle Jurassic age; Anchiornis is from the same site, AFAIK, and was said to date from the beginning of the Late Jurassic. But (even though it's frankly hard to believe) we don't have access to Proc. R. Soc. B here in the National Natural History Museum of France, so I haven't read the paper yet.
Posted by: Rev. BigDumbChimp
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October 15, 2009 11:07 AM
Luskin ins't a monkey he's a semi-trained attack mouse.
squeeeek.
Posted by: David Marjanović
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October 15, 2009 11:09 AM
Fuck. So I did create a blog with a deeply, deeply silly address.
Typepad/Typekey crash 2/3 of the time, Movable Type (despite being native) crashes 2/3 of the time, OpenID screws the name up, Vox creates a blog… have I got any options left?
PZ, are you sure you can't switch registration off again?
Come on. Where would a bradymetabolic pterosaur get the endurance to… like… fly, and why would it have thermal insulation which actively impedes ectothermy?
Posted by: Rev. BigDumbChimp
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October 15, 2009 11:10 AM
ins't?
what the hell is ins't?
Posted by: Gregory Greenwood
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October 15, 2009 11:12 AM
I was idly googling when I had a revelation.
I think I was just saved by Raptor Jesus!
(I have just failed a tech-skills check on 3d6 for linking, so you will just have to google it.)
Posted by: Glen Davidson
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October 15, 2009 11:13 AM
But see, you can do intelligent design science with it. Just figure out what the designer (ok, baby Jesus) was thinking.
Which was, oh, um, well, "let's design this like evolution would."
I mean, you literally could turn ID into a science. Just as long as the Designer thinks according to genetic algorithms.
Glen D
http://tinyurl.com/mxaa3p
Posted by: Dave Hone
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October 15, 2009 11:16 AM
"Come on. Where would a bradymetabolic pterosaur get the endurance to… like… fly, and why would it have thermal insulation which actively impedes ectothermy?"
David, I said the evidence was circumstantial. I didn't say the evidence was unconvincing or that it was likely that they were ectotherms. I think they likely were endothermic, but I also think it incorrect to say the 'definitely were' or that the evidence is either 'overwhelming or incontrovertible'.
Posted by: Gregory Greenwood
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October 15, 2009 11:16 AM
"ins't?
what the hell is ins't?"
Congratulations, Rev. BDC. You have just invented a new word.
"Luskin ins't a monkey he's a semi-trained attack mouse.
squeeeek."
We should get in that gnome mouse hunter from Terry Pratchet's Discworld novels.
Posted by: octopod
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October 15, 2009 11:19 AM
I agree with David Marjanovic@#14, PZ. Cladistics FAIL.
Posted by: David Marjanović
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October 15, 2009 11:23 AM
Why cladistics? Cladistics has nothing to do with it. Nomenclature fail.
Posted by: kopd
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October 15, 2009 11:26 AM
Who knew that the whole pterosaur/pterodactyl thing would ruffle so many feathers? Apparently my understanding of the topic is 100 years behind as I thought there were pterosaurs and pterodactyls (and a couple others). Apparently that makes me a cretinist or French. Well, I will just tip my béret to you as I finish my mocha. Au revoir.
Posted by: Pygmy Loris
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October 15, 2009 11:29 AM
Sorry PZ, but I'm going to have to agree with David and octopod. Massive nomenclature and cladistics fail.
Posted by: SteveF
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October 15, 2009 11:37 AM
Could one of the more palaeo orientated people explain something for me please, the idea of modularity and mosaic isn't something I'm too familiar with. The authors write:
These contrasting results emphasize two key aspects of Darwinopterus: the complete absence of ‘intermediate’ character states that fall between those states found either in basal pterosaurs or in pterodactyloids (figure 3), and the almost perfect modularity exhibited by the mosaic pattern of character state distributions found in this pterosaur.
I'd actually only really heard modular and mosaic as applied to fossils coming from YECS. In his discussion of Tiktaalik, Sarfati writes:
Many of the alleged transitional forms do not have structures in transition from one form to another. Rather, the alleged transitional nature is a combination of fully-formed structures that in themselves are not transitional.9
For example, Archaeopteryx has fully formed flight feathers, an avian lung and an avian braincase (which is why the ‘hoax’ claim is indefensible), but had allegedly reptile features like a tail and teeth. Alleged whale evolution also has a number of ‘modules’, as documented in Walking whales, nested hierarchies, and chimeras: do they exist? These creatures with a mixture of characteristics are called mosaics or chimeras.
http://creation.com/tiktaalik-roseae...y-missing-link
the main link being to this attack on whale evolution:
http://creation.com/article/1551
Posted by: PZ Myers
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October 15, 2009 11:43 AM
Sorry, gang, it's the distinction the authors make. I should have been more clear and drawn the line between basal pterosaurs and pterodactyloids, though.
Posted by: howdy-lentils
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October 15, 2009 11:44 AM
When I was a kid Rhamphorhynchus was my favorite of all, mainly because of the funky tail and the fact that as a third grader, I could spell and pronounce "Rhamphorhynchus."
Posted by: mythusmage
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October 15, 2009 12:23 PM
As a transitional animal Darwinopterus was a piker because it only bridged families. Myxozoa bridge kingdoms. Beat That for a transitional life form.
Posted by: Jason A.
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October 15, 2009 12:26 PM
PZ:
An honest-to-goodness crocoduck?
Posted by: Aratina Cage
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October 15, 2009 12:34 PM
Jason A., I think you have it backwards. It's a duckodile.
Posted by: Peter Ashby
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October 15, 2009 12:34 PM
@SteveF
Modularity in embryonic development is a big idea at the moment as well, which would be the mechanism by which you get mosaic features in evolution. The two concepts (Paleontology and Development) are not entirely congruent but the idea is mechanistically plausible. It's partly because genetic clusters of genes that operate in the same time/place are common and include the genes that control the whole thing. If you tweak or add a new control sequence for one of these regulatory genes you affect all the others as a unit.
How 'easy' it is for the 'right' variation to come up depends on how the control of the regulatory genes is put together (a constraint on evolutionary freedom of movement). Some genes have separate regulatory sequences for different times/places (mouse Myf5 is one such) but others have different methods. There is more than one way to get a gene to turn on in different times/places/tissues. Some of them are downright weird, like iirc myosin light chain kinase. There is a transgene of part of the control sequences for it and it is graded down the body axis, however the native gene is not so graded, other sequences then smooth out the gradient to produce the final pattern. One doozy of a constraint there.
Posted by: Ray Moscow
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October 15, 2009 12:35 PM
If pterodactyloids came from basal pterosaurs, then why are there still basal pterosaurs? Answer me that, Mr. Evolutionist!
I was in Lyme Regis, near where Mary Anning found a Dimorphodon specimen, last weekend but didn't find any pterosaurs -- yet! I did get a trace ammonite and a few other bits, though. (Turns out that I need to be looking a bit further east along the coast.)
Since one can buy ammonite fossils for about £2 in any of the local shops, I'm probably inordinately proud of finding what I did.
Posted by: The Science Pundit
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October 15, 2009 12:40 PM
Aha! So transitional fossils would look like crocoducks!!
ps---I now see that Jason A (#30) beat me to the joke. :-(
Posted by: a_ray_in_dilbert_space
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October 15, 2009 12:43 PM
Ah, but PZ, every time you find a transitional fossil, you turn a gap into two gaps (OK, two much smaller gaps). That makes twice as much evidence against evolution and twice as many gaps for a deity to hide in. Bwaaahaaaahaaaaa!
Posted by: Andreas Johansson
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October 15, 2009 12:47 PM
You lucky nondyslectic bastard! As a kid I for quite some time believed that pterosaurs were named for someone called "Peter" ...Posted by: David Marjanović
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October 15, 2009 12:55 PM
It does make you as uninformed as a cretinist. BTW, nobody outside the army wears a béret anymore, at least not here in Paris.
The basal pterosaurs are those pterosaurs which are close to the base (root) of the tree. Not all pterosaurs are (equally) basal. :-|
They don't really bridge anything. They are good old Real True Amoebae (Amoebozoa) which evolved partial multicellularity independently from everyone else.
Posted by: Knockgoats
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October 15, 2009 1:47 PM
David,
Your link doesn't seem to mention Amoebozoa, and tentatively classifies the Myxozoa within Metazoa.
Posted by: amphiox
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October 15, 2009 2:15 PM
"We should get in that gnome mouse hunter from Terry Pratchet's Discworld novels."
In other words,
SQUEEK.
Posted by: David Marjanović
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October 15, 2009 2:56 PM
Oh, stupid me. My link does mention Amoebozoa (at a node in the tree), but Myxozoa is Myxosporea = Cnidosporida, a clade of about tetracellular cnidarian parasites, the sister-group of the fascinating diploblastic worm Buddenbrockia. I knew something was fishy about the name… I confused them with the Mycetozoa, the slime molds.
Interestingly, however, this happens not to change my point: even the real myxozoans don't "bridge kingdoms". :^) They're simply animals.
Posted by: teachingsapiens.wordpress.com
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October 15, 2009 3:40 PM
Hey, you mixed up the... Oh.
Is it a croco... Um...
Nevermind.
I used this paper to open lecture today and my majors found it to very interesting and quite exciting to see hot off the inter-presses research. Thanks!
Robert B / @RobsterFCD
PS. I'd just like to use this to point out that when one of us makes a mistake, even if that one happens to be PZ, we are merciless in our pointing it out.
Posted by: Sven DiMilo
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October 15, 2009 5:16 PM
Yeah, they're degenerate jellyfish, as noted above. No bridging to see here.
Perhaps Mr. Kellogg ("mythusmage") also made the mistake DM did--slimemolds seem to "bridge kingdoms" better than myxozoans. But of course they don't really--just another independent (and incipient?) evolution of multicellularity.
Posted by: kopd
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October 15, 2009 5:20 PM
BTW, nobody outside the army wears a béret anymore
You don't watch Mythbusters.
Posted by: kopd
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October 15, 2009 5:26 PM
Okay, the Mythbusters aren't French. But berets are such a fun cliche. I just can't let go of my fun mental image of somebody sitting under the Eiffel Tower, wearing a beret, sipping a latte and discussing pterodactyls. :-D
In fact, that is now on my bucket list.
Posted by: David Marjanović
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October 15, 2009 6:47 PM
Insects cheat by being tachyaerobic in spite of being bradymetabolic. This is made possible by the trachea system that vertebrates lack. Bumblebees are also part-time homeotherms and part-time endotherms... a bit like hummingbirds with their nighttime torpor, at least superficially.
Posted by: David Marjanović
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October 15, 2009 6:49 PM
Commenting has become pretty slow again, BTW.
Posted by: Silič O'Nopolitanopoulos, Färschdbischuf Beesknees aus Ulm und Klein Elguth, Elector Pharynguline.
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October 15, 2009 7:16 PM
Thank you, PeeZed, for composing such a subtle and intricate trap to lure out David.
Why now has a blog that I'll expect him to fill with lossa Marjanovocal goodness.
Excellent!
Posted by: Kel, The Privileged View From Nowhere
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October 15, 2009 7:48 PM
Stop it, you're ruining X Lurker's echo chamber hypothesis!Posted by: Sven DiMilo
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October 15, 2009 8:03 PM
My point, of course, is that we don't really know whether pterosaurs were capable of similar "cheating."
That's a conclusion from correlation alone, and you should be careful about stating such guesses about mechanism as fact (unless you know of experimental data that bear on the subject; I do not).
Yes, I know all about temporal heterothermy. And pterosaurs? Statements about their physiology are highly conjectural in every case.
Posted by: Jadehawk, OM
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October 15, 2009 8:27 PM
stop using words google can't explain! :-pPosted by: Sven DiMilo
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October 15, 2009 8:31 PM
Jadehawk, even most physiologists wouldn't know that one. It's a jargonous coinage of the paleophys types meaning "able to support relatively high levels of aerobically supported exercise."
Similarly, "bradymetabolic" means "having a relatively low resting metabolic rate."
Posted by: Jadehawk, OM
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October 15, 2009 8:34 PM
thanks, that helps immensely.
Posted by: 01jack
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October 15, 2009 8:44 PM
When I was a kid Rhamphorhynchus was my favorite of all, mainly because of the funky tail and the fact that as a third grader, I could spell and pronounce "Rhamphorhynchus."
And I could say, spell, and draw a really cool Rhamphorhynchus. I remember the hour I spent in third grade teaching myself all three while the rest of the class was doing whatever.
Posted by: mythusmage
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October 16, 2009 2:30 AM
David, #40
But, myxozoa also reproduce via spores, a slime mold trait. Indeed, one might classify animals as multicellular motile organisms that reproduced via gametes, or which produce gametes is in the case of placozoa.
Because of their resemblance to the jellyfish they are said to be degenerate examples of such, but I have to wonder if the spore production indicates better an ancestral condition, one that was turned to another purpose with the evolution of gametes. This would make the myxozoa near animals and not true animals themselves.
My main point is, true gaps are rare. An animal such as Homo habilis more bridges the gap between Australopithecus and Homo than it marks gaps between a preceding Australopithecus species and a succeeding species of Homo. Bridges it because it is largely an Australopithecine species with a few notable Homo traits.
You also illustrate the perils of data interpretation, for we tend to see things as we think they should be. A possibility we are not aware of is a possibility we cannot consider
Posted by: mythusmage
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October 16, 2009 2:41 AM
Sven, #42
We see myxozoa as degenerate jellyfish. Now I understand that lost traits can be re-expressed in descendants of animals that originally lost them, but usually this re-expression serves a purpose. As I understand it, the evolution of gametes proved to be a more effective method of reproduction than spores, and so with the appearance of gametes the ability the produce spores was lost, and the mechanism for injecting spores into a victim was repurposed to injecting poison.
In so far as myxozoans reproduce via spores that are injected using the same mechanism cnidarians use to inject poison, and do not produce gametes, I have to wonder about the degenerate jellyfish interpretation.
Posted by: windy
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October 16, 2009 4:05 AM
My main point is, true gaps are rare.
Err... what is a "true gap"?
Posted by: Josh
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October 16, 2009 5:53 AM
What does this mean?
Posted by: mythusmage
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October 16, 2009 6:08 PM
Windy and Josh,
Sorry, but I don't have any academic or legal training, when I use a word I use it according to be most commonly used meaning. If you're too well educated to understand what the most commonly used meaning of "gap" is, may I suggest a long talk with your professors regarding their life-long confusion of ideation with reality.
Posted by: Nerd of Redhead, OM
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October 16, 2009 6:18 PM
Mythusmage, Windy (I think) and Josh are professors...
Posted by: David Marjanović, OM | October 17, 2009 8:19 AM
Free access to the paper and the supplementary information!!!
The first link goes straight to the pdf, the second to a page where you can download the Word file that is the supp. inf.; you should read what it has to say about the age (might be Late just as well as Middle Jurassic).
========================================
Sili, I do not have a blog. What you're looking at (and you've misread the stupid address) is an automatic byproduct of registration. I don't have time for blogging.
I'm using phylogenetic bracketing here. Have you got something better to offer?
"Spore" is a very, very, very general term that designates a lot of very different things. The spores of Bacillus, ferns, amoebae, and cnidosporidians have nothing in common with each other that isn't shared by, say, rotifer eggs.
No, no, no. Don't confuse definition and diagnosis. Animalia is a clade; it consists of one ancestor and all its descendants.
The main argument is molecular.
Er...
If the fossil record were complete, gaps in the tree wouldn't exist at all. If we restrict ourselves to the living, gaps are all over the place. Nature, or at least death, does not abhor a vacuum.
That didn't happen here.
<facepalm>
You contrast "reproduction by gametes" with "reproduction by spores"?!?
Man. You have a lot to learn about eukaryote reproduction in general: plants, ciliates, dinoflagellates, foraminifera, choanoflagellates, yeast, everything.
Did you really not know that plants have gametes? Is that not taught in highschool where you come from?
You misunderstand. The question was about the meaning of "true gap".
You illustrate the perils of talking about things one knows way too little about.
Really, take a little break from your myths and magic, and sit down and read about the wondrous diversity of life.
========================================
BTW...
PZ, you still haven't fixed your use of "pterosaur" and "pterodactyl". Pterodactyloids are pterosaurs.
Posted by: Sven DiMilo
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October 22, 2009 7:57 PM
? I don't think you are, at least as I understand the term. All insects (plus myriapods and some arachnids) have tracheal systems, but only a few insects are capable of temporal heterothermy and consequent huge aerobic scopes. What are you bracketing with what to conclude a causal relationship?
But yes, "spore" is a very general term for a dormant dispersal stage, and fungal, plant, and animal "spores" are not homologous.
Posted by: JackSpratt
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March 19, 2010 3:19 PM
I see a a crack that runs across where the head attaches to the spine. Would it not be more parsimonious to say that they have mixed the head of one creature with the body of a different creature?
Posted by: Sven DiMilo
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March 19, 2010 3:26 PM
Good eye, there, Jack. It's amazing that none of those eggheads figured that one out, eh?
Posted by: stevieinthecity#9dac9
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March 19, 2010 3:27 PM
I see a crack in your logic.
Posted by: Brownian, Most Vicious & Petty of Pharyngulites
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March 19, 2010 3:49 PM
Don't be foolish, Jack. That's no mix-up. That there is clearly a panda, its skeleton bent and distorted via the intricate processes of of Flood Geology (which I and every other person on earth am at a loss to describe in any meaningful detail, so instead I'll just link to a picture of what we think the ark looked like.)
Posted by: JackSpratt
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March 19, 2010 4:01 PM
Are there other pictures of this creature that could settle this question?
I have not been able to find any.
Posted by: stevieinthecity#9dac9
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March 19, 2010 4:11 PM
Of this particular fossil or is there another fossil of the same animal?
I know where you're going, and where you've gone. But I'll play along.
Posted by: Nerd of Redhead, OM
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March 19, 2010 4:19 PM
I think maybe the real question is how many fossils do not not have at least one broken bone? After all, some shift can occur during the fossilization process. Although, this is beautiful fossil in one layer with the bones in approximately right postions. So the parsimonious position would be that it is a real fossilized critter.Posted by: Jadehawk, cascadeuse féministe
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March 19, 2010 4:25 PM
Parsimony is Satan's bride.Posted by: Brownian, Most Vicious & Petty of Pharyngulites
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March 19, 2010 4:28 PM
Yes. Look at the bottom right hand corner. See (f). It doesn't appear that you looked very hard.Posted by: Celtic_Evolution
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March 19, 2010 4:43 PM
In other words, JackSpratt, just looking closely at the picture from this post should have made you realize that there were two different fossil specimens being shown. (a) and (b) are different than (f).
Posted by: JackSpratt
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March 19, 2010 7:39 PM
I meant pictures of Darwinopterus modularis other than those shown here.
Posted by: Nerd of Redhead, OM
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March 19, 2010 7:42 PM
Link please.Posted by: Jadehawk, cascadeuse féministe
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March 19, 2010 7:54 PM
why? your absurd claim that they're fakes has already been laid to rest, since there's two different individuals depicted, and only one of them has that crack that worries you so much.Posted by: David Marjanović
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March 19, 2010 8:56 PM
The crack runs through the spine, through a vertebra in fact, and continues through both wings. There's no way to get that mixed up – or even to fake it.
Follow the two links at the top of comment 60!
(Really, why did you comment on this thread without having read all of it first?)
Posted by: JackSpratt
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March 20, 2010 9:33 AM
It really doesn't matter to me much but these pictures do not support the idea that this is all one animal.
But there is no point in arguing it.
If anyone can point us to other pictures of other fossils that we can access for free please do so.
I have not seen any on google.
Posted by: Nerd of Redhead, OM
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March 20, 2010 9:41 AM
Ah, Mr. Sprat. Like we would take your word for anything without evidence. Which you fail to supply, and only give us your unsubstantiated opinion. Which is worthless. And given your lack of proper scientific training, probably less than worthless. So, time for you to quit arguing your inane point.
Posted by: JackSpratt
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March 20, 2010 9:51 AM
Ah, Mr. Nerd - can you point us to any other pictures of fossils of this animal? I am not interested in your unsubstantiated opinion.
Posted by: 'Tis Himself, OM
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March 20, 2010 10:04 AM
However you're more than willing to give your unsubstantiated opinion.
You've been told where there's another picture of D. modularis. But since that picture doesn't support your pretense that the fossil is a fake, you're ignoring it and demanding more information. We all know if you were given another picture and it didn't support your pretense, you'd dismiss it as well. Sorry to disturb your creationist delusions but that's a genuine fossil of a genuine pterosaur.
Now do you have anything substantial to offer or are you going to admit that your creationist bullshit is nothing but imaginary stupidity?
Posted by: Nerd of Redhead, OM
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March 20, 2010 10:05 AM
Mr. Sprat, until you can produce conclusive evidence for your inane claim, like being able to show by examining the fossil that the strata don't line up, or the dating of the layers don't match, all you have is hot air. So, go and look at the real fossil. If you have the proper credentials, you might even get to look at it up close. But, given your unscientific attitude to date, the chances of that happening are slim. You are wrong until you prove yourself right. And the scientists who wrote the paper have done their job at convincing fellow scientists they are right.
Posted by: JackSpratt
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March 20, 2010 10:18 AM
"Tis. I am not a creationist.
What is this other picture you refer to? Please just point to it (a link or something) rather than referring to it. I do not know the picture you are referring to.
Posted by: Nerd of Redhead, OM
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March 20, 2010 10:24 AM
Still no evidence from Sprat. Almost like he knows he has nothing but flatus.
Posted by: Sven DiMilo
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March 20, 2010 10:26 AM
Mr. Spratt is putting the rest of you "skeptics" to shame here. He has sniffed out and zeroed directly in on the flaw, obvious in hindsight, that escaped the notice of all of the people who have directly examined the fossil itself. And he has done so using only internet photographs! (hey wait...Jack, are you Dave Peters? only Marjanović wll get that one)
Can't you see he's merely asking for more evidence before making up his mind on whether to believe in this possibly fakable and therefore clearly faked "animal"? Remember Piltdown! (not the commenter) Remember Archaeoraptor!! Remember uh Nebraska Man! HOAX!!! HOAX I TELL YOU!!!!
keep on doubtin', Jack
Posted by: Nerd of Redhead, OM
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March 20, 2010 10:34 AM
Oh, and Mr. Sprat, the fossil will remain as scientific fact until more science, in the form of a paper showing it is a hoax, is published in the peer reviewed literature. What you say at this blog is not science, and doesn't effect science. If you choose not to accept this fossil as real, do yourself a favor and keep it to yourself while you collect the data to truly refute it.
Posted by: David Marjanović
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March 20, 2010 10:42 AM
Hello-o! I just di-id! In the comment directly above yours!!!
LOL. No, it's pretty clear he's not...
Posted by: 'Tis Himself, OM
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March 20, 2010 10:52 AM
Sorry about that. You were using the creationists' arguments so well I assumed you were one. My apologies for not recognizing the difference between you and other people using the same arguments. BTW, it's only a singlt apostrophe on 'Tis.
Look at post #60 on this very thread. You'll find links there.
Posted by: JackSpratt
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March 20, 2010 11:13 AM
The links on post #60 require a sign-in or payment.
All I can see is the abstract.
Posted by: Nerd of Redhead, OM
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March 20, 2010 11:20 AM
The supplemental material can be download for free.
Posted by: a_ray_in_dilbert_space, OM, A little FUCKING ray of sunshine
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March 20, 2010 11:34 AM
Jack Spratt,
What you are failing to take into account (one of many things, in fact) is that when assembling a fossil from fragments, the stone around the fossil also tells a story. If you look at sedimentary rock, it is clear that the strata are different from one layer to another. Size of particles, amount of cement (iron oxide in this case from the look), particle composition, compactness,...--they all have to match. In fact, you can even look at isotopic composition and it will vary throughout the different strata. This makes fakes easy to spot, and it assists experts in assembling the fossil.
You are basing your opinion on your own ignorance.
Posted by: David Marjanović
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March 20, 2010 12:04 PM
Oh, sorry, that's new. And while the supplementary information is still freely accessible, the three photos in it don't show the neck or the wings... However, they do show two different individuals.
Better yet: try to find pictures of Wukongopterus. It was described almost at the same time, by different people, and is probably the same thing...
Posted by: JackSpratt
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March 20, 2010 5:25 PM
If you think that this is a valid animal, then you have no defence against the points made in the article that SteveF referred to:
http://creation.com/walking-whales-nested-hierarchies-and-chimeras-do-they-exist
Posted by: John Morales
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March 20, 2010 5:53 PM
JackSpratt, no defense is needed against fatuity.
Posted by: JackSpratt
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March 20, 2010 5:59 PM
"As I mentioned at the beginning, this is an example of development and evolution in congruence. We do find modularity in developmental process — we have genetic circuits that are expressed in tissue- and region-specific ways in development. We can talk about patterns of gene expression that follow independent programs to build regions of the body, under the control of regional patterning genes like the Hox complex. In that sense, what we see in Darwinopterus is completely unsurprising."
Okay. But how does that work in the case of "convergent evolution". The animals are not related and yet still execute the same "independent programs"?
Posted by: John Morales
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March 20, 2010 6:14 PM
All metazoans are ancestrally related.
Posted by: Jadehawk, cascadeuse féministe
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March 20, 2010 6:17 PM
*snortle*Posted by: JackSpratt
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March 20, 2010 6:19 PM
John Morales.
Do you understand the idea of "convergent evolution"?
All metazoans being ancestrally related does not explain instances of "convergent evolution".
Posted by: Nerd of Redhead, OM
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March 20, 2010 6:28 PM
Evolution is sloppy. What works does get selected for, and selection is a very powerful force. And if selection works toward something as being the most selected, because it is the most efficient, shapes may overlap, be it flying (birds and bats) or swimming (sharks and dolphins). Scientists understand this concept. You are obviously not grounded in what evolution is or means. Try reading books by Dawkins (Greatest Show on Earth), Coyne (Why Evolution is True), or Shubin (Your Inner Fish) for basic evolution.Posted by: Jadehawk, cascadeuse féministe
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March 20, 2010 6:31 PM
Jack, do you understand "form follows function"? do you understand that shared genomes can cause similar mutations even in divergent species, as long as the relevant chunk of the genome remains similar?
convergent evolution also isn't usually about "the same"; it's about "similar enough".
Posted by: John Morales
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March 20, 2010 6:32 PM
JackSpratt:
Convergent evolution.
You did say they were not related, remember? ;)
And no, it does not fully explain it, of itself. To do that, one also needs to take into account that form follows function, and similar ecospaces will require similar functions for success in any given ecological niche.
Posted by: Rorschach
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March 20, 2010 6:37 PM
Same toolkit genes in all animals, plus similar ecological niches or conditions, selective pressures, a random mutation here and there, and you get development of analogous structures, what's your problem ?
Birds and bats have wings, their common ancestor didn't.
Similar things have happened all the time, look at marsupials and mammals.
Posted by: JackSpratt
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March 20, 2010 7:07 PM
"A random mutation here and there".
It would be interesting to see somebody provide evidence that "random mutations" could happen often enough and quickly enough to explain any change that has ever occurred.
Can you provide any evidence that includes the rate of random mutations and the number of occurrences in an actual example from real life?
Posted by: David Marjanović
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March 20, 2010 7:16 PM
<sigh> The boring pseudonymous Woodmorappe, preaching as usual about things he doesn't understand.
Those wheeled vehicles do in fact have a genealogical tree – it's just that it's all in the heads of their designers, without actual procreation involved.
Of fucking course no traits change consistently in a whale-like direction. The tree of life isn't a pole, it's a tree. It branches. Natural selection doesn't have any foresight, and mutation doesn't have any sight at all... what Woodmorappe is looking at is diversification, and one branch of this bush has survived.
Woodmorappe believed the theory of evolution would predict consistent changes in a whale-like direction. This alone means he doesn't understand what he's talking about. It means I don't even need to go on.
But I'll do anyway. I haven't even finished the above quote.
The modularity aspect is real, but Woodmorappe exaggerates it. For instance, while the skull of Darwinopterus/Wukongopterus is of a general pterodactyloid type, it isn't identical to that of any particular pterodactyloid. Its tooth arrangement, for instance, is unique altogether in its details. (If you want the pdf of the paper, find me in Google Scholar and drop me an e-mail.)
The last sentence is Woodmorappe's ignorance of convergence. Again, it's not a pole, it's a tree, and Woodmorappe hasn't understood that.
That's not a goat that figure is showing... it's an ibex.
What? Nobody is saying that (which is why the dishonest Woodmorappe doesn't cite anyone for it). If they're really related, to the extent that the presence of one of these traits requires the presence of all of them, then convergence in one automatically means convergence in all. And that happens.
And incorrect phylogenies absolutely do result when people don't use enough information (which can be caused by simply not enough information being available). One case of this is what my PhD thesis is on.
To be fair, that's because nobody has ever tried. Nobody has conducted, to the best of my knowledge, a phylogenetic analysis of Cephalopoda with a reasonably large sample of species. There are just a few small proof-of-concept analyses that don't help with this particular issue.
"More"?
Woodmorappe doesn't seem to have noticed that reconstructing the evolutionary tree is what classification is nowadays. He's repeating himself without noticing. He doesn't understand what he's talking about.
That's exactly why tree reconstruction can't be done by using a single character or three.
It's also why nobody does that anymore. Try 300 or 400 as a minimum.
<yawn> Not everyone is using the same definitions for "rare" and "transitional". It's a simple misunderstanding.
Calling Gish a scientist? That's rich. Gish makes assumptions and states them; he never tests them.
Woodmorappe still hasn't understood the difference between a tree and a pole, between a mother and an aunt. He then goes on to elaborate on this lack of understanding by again insisting there must be no convergence, as if there were only one environment which never changed erratically. It's tiring.
Nonsense from front to back. Woodmorappe hasn't even noticed that "hindlimb reduction" means "smaller hindlimbs compared to the forelimbs"; and it hasn't crossed his mind that it's advantageous to reduce and lose the unneeded hindlimbs – they cause drag, and they need to be built and maintained with resources that could be invested in other things like faster growth or reproduction. There's always natural selection for losing everything, except for those things on which there's even stronger natural selection for keeping them.
The opposite is the case: they are unanimous in never finding these two as sister-groups. What's going on is that Woodmorappe hasn't understood what "sister-group" means and is too stupid to ask.
The sister-group of X is the branch that is only one node away from X. So, the sister-group of Ambulocetus is the large group composed of Remingtonocetidae, Rodhocetidae, Protocetidae, Dorudontidae, Basilosauridae, Mysticeti, and Odontoceti (according to Woodmorappe's fig. 2). Both of these together – Ambulocetus and the large group – form the sister-group to Pakicetidae.
SHOCK HORROR!!!1! The once enormous gap between hippos and whales has shrunk to the much, much smaller gap between Pakicetidae and Ambulocetus! Someone call the waaaaaahmbulance already, and won't somebody please think of the children!!1!!!
Man, is Woodmorappe making himself ridiculous.
Over here on Pharyngula, every new discovery of a halfway spectacular fossil that counts as transitional (in the sense the media or creationists would have it) gets commented by "oh well, two new gaps in the fossil record". I just explained why.
Scientific, or creationists?
SHOCK HORROR!!!1! The once enormous gap between hippos and whales has shrunk to the much, much smaller gap between Rodhocetidae and Protocetidae! Someone call the waaaaaahmbulance already, and won't somebody please think of the children!!1!!!
Woodmorappe making himself ridiculous again.
(And then again by failing to understand that the fluke is part of a tail.)
Isn't it fascinating that we now have a stepwise pattern, where previously we could only say "all these traits must have evolved sometime in the ancestry of whales, probably not all at the same time, but we can't tell in which order"? Now we can delimit the evolution of bigger, flatter feet to the origin of the Ambulocetus-Remingtonocetidae-Rodhocetidae-Protocetidae-Dorudontidae-Basilosauridae-Mysticeti-Odontoceti group after it and the ancestors of Pakicetidae had split, and the evolution of the fluke to the origin of the Protocetidae-Dorudontidae-Basilosauridae-Mysticeti-Odontoceti group after it and the ancestors of Rodhocetidae had split, showing us that the former happened earlier than the latter, which also happens to make sense from a biomechanical point of view.
When Archaeopteryx was discovered in eighteen sixty fucking one, creationists immediately demanded to see the intermediates between it and modern birds on the one side and between it and "reptiles" on the other. Immediately someone commented* that, if those additional intermediates were found, the creationists would demand to see the intermediates between the intermediates, and so on ad nauseam. Of course, that's exactly what happened, and here we see it again with whales. It's pathetic.
* The actual quote & citation from the early 1860s is in the book The Hot-Blooded Dinosaurs by Adrian J. Desmond, 1975. I don't have it here, unfortunately.
Easy: vehicles don't reproduce, they don't inherit, and they don't mutate, except in people's heads.
Because that's what happened to happen later on, as far as the evidence says. :-| It wouldn't have been predictable when those animals actually lived, at least not in any detail.
Huh?
What sense does it make to cherry-pick them and leave the entire rest (see Woodmorappe's fig. 2, and Indohyus) out?
Evolution is a process. You can't see a process by looking at a single stage of it.
Woodmorappe should calm down and consider Indohyus and the extant Tragulidae (chevrotains).
Again, this is expected. The Earth is not a laboratory where the environment changes steadily without the slightest back-and-forth wobbling for twenty million years, and a tree is not a pole.
The principle of parsimony is not a belief. But I didn't actually expect Woodmorappe to know the uttermost basics of science theory. <sigh>
if you are stupid enough to believe that convergence never happens.
"Astonishing"? Woodmorappe's knowledge of evolution is at the dinosaur-book-for-six-year-olds level.
Who cares about "all"? We expect most of these features to be present in at least some other mammals that hear underwater. What's important is that they're absent in the closest relatives of the whales.
Only creationists have such a point of view anymore. There is no progress. There's only natural selection for better adaptation to the current environment; what the current environment is changes all the time.
Again, this had to be expected from the way evolution works outside simplistic laboratory settings and creationist minds.
For crying out loud! The crown group of X is, by definition, the last common ancestor of all living members of X, plus all descendants of that ancestor! It doesn't mean "pinnacle of creation" or any other such metaphysical mumbo-jumbo!
To pick one blatant example of a reversal, the crown-group whales have lost the contact between the sacral vertebrae and the (much reduced) pelvis. This is a reversal to a state last seen in their ancestors 300 million years earlier. It also makes sense, because a strong connection to useless reduced hindlimbs simply isn't needed.
Woodmorappe seems to think it's an all-or-nothing issue: either ontogeny recapitulates phylogeny in every single detail, or it has nothing at all to do with evolution whatsofuckingever.
He's wrong.
Ontogeny evolves. That's why we can't simply watch it and pretend we're watching a rerun of evolution (and Haeckel was wrong about this, though even he wasn't that extreme actually); but it also means that shared derived characters in development can be used as data for reconstructing family trees, the same way data from adult morphology or from DNA can. Like the other two sources of data, development is subject to convergence, reversal, and so on, but, again like the other two, it's not random noise either; it contains phylogenetic signal.
A typical extinct land-dwelling artiodactyl with a rather crocodile-like head...
For the rest of the body (other than the head), see Indohyus and the chevrotains. For the head, have a loot at the entelodonts and the mesonychians for comparison.
That's a gross oversimplification (there are whale features all over the body). Woodmorappe pretends it's not. Well, probably he doesn't even know what an oversimplification it is.
Insert the "shock horror" paragraph again.
Fascinating how Woodmorappe completely fails to mention the simplest explanation – that mesonychians and whales are not sister-groups, but that mesonychians and artiodactyls are instead, while the whales are artiodactyls.
Further fascinating how he fails to cite the papers that have found just this simplest explanation in their analyses.
Shared derived character state.
One more case of Woodmorappe believing he knows what he's talking about when he doesn't. It's about time I cite the Dunning-Kruger effect.
More parsimonious? To conjure a being with magical powers out of thin air? When we don't need it to explain anything? More parsimonious?
Surprisingly, this part is actually correct (even though it's a bit exaggerated*). Many of those tooth characters are correlated with each other, so counting them separately amounts to counting a single character several times. Development genetics (PZ's field) has started to give us some insight into this.
* Most importantly, the "too detailed" part is a probability argument, not a claim of absolutes.
Wake me up when Woodmorappe shows me the skeletons of his ancestors unto the seven hundredth generation.
What do these people imagine the fossil record is like?
It does indeed depend on the definition of "whale".
If "whale" is defined as "everything more closely related to today's whales than to the hippos", then the pakicetids are whales. ("Closely related" is short for "sharing more recent common ancestors with".) That's the definition paleontologists are using these days.
Not to the point that we'd get phylogenetic grass in our analyses instead of a phylogenetic tree.
Such assertions were fashionable till the 1960s or so, when people had strange ideas about how evolution worked because they didn't know what we know today about genetics, fossils, and so on. Today, nobody outside of Russia makes such assertions anymore; what we're making are arguments from parsimony – from science – about which hypotheses we should prefer.
This is plain wrong. Why aren't there insect-headed vertebrates? Or insect-winged primates (Disney fairies)?
Throwing out the bathroom and the entire family with the bathwater.
Any more questions?
Posted by: 朴競花/박경화 (Gyeong Hwa)
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March 20, 2010 7:24 PM
Infectious bacterias are one. If you go back in the archives a couple of months, you'll see the rate of random mutations that we all face.
Posted by: David Marjanović
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March 20, 2010 7:27 PM
<wince> You probably mean marsupial mammals and placental mammals.
I've seen the evolution of resistance to a virus in a petri dish full of Escherichia coli, overnight...
Define "often enough and quickly enough".
The total number of mutations per generation is 100 to 200 in humans; Google will tell you how this was determined.
For the rate of mutations that affect the shape of the organism, you'll have to turn to bacteria and viruses; such studies have been done, but aren't easy, so there aren't many of them. Still, Google should find some.
Especially read up on Lenski's experiment; that one isn't about shape, but about ecological niche, which is what shape mostly is about in animals.
Posted by: Jadehawk, cascadeuse féministe
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March 20, 2010 7:30 PM
really? you pathetic, dishonest troll, here: http://www.genetics.org/cgi/content/full/156/1/297that took 2 minutes to google.
Posted by: Rorschach
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March 20, 2010 7:32 PM
Yes, thanks...:-)
Posted by: John Morales
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March 20, 2010 8:08 PM
David, take a bow. Your SIWOTI is strong.
The fail at the concept of deep time.
And, just because it's one of the best-ever posts
hereanywhere on the Web, I refer to The proper reverence due those who have gone before.Posted by: Nerd of Redhead, OM
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March 20, 2010 8:21 PM
Look up Lenski (PNAS 2008 I believe) in Google Scholar. E-coli that could metabolize citrate, after 33,000 generations developed the ability to metabolize citrate and grow well. Required 3 mutations.Now, show us conclusive physical evidence for your imaginary creator/designer. Put up or shut up.
Posted by: 'Tis Himself, OM
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March 20, 2010 8:27 PM
JackSpratt #81
Spratt, when you used "Woodmorappe" (real name Jan Peczkis) as a source, then you made it obvious the above statement is a lie.
Posted by: David Marjanović
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March 20, 2010 8:55 PM
Wow. Free access! :-9
That's the paper that determined the mutation rate in humans. Do read it, Jack.