Intelligent Design isn’t intelligent

[pitabread]

but you are the one who talked about phylogenetic trees. not me.

That's what the hierarchies related to living things are called: Phylogenetic tree - Wikipedia

 

[xianghua]

That's what the hierarchies related to living things are called: Phylogenetic tree - Wikipedia

so tell me what is wrong with this tree:

 

[pitabread]

so tell me what is wrong with this tree:

View attachment 253830

Can I ask you a personal question? Do you have a legitimate memory issue or learning disability?

I'm not trying to make fun, but considering how many times we've had the same conversations over and over, it makes me wonder why that is the case.

 

[The Barbarian]

good for him. i think otherhwise and proved it with designed objects.

Nope. So far, you've failed to show that anybiological entity is "designed."

 

[The Barbarian]

so tell me what is wrong with this tree:

The lack of homologies shows a lack of common descent.

 

[BradB]

An ignorant question, BradB, because you can easily find such examples, e.g. the evolution of blood clotting which is definitely beneficial!
See An Index to Creationist Claims
29+ Evidences for Macroevolution The Scientific Case for Common Descent is still valid.

So are you going to link me to a lab study on some multi celled organisms that was "known" to not have blood clotting genes anywhere in the population and it was observed developing? Or do we again have to take your word for it?

 

[BradB]

An ignorant question, BradB, because there are many "finely graduated chain of fossils leading between any two major forms". Evolution of the horse. Evolution of the wale. Evolution on Homo Sapiens, etc. etc.

People ignorant about fossils tend to demand ever more "finely graduated chains" but fossilization is rare and we have not discovered them all. Rationally, there will be gaps between fossils.
See An Index to Creationist Claims
29+ Evidences for Macroevolution The Scientific Case for Common Descent is still valid.

I see so then are you going to link me to finely graduated chain where a horse became or came from some other form, or where wales came from or became some other major form? Or do we just have to take your word for it?

 

[BradB]

And when you got them, you pretended you didn't see them. We all get it.



Your fellow YE creationist gave you a large number of them, and you pretended you never saw it. He admitted that it was "very good evidence for macroevolutionary theory." No point in denying it.

You're not the first to try that dodge.



The real demonstration came about when genetics showed that DNA relationships between major groups would give the same family tree as the one discovered by Linnaeus, who didn't even know about evolution. And we know it works, because we can test it on organisms of known descent.



Your fellow YE creationist showed you that they present "very good evidence for macroevolutionary theory." Since you're denying it, I'll put it up again for you:

Evidences for Darwin’s second expectation - of stratomorphic intermediate species - include such species as Baragwanathia27 (between rhyniophytes and lycopods), Pikaia28 (between echinoderms and chordates), Purgatorius29 (between the tree shrews and the primates), and Proconsul30 (between the non-hominoid primates and the hominoids). Darwin’s third expectation - of higher-taxon stratomorphic intermediates - has been confirmed by such examples as the mammal-like reptile groups31 between the reptiles and the mammals, and the phenacdontids32 between the horses and their presumed ancestors. Darwin’s fourth expectation - of stratomorphic series - has been confirmed by such examples as the early bird series,33 the tetrapod series,34,35 the whale series,36 the various mammal series of the Cenozoic37 (for example, the horse series, the camel series, the elephant series, the pig series, the titanothere series, etc.), the Cantius and Plesiadapus primate series,38 and the hominid series.39 Evidence for not just one but for all three of the species level and above types of stratomorphic intermediates expected by macroevolutionary theory is surely strong evidence for macroevolutionary theory. Creationists therefore need to accept this fact. It certainly CANNOT said that traditional creation theory expected (predicted) any of these fossil finds.
Kurt Wise, Toward a Creationist Understanding of Transitional Forms
https://creation.com/images/pdfs/tj/j09_2/j09_2_216-222.pdf



There are instances of both. Gould, for example, cites ammonites, forams, and horses as cases of gradual evolution.



Your denial of something posted just a few posts above feels to everyone else like maybe you're not being honest.

(Barbarian ask for a definition of information as it applies to populations, and an explanation of how to calculate it)

(declines to say)

This is why people are thinking you're dishonest. Be honest now; you don't really know what "information" means, and you can't even calculate how much any organism has, can you?



Of course we can. It comes from mutations. We can even measure how much information it adds to a population. Or rather, I can. You have no clue, do you? "Information" just sounded kind of technical and sciencey, and you thought you'd toss it in to impress us.

Bad idea.



Wrong again. Would you like me to show you the numbers?



Every new mutation increases information in a population.

Okay so I responded but for some reason my post disappeared. I will have to redo it here in a little while.

 

[pitabread]

So are you going to link me to a lab study on some multi celled organisms that was "known" to not have blood clotting genes anywhere in the population and it was observed developing?

You're not one those "if it didn't happen in a lab, it doesn't count" types are you?

Because the other 'out' you have if to then claim anything observed in a lab involved intelligent intervention and doesn't count either.

 

[BradB]

And when you got them, you pretended you didn't see them.

Whatever

Your fellow YE creationist gave you a large number of them, and you pretended you never saw it. He admitted that it was "very good evidence for macroevolutionary theory." No point in denying it.

First let me just say that I claim no one based on status or who they say they are. I accept their statements on a case by case basis only as it is shown to be true and supported. So the fact that Wise moves in creation circles has no relevance to me.

You're not the first to try that dodge.

Maybe we're just misunderstanding each other here. When I say "chain from one major form to another" maybe you don't understand that I mean from parent to offspring line not distant cousins right? Lets say for the sake of argument that we were going to show a dinosaur evolved into a bird. I would need progressive links from the long line of lineages leading from the dinosaur to the bird (with no sudden leaps) not a group of all birds and a tree hugging wombat said to be a distant cousin. If I understand your little cartoon drawings above correctly, your not saying here that the tetrapods are the direct line descendants of the Ray finned fish, but rather you think I wanted a chain of different major forms that are claimed to be related based on some small similar features? Sorry for the confusion.

The real demonstration came about when genetics showed that DNA relationships between major groups would give the same family tree as the one discovered by Linnaeus, who didn't even know about evolution. And we know it works, because we can test it on organisms of known descent.

I can see how you might think this to be logical. Except for a couple of problems. We are talking about Creation vs. Evolution. So in a discussion such as this we cant just come to the table "assuming" our opposition accepts our usage evolution as the basis for saying DNA similarity equates to relationship. To a creationist that is like saying that one of those household vacuum robots is related to a lawn mower bot simply because both use very similar computer coding. It may be that the creator wrote the code that makes a hand develop and function a certain way and the same code is used several times in any "product" in which a hand is part of the design. So yes we know DNA relationships work with known descendants because...ahem...they are known. We see humans have human babies all the time and we see monkeys have monkey babies all the time. We can test the DNA of a human and its baby and see similarity equates to relationship. But if we test a monkey DNA and a human DNA and see a similarity it is NOT logical to say that must mean relationship. Especially if one of the possibilities is they both have a common creator.

Wrong again. Would you like me to show you the numbers?

How about just a link to the paper showing the study that took place under laboratory conditions?

Every new mutation increases information in a population.

Oh really? So ever see a picture of a two headed snake? Did that mutation provide new gene increasing type of information that spawned a whole race of two headed snakes that had an advantage over their one headed snake relatives? Or did it actually die off rather quickly? When I say new gene increasing information I am talking about on a scale that took throughout the entire population and gave them an advantage over the previous population. How hard is this to understand? If we are trying to show all life has a common ancestor then that means for a frog to eventually turn into a handsome prince, a whole lot of gene increasing type of information had to have been added to the populations over time.

 

[pitabread]

gene increasing type of information

What do you specifically mean by "gene increasing type of information"?

When I say new gene increasing information I am talking about on a scale that took throughout the entire population and gave them an advantage over the previous population.

Are you talking about selective sweeps?

How hard is this to understand?

It comes down to use of terminology. "Gene increasing type of information" isn't a phrase you will find in a science textbook.

 

[The Barbarian]

So are you going to link me to a lab study on some multi celled organisms that was "known" to not have blood clotting genes anywhere in the population and it was observed developing? Or do we again have to take your word for it?

Yong Jiang and Russell F. Doolittle
PNAS June 24, 2003 100 (13) 7527-7532
The evolution of vertebrate blood coagulation as viewed from a comparison of puffer fish and sea squirt genomes
ABSTRACT:
The blood coagulation scheme for the puffer fish, Fugu rubripes, has been reconstructed on the basis of orthologs of genes for mammalian blood clotting factors being present in its genome. As expected, clotting follows the same fundamental pattern as has been observed in other vertebrates, even though genes for some clotting factors found in mammals are absent and some others are present in more than one gene copy. All told, 26 different proteins involved in clotting or fibrinolysis were searched against the puffer fish genome. Of these, orthologs were found for 21. Genes for the ``contact system'' factors (factor XI, factor XII, and prekallikrein) could not be identified. On the other hand, two genes were found for factor IX and four for factor VII. It was evident that not all four factor VII genes are functional, essential active-site residues having been replaced in two of them. A search of the genome of a urochordate, the sea squirt, Ciona intestinalis, did not turn up any genuine orthologs for these 26 factors, although paralogs and/or constituent domains were evident for virtually all of them.

Any argument against these evolving over time, would have to assume a huge number of independent events which produced a result that only looked like evolution. The likelihood of this would be 1/21!, or about 0.00000000000000000002.

 

[BradB]

This is not the real world, BradB.
Every animal that has ever existed has not become a fossil .

If you back read my posts you will see I don't expect a link from every generation. I only expect a slow steady transformation in a progressive way. If these don't or can never exist then all I'm saying is "stop claiming the fossil record proves universal common descent."

Thus there will be leaps. There is no "dinosaur suddenly in one step growing a huge sail". There is no "fish in one link suddenly having fully developed legs". If I am wrong, cite your scientific evidence.

I get presented with supposed chains with large leaps all the time friend. Here is just one such example in which I went through each link presented in that chain and showed the person the large leaps.

Reptile to mammal chain:

Limnoscelis- 299 to 251 mya. About 5 feet in length (Limnoscelis | fossil tetrapod genus) with legs splayed out in a sprawling pose.

Eothyris- Early Permian (299 mya). About a foot in length with unknown posture. (Eothyris - Wikipedia) Species is only known from a single skull.

Archaeothyris- lived 320 million years ago, in the late Carboniferous period. About 1.5 feet in length (Archaeothyris - Wikipedia) with legs splayed out in a sprawling pose.

Varanops- Late Permian (251 mya). Between 3 and 4 feet in length (Varanops - Wikipedia) with legs splayed out in a sprawling pose.

Haptodus- lived from Latest Carboniferous to Early Permian , (299mya). Was a "medium" sized (Haptodus - Wikipedia) predator with legs splayed out in a sprawling pose.

Dimetredon- lived between 280–265 million years ago. Almost 10 feet in length (Dimetrodon - Wikipedia) with legs splayed out in a sprawling pose. Most distinctive characteristic was the spectacular sail on its back. (pic 2)

Biarmosuchus- lived around 255 mya during the late Permian period. About 4 feet long (Biarmosuchus - Wikipedia) with legs underneath in an upright pose. No sail

Regisaurus- Only information found was that it was supposedly an extinct genus of Theriodont, (Regisaurus - Wikipedia) a bear sized animal that lived 265 mya. Regisaurus is depicted with legs underneath in an upright pose, and hair.

​

 

[BradB]

Yong Jiang and Russell F. Doolittle
PNAS June 24, 2003 100 (13) 7527-7532
The evolution of vertebrate blood coagulation as viewed from a comparison of puffer fish and sea squirt genomes
ABSTRACT:
The blood coagulation scheme for the puffer fish, Fugu rubripes, has been reconstructed on the basis of orthologs of genes for mammalian blood clotting factors being present in its genome. As expected, clotting follows the same fundamental pattern as has been observed in other vertebrates, even though genes for some clotting factors found in mammals are absent and some others are present in more than one gene copy. All told, 26 different proteins involved in clotting or fibrinolysis were searched against the puffer fish genome. Of these, orthologs were found for 21. Genes for the ``contact system'' factors (factor XI, factor XII, and prekallikrein) could not be identified. On the other hand, two genes were found for factor IX and four for factor VII. It was evident that not all four factor VII genes are functional, essential active-site residues having been replaced in two of them. A search of the genome of a urochordate, the sea squirt, Ciona intestinalis, did not turn up any genuine orthologs for these 26 factors, although paralogs and/or constituent domains were evident for virtually all of them.

Any argument against these evolving over time, would have to assume a huge number of independent events which produced a result that only looked like evolution. The likelihood of this would be 1/21!, or about 0.00000000000000000002.

Not a study observed under controlled lab conditions where gene was known not to exist in any of the population prior to study.

 

[pitabread]

Never mind.

 

[BradB]

You're not one those "if it didn't happen in a lab, it doesn't count" types are you?

Because the other 'out' you have if to then claim anything observed in a lab involved intelligent intervention and doesn't count either.

How else are we to make sure that it is not simply a case of already existing genes taking over in the population? Consider as an example when evolutionists once shouted that bedbugs evolved to be resistant to insecticide. The truth though is the protein that makes the bedbugs immune to insecticides already existed in a small minority of bedbugs and researchers merely injected that protein into a control group and then observed it become the dominant trait in that group. Scientists have known that mutations can make insects immune to the effects of insecticides for a long time. However, these are not as a result of a mutation which added new (never before existed) information.

A molecule of DDT acts by binding itself to a specific matching site on an insect’s nerve cell membrane, where it prevents the nerve from functioning properly. After enough DDT molecules are bound to the nerve cells, the nervous system breaks down and the insect dies. A mutation can occur in the insect’s DNA which makes the site that DDT attaches to, less specific (loss of information), preventing the DDT from binding to its intended site and rendering the insect immune to DDT. Of course changes in insect’s protein often render the insect less fit for its environment in some other way. After the insecticide threat is removed, the insect populations will usually switch right back to their original gene configuration. This is further evidence that this is not the kind of change that explains macro evolution.

The point I am making here is that without close monitoring and study of the change, how would you know if it was actual evidence of UCD type change or not?

 

[The Barbarian]

Barbarian, regarding information provided, but ignored:
And when you got them, you pretended you didn't see them.

Whatever

People notice. It doesn't do you much good.

First let me just say that I claim no one based on status or who they say they are. I accept their statements on a case by case basis only as it is shown to be true and supported. So the fact that Wise moves in creation circles has no relevance to me.

Wise is an honest YE creationist, who happens to be well-qualified to discuss the matter; he has a PhD in paleontology, and he is unwilling to lie about the evidence. He merely says he prefers his reading of the Bible instead. That's a respectable position.

Maybe we're just misunderstanding each other here. When I say "chain from one major form to another" maybe you don't understand that I mean from parent to offspring line not distant cousins right?

Yeah, we get that. It's an old attempt, but even most creationists have abandoned it. "If we don't have the fossil of every single individual in the series, it's not evidence."

Lets say for the sake of argument that we were going to show a dinosaur evolved into a bird. I would need progressive links from the long line of lineages leading from the dinosaur to the bird (with no sudden leaps) not a group of all birds and a tree hugging wombat said to be a distant cousin.

That's what Wise was telling you about, in the therapsid-to-mammal series. A long line of lineages progressively more and more mammal-like. The key difference is that mammals have one lower jaw bone and three bones in the middle ear, while reptiles have three bones in the lower jaw, and one in the middle ear:

Here's a few of the many transitional forms:

At one point, we have transitionals like Diarthrognathus, which has both reptilian and mammalian jaw joints.

I can see how you might think this to be logical. Except for a couple of problems. We are talking about Creation vs. Evolution. So in a discussion such as this we cant just come to the table "assuming" our opposition accepts our usage evolution as the basis for saying DNA similarity equates to relationship.

We know it works, because we can test it on organisms of known descent. So there's no question about that.

To a creationist that is like saying that one of those household vacuum robots is related to a lawn mower bot simply because both use very similar computer coding.

Yes, to a YE creationist, if he has no idea of genetics.

It may be that the creator wrote the code that makes a hand develop and function a certain way and the same code is used several times in any "product" in which a hand is part of the design.

That won't work for you, either. Because analogies like human and maniraptor "hands" are all constructed differently, even if they look very similar. On the other hand, dolphin fins, bat wings, horses feet and human hands all have the same bones. This makes sense only if mammals all evolved from a common ancestor. Homologies (same stuff, different uses), indicate common descent. Analogies (same uses, different stuff) do not.

So yes we know DNA relationships work with known descendants because...ahem...they are known.

Works with every other organism, too. And it works with related species, and related genera and related families, and so on. No point in denying it.

How about just a link to the paper showing the study that took place under laboratory conditions?

In 1982, Barry Hall of the University of Rochester began a series of experiments in which he deleted the bacterial gene for the enzyme beta-galactosidase. The loss of this gene makes it impossible for the bacteria to metabolize the sugar lactose. What happened next? Under appropriate selection conditions Hall found that the bacteria evolved not only the gene for a new beta-galactosidase enzyme (called the evolved beta-galactosidase gene, or ebg), but also a control sequence that switched the new gene on when glucose was present. Finally, a new chemical reaction evolved as well, producing allolactose, the chemical signal that normally switches on the lac permease gene, allowing lactose to flow into the cell.


In my book I quoted evolutionary biologist Douglas Futuyma's description of these experiments:


"Thus an entire system of lactose utilization had evolved, consisting of changes in enzyme structure enabling hydrolysis of the substrate; alteration of a regulatory gene so that the enzyme can be synthesized in response to the substrate; and the evolution of an enzyme reaction that induces the permease needed for the entry of the substrate. One could not wish for a batter demonstration of the neoDarwinian principle that mutation and natural selection in concert are the source of complex adaptations." [ DJ Futuyma , Evolution, ©1986, Sinauer Associates, Sunderland, MA. pp. 477-478.]
A True Acid Test

Oh really?

Yep.

So ever see a picture of a two headed snake?

Yep. Not a mutation.

When I say new gene increasing information I am talking about on a scale that took throughout the entire population and gave them an advantage over the previous population.

That's not what "information" means. If you make up new definitions for words, it's not surprising that you'll be confused a lot. How hard is this to understand?

If we are trying to show all life has a common ancestor then that means for a frog to eventually turn into a handsome prince,

This is the second problem YE creationists have in understanding biology; they often make up silly ideas and suppose scientists believe them.

a whole lot of gene increasing type of information had to have been added to the populations over time.

That's a testable claim. Show us how much information a frog has, and then how much information a human has, and tell us how much more the human has. Show your work.

 

[The Barbarian]

Not a study observed under controlled lab conditions

It was.

where gene was known not to exist in any of the population prior to study.

Doesn't matter. As you learned, any argument against these evolving over time, would have to assume a huge number of independent events which produced a result that only looked like evolution. The likelihood of this would be 1/21!, or about 0.00000000000000000002.

About 2 chances in a pentillion. Which is a trillion times billion. Pretty unlikely, um?

 

[The Barbarian]

If you back read my posts you will see I don't expect a link from every generation. I only expect a slow steady transformation in a progressive way. If these don't or can never exist then all I'm saying is "stop claiming the fossil record proves universal common descent."

As you know, your fellow YE creationist gave you a number of them. I showed you a few of the many reptile-to-mammal transitionals.

Here's a somewhat longer list:

• Paleothyris (early Pennsylvanian) -- An early captorhinomorph reptile, with no temporal fenestrae at all.
• Protoclepsydrops haplous (early Pennsylvanian) -- The earliest known synapsid reptile. Little temporal fenestra, with all surrounding bones intact. Fragmentary. Had amphibian-type vertebrae with tiny neural processes. (reptiles had only just separated from the amphibians)
• Clepsydrops (early Pennsylvanian) -- The second earliest known synapsid. These early, very primitive synapsids are a primitive group of pelycosaurs collectively called "ophiacodonts".
• Archaeothyris (early-mid Pennsylvanian) -- A slightly later ophiacodont. Small temporal fenestra, now with some reduced bones (supratemporal). Braincase still just loosely attached to skull. Slight hint of different tooth types. Still has some extremely primitive, amphibian/captorhinid features in the jaw, foot, and skull. Limbs, posture, etc. typically reptilian, though the ilium (major hip bone) was slightly enlarged.
• Varanops (early Permian) -- Temporal fenestra further enlarged. Braincase floor shows first mammalian tendencies & first signs of stronger attachment to rest of skull (occiput more strongly attached). Lower jaw shows first changes in jaw musculature (slight coronoid eminence). Body narrower, deeper: vertebral column more strongly constructed. Ilium further enlarged, lower-limb musculature starts to change (prominent fourth trochanter on femur). This animal was more mobile and active. Too late to be a true ancestor, and must be a "cousin".
• Haptodus (late Pennsylvanian) -- One of the first known sphenacodonts, showing the initiation of sphenacodont features while retaining many primitive features of the ophiacodonts. Occiput still more strongly attached to the braincase. Teeth become size-differentiated, with biggest teeth in canine region and fewer teeth overall. Stronger jaw muscles. Vertebrae parts & joints more mammalian. Neural spines on vertebrae longer. Hip strengthened by fusing to three sacral vertebrae instead of just two. Limbs very well developed.
• Dimetrodon, Sphenacodon or a similar sphenacodont (late Pennsylvanian to early Permian, 270 Ma) -- More advanced pelycosaurs, clearly closely related to the first therapsids (next). Dimetrodon is almost definitely a "cousin" and not a direct ancestor, but as it is known from very complete fossils, it's a good model for sphenacodont anatomy. Medium-sized fenestra. Teeth further differentiated, with small incisors, two huge deep- rooted upper canines on each side, followed by smaller cheek teeth, all replaced continuously. Fully reptilian jaw hinge. Lower jaw bone made of multiple bones & with first signs of a bony prong later involved in the eardrum, but there was no eardrum yet, so these reptiles could only hear ground-borne vibrations (they did have a reptilian middle ear). Vertebrae had still longer neural spines (spectacularly so in Dimetrodon, which had a sail), and longer transverse spines for stronger locomotion muscles.
• Biarmosuchia (late Permian) -- A therocephalian -- one of the earliest, most primitive therapsids. Several primitive, sphenacodontid features retained: jaw muscles inside the skull, platelike occiput, palatal teeth. New features: Temporal fenestra further enlarged, occupying virtually all of the cheek, with the supratemporal bone completely gone. Occipital plate slanted slightly backwards rather than forwards as in pelycosaurs, and attached still more strongly to the braincase. Upper jaw bone (maxillary) expanded to separate lacrymal from nasal bones, intermediate between early reptiles and later mammals. Still no secondary palate, but the vomer bones of the palate developed a backward extension below the palatine bones. This is the first step toward a secondary palate, and with exactly the same pattern seen in cynodonts. Canine teeth larger, dominating the dentition. Variable tooth replacement: some therocephalians (e.g Scylacosaurus) had just one canine, like mammals, and stopped replacing the canine after reaching adult size. Jaw hinge more mammalian in position and shape, jaw musculature stronger (especially the mammalian jaw muscle). The amphibian-like hinged upper jaw finally became immovable. Vertebrae still sphenacodontid-like. Radical alteration in the method of locomotion, with a much more mobile forelimb, more upright hindlimb, & more mammalian femur & pelvis. Primitive sphenacodontid humerus. The toes were approaching equal length, as in mammals, with #toe bones varying from reptilian to mammalian. The neck & tail vertebrae became distinctly different from trunk vertebrae. Probably had an eardrum in the lower jaw, by the jaw hinge.
• Procynosuchus (latest Permian) -- The first known cynodont -- a famous group of very mammal-like therapsid reptiles, sometimes considered to be the first mammals. Probably arose from the therocephalians, judging from the distinctive secondary palate and numerous other skull characters. Enormous temporal fossae for very strong jaw muscles, formed by just one of the reptilian jaw muscles, which has now become the mammalian masseter. The large fossae is now bounded only by the thin zygomatic arch (cheekbone to you & me). Secondary palate now composed mainly of palatine bones (mammalian), rather than vomers and maxilla as in older forms; it's still only a partial bony palate (completed in life with soft tissue). Lower incisor teeth was reduced to four (per side), instead of the previous six (early mammals had three). Dentary now is 3/4 of lower jaw; the other bones are now a small complex near the jaw hinge. Jaw hinge still reptilian. Vertebral column starts to look mammalian: first two vertebrae modified for head movements, and lumbar vertebrae start to lose ribs, the first sign of functional division into thoracic and lumbar regions. Scapula beginning to change shape. Further enlargement of the ilium and reduction of the pubis in the hip. A diaphragm may have been present.
• Dvinia [also "Permocynodon"] (latest Permian) -- Another early cynodont. First signs of teeth that are more than simple stabbing points -- cheek teeth develop a tiny cusp. The temporal fenestra increased still further. Various changes in the floor of the braincase; enlarged brain. The dentary bone was now the major bone of the lower jaw. The other jaw bones that had been present in early reptiles were reduced to a complex of smaller bones near the jaw hinge. Single occipital condyle splitting into two surfaces. The postcranial skeleton of Dvinia is virtually unknown and it is not therefore certain whether the typical features found at the next level had already evolved by this one. Metabolic rate was probably increased, at least approaching homeothermy.

To be continued...

 

[The Barbarian]

continued:

• Thrinaxodon (early Triassic) -- A more advanced "galesaurid" cynodont. Further development of several of the cynodont features seen already. Temporal fenestra still larger, larger jaw muscle attachments. Bony secondary palate almost complete. Functional division of teeth: incisors (four uppers and three lowers), canines, and then 7-9 cheek teeth with cusps for chewing. The cheek teeth were all alike, though (no premolars & molars), did not occlude together, were all single- rooted, and were replaced throughout life in alternate waves. Dentary still larger, with the little quadrate and articular bones were loosely attached. The stapes now touched the inner side of the quadrate. First sign of the mammalian jaw hinge, a ligamentous connection between the lower jaw and the squamosal bone of the skull. The occipital condyle is now two slightly separated surfaces, though not separated as far as the mammalian double condyles. Vertebral connections more mammalian, and lumbar ribs reduced. Scapula shows development of a new mammalian shoulder muscle. Ilium increased again, and all four legs fully upright, not sprawling. Tail short, as is necessary for agile quadrupedal locomotion. The whole locomotion was more agile. Number of toe bones is 2.3.4.4.3, intermediate between reptile number (2.3.4.5.4) and mammalian (2.3.3.3.3), and the "extra" toe bones were tiny. Nearly complete skeletons of these animals have been found curled up - a possible reaction to conserve heat, indicating possible endothermy? Adults and juveniles have been found together, possibly a sign of parental care. The specialization of the lumbar area (e.g. reduction of ribs) is indicative of the presence of a diaphragm, needed for higher O2 intake and homeothermy. NOTE on hearing: The eardrum had developed in the only place available for it -- the lower jaw, right near the jaw hinge, supported by a wide prong (reflected lamina) of the angular bone. These animals could now hear airborne sound, transmitted through the eardrum to two small lower jaw bones, the articular and the quadrate, which contacted the stapes in the skull, which contacted the cochlea. Rather a roundabout system and sensitive to low-frequency sound only, but better than no eardrum at all! Cynodonts developed quite loose quadrates and articulars that could vibrate freely for sound transmittal while still functioning as a jaw joint, strengthened by the mammalian jaw joint right next to it. All early mammals from the Lower Jurassic have this low-frequency ear and a double jaw joint. By the middle Jurassic, mammals lost the reptilian joint (though it still occurs briefly in embryos) and the two bones moved into the nearby middle ear, became smaller, and became much more sensitive to high-frequency sounds.
• Cynognathus (early Triassic, 240 Ma; suspected to have existed even earlier) -- We're now at advanced cynodont level. Temporal fenestra larger. Teeth differentiating further; cheek teeth with cusps met in true occlusion for slicing up food, rate of replacement reduced, with mammalian-style tooth roots (though single roots). Dentary still larger, forming 90% of the muscle-bearing part of the lower jaw. TWO JAW JOINTS in place, mammalian and reptilian: A new bony jaw joint existed between the squamosal (skull) and the surangular bone (lower jaw), while the other jaw joint bones were reduced to a compound rod lying in a trough in the dentary, close to the middle ear. Ribs more mammalian. Scapula halfway to the mammalian condition. Limbs were held under body. There is possible evidence for fur in fossil pawprints.
• Diademodon (early Triassic, 240 Ma; same strata as Cynognathus) -- Temporal fenestra larger still, for still stronger jaw muscles. True bony secondary palate formed exactly as in mammals, but didn't extend quite as far back. Turbinate bones possibly present in the nose (warm-blooded?). Dental changes continue: rate of tooth replacement had decreased, cheek teeth have better cusps & consistent wear facets (better occlusion). Lower jaw almost entirely dentary, with tiny articular at the hinge. Still a double jaw joint. Ribs shorten suddenly in lumbar region, probably improving diaphragm function & locomotion. Mammalian toe bones (2.3.3.3.3), with closely related species still showing variable numbers.
• Probelesodon (mid-Triassic; South America) -- Fenestra very large, still separate from eyesocket (with postorbital bar). Secondary palate longer, but still not complete. Teeth double-rooted, as in mammals. Nares separated. Second jaw joint stronger. Lumbar ribs totally lost; thoracic ribs more mammalian, vertebral connections very mammalian. Hip & femur more mammalian.
• Probainognathus (mid-Triassic, 239-235 Ma, Argentina) -- Larger brain with various skull changes: pineal foramen ("third eye") closes, fusion of some skull plates. Cheekbone slender, low down on the side of the eye socket. Postorbital bar still there. Additional cusps on cheek teeth. Still two jaw joints. Still had cervical ribs & lumbar ribs, but they were very short. Reptilian "costal plates" on thoracic ribs mostly lost. Mammalian #toe bones.
• Exaeretodon (mid-late Triassic, 239Ma, South America) -- (Formerly lumped with the herbivorous gomphodont cynodonts.) Mammalian jaw prong forms, related to eardrum support. Three incisors only (mammalian). Costal plates completely lost. More mammalian hip related to having limbs under the body. Possibly the first steps toward coupling of locomotion & breathing. This is probably a "cousin" fossil not directly ancestral, as it has several new but non-mammalian teeth traits.

• Oligokyphus, Kayentatherium (early Jurassic, 208 Ma) -- These are tritylodontids, an advanced cynodont group. Face more mammalian, with changes around eyesocket and cheekbone. Full bony secondary palate. Alternate tooth replacement with double-rooted cheek teeth, but without mammalian-style tooth occlusion (which some earlier cynodonts already had). Skeleton strikingly like egg- laying mammals (monotremes). Double jaw joint. More flexible neck, with mammalian atlas & axis and double occipital condyle. Tail vertebrae simpler, like mammals. Scapula is now substantially mammalian, and the forelimb is carried directly under the body. Various changes in the pelvis bones and hind limb muscles; this animal's limb musculature and locomotion were virtually fully mammalian. Probably cousin fossils (?), with Oligokyphus being more primitive than Kayentatherium. Thought to have diverged from the trithelodontids during that gap in the late Triassic. There is disagreement about whether the tritylodontids were ancestral to mammals (presumably during the late Triassic gap) or whether they are a specialized offshoot group not directly ancestral to mammals.
• Pachygenelus, Diarthrognathus (earliest Jurassic, 209 Ma) -- These are trithelodontids, a slightly different advanced cynodont group. New discoveries (Shubin et al., 1991) show that these animals are very close to the ancestry of mammals. Inflation of nasal cavity, establishment of Eustachian tubes between ear and pharynx, loss of postorbital bar. Alternate replacement of mostly single- rooted teeth. This group also began to develop double tooth roots -- in Pachygenelus the single root of the cheek teeth begins to split in two at the base. Pachygenelus also has mammalian tooth enamel, and mammalian tooth occlusion. Double jaw joint, with the second joint now a dentary-squamosal (instead of surangular), fully mammalian. Incipient dentary condyle. Reptilian jaw joint still present but functioning almost entirely in hearing; postdentary bones further reduced to tiny rod of bones in jaw near middle ear; probably could hear high frequencies now. More mammalian neck vertebrae for a flexible neck. Hip more mammalian, with a very mammalian iliac blade & femur. Highly mobile, mammalian-style shoulder. Probably had coupled locomotion & breathing. These are probably "cousin" fossils, not directly ancestral (the true ancestor is thought to have occurred during that late Triassic gap). Pachygenelus is pretty close, though.
• Adelobasileus cromptoni (late Triassic; 225 Ma, west Texas) -- A recently discovered fossil proto-mammal from right in the middle of that late Triassic gap! Currently the oldest known "mammal." Only the skull was found. "Some cranial features of Adelobasileus, such as the incipient promontorium housing the cochlea, represent an intermediate stage of the character transformation from non-mammalian cynodonts to Liassic mammals" (Lucas & Luo, 1993). This fossil was found from a band of strata in the western U.S. that had not previously been studied for early mammals. Also note that this fossil dates from slightly before the known tritylodonts and trithelodonts, though it has long been suspected that tritilodonts and trithelodonts were already around by then. Adelobasileus is thought to have split off from either a trityl. or a trithel., and is either identical to or closely related to the common ancestor of all mammals.
• Sinoconodon (early Jurassic, 208 Ma) -- The next known very ancient proto-mammal. Eyesocket fully mammalian now (closed medial wall). Hindbrain expanded. Permanent cheekteeth, like mammals, but the other teeth were still replaced several times. Mammalian jaw joint stronger, with large dentary condyle fitting into a distinct fossa on the squamosal. This final refinement of the joint automatically makes this animal a true "mammal". Reptilian jaw joint still present, though tiny.
• Kuehneotherium (early Jurassic, about 205 Ma) -- A slightly later proto-mammal, sometimes considered the first known pantothere (primitive placental-type mammal). Teeth and skull like a placental mammal. The three major cusps on the upper & lower molars were rotated to form interlocking shearing triangles as in the more advanced placental mammals & marsupials. Still has a double jaw joint, though.
• Eozostrodon, Morganucodon, Haldanodon (early Jurassic, ~205 Ma) -- A group of early proto-mammals called "morganucodonts". The restructuring of the secondary palate and the floor of the braincase had continued, and was now very mammalian. Truly mammalian teeth: the cheek teeth were finally differentiated into simple premolars and more complex molars, and teeth were replaced only once. Triangular- cusped molars. Reversal of the previous trend toward reduced incisors, with lower incisors increasing to four. Tiny remnant of the reptilian jaw joint. Once thought to be ancestral to monotremes only, but now thought to be ancestral to all three groups of modern mammals -- monotremes, marsupials, and placentals.
• Peramus (late Jurassic, about 155 Ma) -- A "eupantothere" (more advanced placental-type mammal). The closest known relative of the placentals & marsupials. Triconodont molar has with more defined cusps. This fossil is known only from teeth, but judging from closely related eupantotheres (e.g. Amphitherium) it had finally lost the reptilian jaw joint, attaing a fully mammalian three-boned middle ear with excellent high-frequency hearing. Has only 8 cheek teeth, less than other eupantotheres and close to the 7 of the first placental mammals. Also has a large talonid on its "tribosphenic" molars, almost as large as that of the first placentals -- the first development of grinding capability.
• Endotherium (very latest Jurassic, 147 Ma) -- An advanced eupantothere. Fully tribosphenic molars with a well- developed talonid. Known only from one specimen. From Asia; recent fossil finds in Asia suggest that the tribosphenic molar evolved there.
• Kielantherium and Aegialodon (early Cretaceous) -- More advanced eupantotheres known only from teeth. Kielantherium is from Asia and is known from slightly older strata than the European Aegialodon. Both have the talonid on the lower molars. The wear on it indicates that a major new cusp, the protocone, had evolved on the upper molars. By the Middle Cretaceous, animals with the new tribosphenic molar had spread into North America too (North America was still connected to Europe.)
• Steropodon galmani (early Cretaceous) -- The first known definite monotreme, discovered in 1985.
• Vincelestes neuquenianus (early Cretaceous, 135 Ma) -- A probably-placental mammal with some marsupial traits, known from some nice skulls. Placental-type braincase and coiled cochlea. Its intracranial arteries & veins ran in a composite monotreme/placental pattern derived from homologous extracranial vessels in the cynodonts. (Rougier et al., 1992)
• Pariadens kirklandi (late Cretaceous, about 95 Ma) -- The first definite marsupial. Known only from teeth.
• Kennalestes and Asioryctes (late Cretaceous, Mongolia) -- Small, slender animals; eyesocket open behind; simple ring to support eardrum; primitive placental-type brain with large olfactory bulbs; basic primitive tribosphenic tooth pattern. Canine now double rooted. Still just a trace of a non-dentary bone, the coronoid, on the otherwise all-dentary jaw. "Could have given rise to nearly all subsequent placentals." says Carroll (1988).
• Cimolestes, Procerberus, Gypsonictops (very late Cretaceous) -- Primitive North American placentals with same basic tooth pattern.

At some point you're going to have to come to some kind of truce with reality.