Friday, December 21, 2012

No connection between dinosaurs and birds
Unlike most other saurischian dinosaurs, which have pubic bones that point forward, several groups of maniraptorans have an ornithischian-like backwards-pointing hip bone. A backward-pointing hip characterizes the therizinosaursdromaeosauridsavialans, and some primitive troodontids. The fact that the backward-pointing hip is present in so many diverse maniraptoran groups has led most scientists to conclude that the "primitive" forward-pointing hip seen in advanced troodontids and oviraptorosaurs is an evolutionary reversal, and that these groups evolved from ancestors with backward-pointing hips.[1]
Holtz and Osmólska (2004) diagnosed the clade Maniraptora based on the following characters: reduced or absent olecranon process of the ulnagreater trochanter and cranial trochanter of the femur fused into a trochanteric crestAn elongated, backwards-pointing pubic bone is present in therizinosauroids, dromaeosaurids, avialans, and the basal troodontid Sinovenator, which suggests that the propubic condition in advanced troodontids and oviraptorosaurs is a reversal.[1] Turner et al. (2007) named seven synapomorphies that diagnose Maniraptora.[4]
It [Scansoriopteryx] also had a pubis (hip bone) which pointed forward, a primitive trait among theropods, and unlike some maniraptorans more closely related to birds, where the pubis points downward or backward.[6]
"This information can be used to interpret patterns of locomotor evolution within Dinosauria. The evolution of quadrupedalism with large body size and the acquisition of cursorial or graviportal limb morphologies occurred repeatedly but did not affect the underlying uniformity of dinosaur locomotor morphology. Only derived coelurosaurian theropods (paravians) developed significant modifications of the basic dinosaurian patterns of limb use. Changes in theropod hindlimb kinematics and posture apparently began shortly prior to the origin of flight, but did not acquire a characteristically modern avian aspect until after the later acquisition of derived flight characteristics."
Again no connection between dinosaurs and birds.
But notice how it is worded, to not highlight that fact.

Another example of no connection between dinosaurs and birds:
"The antitrochanter serves as a brace to prevent abduction of the hindlimb and to absorb stresses that would otherwise be placed on the head of the femur during bipedal locomotion. The drum-in-trough-like form of the antitrochanter-femur articulation tends to assist in the transfer of long-axis rotational movements of the femur to the pelvis. The avian antitrochanter is a derived feature of birds that evolved as an aid in maintaining balance during bipedal terrestrial locomotion."

Theropod hips and hindlimbs show marked morphological changes (Fig. 3) that are consilient with functional changes during their evolution: (1) The antitrochanter repositioned from its primitive archosaurian location on the ischium, facing craniodorsally, to a more craniolateral orientation on the ischium and ilium in dinosaurs and their closest relatives. The antitrochanter then enlarged and re-oriented to face cranioventrally in birds. (2) The femoral head shifted from a craniomedial orientation in basal theropods to a more offset medial orientation in avetheropods, especially birds. (3) The ectocondylar tuber of the distal femur enlarged in “theropods” and moved distally from the proximal popliteal region onto the distal lateral condyle in birds. (4) The main weight-bearing axis of the crus shifted medially in theropods onto the tibia as the fibula and calcaneum were reduced, and elements of the knee and ankle joint became more rigidly appressed. (5) The fibular tubercle, the insertion of the knee flexor M. ilio-fibularis (Müller and Streicher, 1989), moved from a plesiomorphic craniolateral position on the proximal fibula in “theropods” to a caudolateral position in birds, consistent with a change in the action of this muscle related to increased knee flexion.

Notice the general pattern. Researchers see that characteristics appear for the first time in the primitive birds. Characteristics that are not found in dinos. But they just blandly acknowledge this and go on.
They never challenge their preconception that birds developed from dinos.
No matter how much contrary evidence accumulates.

It is not just feathers. Feathers is just the most dramatic example.
The azhdarchid mandibular joint is typical of pterosaurs in being a simple hinge permitting slight lateral movement of the mandible during jaw extension.

There are some marked differences in the bones of dinosaurs and birds: Dinosaurs had serrated teeth, while birds have peg-like teeth. Bird feet have reversed toes used for perching in branches - something dinosaurs never developed. Dinosaurs had a characteristic joint in their lower jaws for grasping prey - something never found in birds.


  1. The following is not related to the content of this post but I wanted to store it for future reference:
    "Both tiny birds and tiny pterosaurs dispensed with their long stiff tail. In birds it became a pygostyle. In pterosaurs the long stiff tail became a reduced, string-like tail with bead-like verts. Note the similarities in the pectoral girdles. Both could stand with their toes beneath their shoulder glenoids. Both had retroverted pedal digits but of two distinct designs. The anterior ilium of both taxa supported large thigh muscles. A large deltopectoral crest supported large flight adductors anchored to the sternum."

  2. More:
    "Only a few years ago it seemed that pterosaurs had three bones not found in other tetrapods: the prepubis, the pteroid and the preaxial carpal. Now these bones have been found in three fenestrasaur sister taxa, with Peters (2009) reporting on the latter two. Unfortunately, manuscripts reporting the appearance of the prepubis in Longisquama, Sharovipteryx and Cosesaurus were blackballed during the review process"

  3. More:
    oviraptorosaurs deviate most strongly from the "typical" and ancestral theropod morphologies."

    More of exactly what I have been pointing out.
    A primitive bird does not have the characteristic of a dinosaur.

  4. More that requires analysis:
    "Unlike most other saurischian dinosaurs, which have pubic bones that point forward, several groups of maniraptorans have an ornithischian-like backwards-pointing hip bone. A backward-pointing hip characterizes the therizinosaurs, dromaeosaurids, avialans, and some primitive troodontids. The fact that the backward-pointing hip is present in so many diverse maniraptoran groups has led most scientists to conclude that the "primitive" forward-pointing hip seen in advanced troodontids and oviraptorosaurs is an evolutionary reversal, and that these groups evolved from ancestors with backward-pointing hips.[1]

    An elongated, backwards-pointing pubic bone is present in therizinosauroids, dromaeosaurids, avialans, and the basal troodontid Sinovenator, which suggests that the propubic condition in advanced troodontids and oviraptorosaurs is a reversal.[1] Turner et al. (2007) named seven synapomorphies that diagnose Maniraptora.[4]

  5. And
    The wiki post says:

    "advanced troodontids and oviraptorosaurs have forward pointing pubic bones."
    It also says:

    "therizinosaurs have a backward-pointing hip"

    But research shows that these statements do not stand up.

  6. More:
    "Alvarezsauridae is an enigmatic family of small, long-legged running dinosaurs. Although originally thought to represent the earliest known flightless birds, a consensus of recent work suggests that they are primitive members of the Maniraptora."

  7. More:
    "Alvarezsauroids were originally considered to be a group of flightless birds, but it is now widely accepted that they are not nested within Aves (1–3) and instead represent a basal maniraptoran lineage."

    "Unlike other flightless birds, the ratites have no keel on their sternum—hence the name from the Latin ratis (for raft). Without this to anchor their wing muscles, they could not fly even if they were to develop suitable wings."

  9. Dinosaurs:
    Tyrannosaurs, Compsognathus, Ornitholestes, Therizinosaur
    Paraves, Alvarezsaurids, Oviraptors (likely secondarily flightless), Ornithomimids (likely secondarily flightless)

  10. More:

    As part of this, it would follow that alvaresaurids had backward pointing pubic bones. There does not seem to be much material on this, but see:
    "Patagonykus puertai Novas, 1997 Coniacian (LK) of Argentina
    This animal is apparently transitional between Alvarezsaurus and the rest of Parvicursorinae. It is known from vertebrae, coracoids, a forelimb, partial hips (weakly opisthopubic [pointing backwards, like in dromaeosaurids and birds]), and hindlimbs."

  11. The dino to bird folks make the following mistake:
    They take creatures like Alvarezsaurids as dinosaurs that were transitional to birds*. In fact, Alvarezsaurids are birds. Likely secondarily flightless birds.
    The dino to bird folk make that mistake because the Alvarezsaurid were likely land-based.

    Alvarezsaurids were "originally thought to represent the earliest known flightless birds"

    * although the dino to bird folks who think in terms of cladstics, do not even consider Alvarezsaurids as transitional because they only think of them as "sister taxa"

    "Mononykus is currently represented by a single holotype specimen, catalog number IGM N107/6. This specimen consists of a partial skeleton lacking a tail, and only small fragments of skull bones, including a complete braincase."
    In the Cretaceous Alvarezsauridae, the forelimbs are further transformed into bizarrely poweful arms with a huge thumb claw and exceedingly small digits II and III. The alvarezsaurids have a backwards pointing pubis. Unlike the therizinosauroid and ornithischian situation, this backwards position of the pubis is more likely associated with changes in the locomotory muscles towards knee-driven power from the ancestral tail-and-femur driven power.

  13. Feather cladogram showing that in regards to feathers that dinosaurs are not connected to birds:

    "No skin impressions have ever been found in association with fossils of Deinonychus. Nonetheless, the evidence suggests that the Dromaeosauridae, including Deinonychus, had feathers.[7] The genus Microraptor is both older geologically and more primitive phylogenetically than Deinonychus, and within the same family.[8] Multiple fossils of Microraptor preserve pennaceous, vaned feathers like those of modern birds on the arms, legs, and tail, along with covert and contour feathers.[7] Velociraptor is geologically younger than Deinonychus, but even more closely related (within the subfamily velociraptorinae, see Classification, below). A specimen of Velociraptor has been found with quill knobs on the ulna. Quill knobs are where the follicular ligaments attached, and are a direct indicator of feathers of modern aspect.[9]"

    "Despite receiving widespread attention in popular books on dinosaurs, and the usage of a complete mounted skeleton cast in museums throughout the world, Dromaeosaurus is surprisingly poorly known from actual fossils. The preparation of the popular cast by the Tyrrell Museum was only made possible by knowledge gained from other dromaeosaurids that have been discovered more recently."



    Another specimen of “Pterodactylus” that turned out to be even further removed phylogenetically is P. crassipes (aka Archaeopteryx lithographica).
    The Haarlem Specimen (TM 6428, also known as the Teyler Specimen) was discovered in 1855 near Riedenburg, Germany, and described as a Pterodactylus crassipes in 1877 by von Meyer. It was reclassified in 1970 by John Ostrom and is currently located at the Teylers Museum in Haarlem, Netherlands. It was the very first specimen, despite the classification error. It is also one of the least complete specimens, consisting mostly of limb bones and isolated cervical vertebrae and ribs.

    The first known Scaphognathus specimen was described in 1831 by August Goldfuss[1] who mistook the tailless specimen for a new Pterodactylus species: P. crassirostris.[2]

    they actually had proportionally short wings: the wing finger was abbreviated, with notably short distal-most phalanges