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Posted on 08/13/2003 9:02:05 PM PDT by nwrep
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2 hours, 55 minutes ago
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By RAMOLA TALWAR BADAM, Associated Press Writer
BOMBAY, India - U.S. and Indian scientists said Wednesday they have discovered a new carnivorous dinosaur species in India after finding bones in the western part of the country.
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The new dinosaur species was named Rajasaurus narmadensis, or "Regal reptile from the Narmada," after the Narmada River region where the bones were found.
The dinosaurs were between 25-30 feet long, had a horn above their skulls, were relatively heavy and walked on two legs, scientists said. They preyed on long-necked herbivorous dinosaurs on the Indian subcontinent during the Cretaceous Period at the end of the dinosaur age, 65 million years ago.
"It's fabulous to be able to see this dinosaur which lived as the age of dinosaurs came to a close," said Paul Sereno, a paleontologist at the University of Chicago. "It was a significant predator that was related to species on continental Africa, Madagascar and South America."
Working with Indian scientists, Sereno and paleontologist Jeff Wilson of the University of Michigan reconstructed the dinosaur skull in a project funded partly by the National Geographic (news - web sites) Society.
A model of the assembled skull was presented Wednesday by the American scientists to their counterparts from Punjab University in northern India and the Geological Survey of India during a Bombay news conference.
Scientists said they hope the discovery will help explain the extinction of the dinosaurs and the shifting of the continents — how India separated from Africa, Madagascar, Australia and Antarctica and collided with Asia.
The dinosaur bones were discovered during the past 18 years by Indian scientists Suresh Srivastava of the Geological Survey of India and Ashok Sahni, a paleontologist at Punjab University.
When the bones were examined, "we realized we had a partial skeleton of an undiscovered species," Sereno said.
The scientists said they believe the Rajasaurus roamed the Southern Hemisphere land masses of present-day Madagascar, Africa and South America.
"People don't realize dinosaurs are the only large-bodied animal that lived, evolved and died at a time when all continents were united," Sereno said.
The cause of the dinosaurs' extinction is still debated by scientists. The Rajasaurus discovery may provide crucial clues, Sereno said.
India has seen quite a few paleontological discoveries recently.
In 1997, villagers discovered about 300 fossilized dinosaur eggs in Pisdura, 440 miles northeast of Bombay, that Indian scientists said were laid by four-legged, long-necked vegetarian creatures.
Indian scientists said the dinosaur embryos in the eggs may have suffocated during volcanic eruptions.
But not from the cooling of lava, as you seem to believe.
Granite only forms deep under the surface, where magma can cool slowly enough and under enough pressure for the crystalline structure of granite to form.
On the surface of the Earth, lava cools into basalt, a very different kind of rock, which will not turn into granite no matter how long you leave it lying around on the surface.
What is going to happen to the ash and lava flows of M.S.H. in a few hundred years?
They're going to remain ash and basalt in timespans as short as "a few hundred years".
How about the trees that are in Spirit Lake?
They'll still be trees, albeit considerably more rotted.
There are upright petrified trees all over the world that cut straight through the sacred geological column.
No, there aren't. And the geologic column is not "sacred" -- you've got geologists confused with someone else.
There are, however, fossil trees which extend through one or more stratigraphic layers which were rapidly deposited onto the trees, burying them.
For the lurkers: For far longer than they should (since at least 1975), creationists have been beating a dead horse that they call "polystrate trees". These are trees (or more often, stumps of trees) found standing fossilized vertically. Aha!, cry the creationists, if the stump is 30 feet tall, then clearly the 30 feet (measured vertically) of rock around the tree couldn't have been deposited over millions of years, therefor geology is bunk!
The problem with this, as has been pointed out to them countless times, is that although the *entire* geologic column has taken hundreds of millions of years to accumulate, this hardly means that any particular foot of it had to have been "grown" with glacierlike slowness. On the contrary, ordinary river floods, landslides, volcanic eruptions, etc. can at times deposit dozens or hundreds of feet within days. "Polystrate" trees can result when the location the tree had been growing gets inundated several times in a few years (or once, if a big one), burying a significant portion of the tree trunk (the fossilized trees often look "cut off" above a certain point, where deposition had stopped long enough for the top of the tree to be rotted or eroded away before the next cycle of deposition).
What's funny is that this process was recognized by geologists as early as *1868* (Dawson, J.W., 1868. Acadian Geology. The Geological Structure, Organic Remains, and Mineral Resources of Nova Scotia, New Brunswick, and Prince Edward Island, 2nd edition. MacMillan and Co.: London, 694pp).
But the creationists seem to be slow catching up sometimes.
If that column formed over millions and millions of years, the tree would have rotted and turned to dust.
Right. So it didn't. Not the 10-20 foot portion immediately around the tree, anyway. But that doesn't mean that the *mile* or more of column above and below the tree happened all overnight, does it?
These trees are perfectly preserved.
Hardly, but they are recognizeable.
Mt. St. Helens shows how this likely happened.
No, it doesn't. Your link provided very shoddy argument which boils down to, "some debarked, limbless stumps with a few root stubs clinging to them landed root-down in the lake bottom, therefor scientists wouldn't be able to distinguish them from trees which had fossilized where they grew". Not only is that an insult to the profession, it's untrue. Take, for example, the following description of "in place" trees, and how many different ways it was possible to determine that they were where they had grown, and not blown there by a volcanic explosion: Fossil trees trunks
Your link makes another fallacious claim as well. It says that because some of the sunken trees have landed a few feet higher/lower than others, that this might "explain" layered forests in the geologic column. Um, no. Layered forests in the geologic column are hardly separated by "a few feet". For example, in the Joggins section of the Bay of Fundy, along a 50 kilometer section of sea cliff, is visible a 2750 meter-thick cross-section of the geologic column, with *multiple* layers of in-place forests, separated by up to *hundreds* of feet of strata. The forests are mature, layered atop each other (with large separation), upright trunks, and *in-place roots* resting in layers of well-developed soil.
This is the kind of evidence ICR tries to lamely explain away by saying, "well, some of the trees blasted by Mount Saint Helens ended up a few feet higher or lower in the lake bed..." Sheesh.
Actually, most evidence for an "old Earth" comes from lines of evidence other than the geologic column.
Just out of curiosity, though, exactly where did you "learn" that the geologic column is somehow the only source of such information? Your reply may be instructive.
You do not base it upon dating methods such as Carbon 14
Of course not, because Carbon-14 dating caps out at around 60,000 years. Did you not now that?
or Potassium Argon because both do not work.
*snicker*. You are invited to present your evidence. Make sure that your "proof" does not consist of the obvious fact that K-Ar dating (or any other dating method) will give incorrect results if used on a clearly inappropriate sample.
The dates come from some man's theory
Yeah, nuclear physics, "just some man's theory"...
Perhaps you could also explain why samples dated by multiple independent methods (up to as many as ten, sometimes), all based on "different men's theories", give DATES THAT AGREE WITH EACH OTHER. What an amazing coincidence, eh?
and I don't care if you find it absurd, there is ample evidence that the earth is young.
Such as?
If you could get passed the geological column, then maybe you could see this.
If you could get off the geologic column, you might find a field where you won't keep making incorrect claims.
Not true. It is done by who is against evolution as I showed quite well in Post# 2619 of the Pheobe Debates thread.
Careful, now you're contradicting the creationists who admit that "microevolution" can create new species out of old ones, as long as they stay within the same "kind". Otherwise, they get tied into all kinds of knots explaining how, for example, dachshunds could be descendants of wolves.
You do not have ANYTHING that turns a fish into a dog though. NOTHING.
Oh? Try this on for size:
Those are actual fossil finds. Isn't it... curious that when you lay them out chronologically (or bottom-to-top in the geologic column, since you're being so skeptical about dating methods), it makes a sequence that plays like frames from an animation of a fish morphing into a dog?Fish to Amphibian transition: 1. Cheirolepis, (early Devonian, 400 million years ago) -- Primitive bony ray-finned fishes that gave rise to the vast majority of living fish. Heavy acanthodian-type scales, acanthodian-like skull, and big notocord.
2. Osteolepis (mid-Devonian, 390 million years ago) -- One of the earliest crossopterygian lobe-finned fishes, still sharing some characters with the lungfish (the other lobe-finned fishes). Had paired fins with a leg-like arrangement of major limb bones, capable of flexing at the "elbow", and had an early-amphibian-like skull and teeth.
3. Eusthenopteron, Sterropterygion (mid-late Devonian, 380 million years ago) -- Early rhipidistian lobe-finned fish roughly intermediate between early crossopterygian fish and the earliest amphibians. Skull very amphibian-like. Strong amphibian- like backbone. Fins very like early amphibian feet in the overall layout of the major bones, muscle attachments, and bone processes, with tetrapod-like tetrahedral humerus, and tetrapod-like elbow and knee joints. But there are no perceptible "toes", just a set of identical fin rays. Body & skull proportions rather fishlike.
4. Panderichthys, Elpistostege (mid-late Devonian, about 370 Mya) -- These "panderichthyids" are very tetrapod-like lobe-finned fish. Unlike Eusthenopteron, these fish actually look like tetrapods in overall proportions (flattened bodies, dorsally placed orbits, frontal bones! in the skull, straight tails, etc.) and have remarkably foot-like fins.
5. Obruchevichthys(middle Late Devonian, about 370 Mya -- Discovered in 1991 in Scotland, these are the earliest known tetrapod remains. The humerus is mostly tetrapod-like but retains some fish features. The discoverer, Ahlberg (1991), said: "It [the humerus] is more tetrapod-like than any fish humerus, but lacks the characteristic early tetrapod 'L-shape'...this seems to be a primitive, fish-like character....although the tibia clearly belongs to a leg, the humerus differs enough from the early tetrapod pattern to make it uncertain whether the appendage carried digits or a fin. At first sight the combination of two such extremities in the same animal seems highly unlikely on functional grounds. If, however, tetrapod limbs evolved for aquatic rather than terrestrial locomotion, as recently suggested, such a morphology might be perfectly workable."
6. Hynerpeton, Acanthostega, Ichthyostega (late Devonian, 360 Mya) -- A little later, the fin-to-foot transition was almost complete, and we have a set of early tetrapod fossils that clearly did have feet. The most complete are Ichthyostega, Acanthostega gunnari, and the newly described Hynerpeton bassetti (Daeschler et al., 1994). (There are also other genera known from more fragmentary fossils.) Hynerpeton is the earliest of these three genera (365 Ma), but is more advanced in some ways; the other two genera retained more fish- like characters longer than the Hynerpeton lineage did. Acanthostega still had internal gills, adding further support to the suggestion that unique tetrapod characters such as limbs with digits evolved first for use in water rather than for walking on land. Acanthostega also had a remarkably fish-like shoulder and forelimb. Ichthyostega was also very fishlike, retaining a fish-like finned tail, permanent lateral line system, and notochord. It turns out that Acanthostega's front foot had eight toes, and Ichthyostega's hind foot had seven toes, giving both feet the look of a short, stout flipper with many "toe rays" similar to fin rays. All you have to do to a lobe- fin to make it into a many-toed foot like this is curl it, wrapping the fin rays forward around the end of the limb. In fact, this is exactly how feet develop in larval amphibians, from a curled limb bud. Hynerpeton, in contrast, probably did not have internal gills and already had a well-developed shoulder girdle; it could elevate and retract its forelimb strongly, and it had strong muscles that attached the shoulder to the rest of the body (Daeschler et al., 1994).
7. Labyrinthodonts (eg Pholidogaster, Pteroplax) (late Dev./early Miss., 355 Mya) -- These larger amphibians still have some icthyostegid fish features, such as skull bone patterns, labyrinthine tooth dentine, presence & pattern of large palatal tusks, the fish skull hinge, pieces of gill structure between cheek & shoulder, and the vertebral structure. But they have lost several other fish features: the fin rays in the tail are gone, the vertebrae are stronger and interlocking, the nasal passage for air intake is well defined, etc.
Amphibian to Reptile transition: 8. Pholidogaster (Mississippian, about 330 Ma) -- A group of large labrinthodont amphibians, transitional between the early amphibians (the ichthyostegids, described above) and later amphibians such as rhachitomes and anthracosaurs.
9. Proterogyrinus (late Mississippian, 325 Mya) -- Classic labyrinthodont-amphibian skull and teeth, but with reptilian vertebrae, pelvis, humerus, and digits. Still has fish skull hinge. Amphibian ankle. 5-toed hand and a 2-3-4-5-3 (almost reptilian) phalangeal count.
10. Limnoscelis, Tseajaia (late Carboniferous, 300 Mya) -- Amphibians apparently derived from the early anthracosaurs, but with additional reptilian features: structure of braincase, reptilian jaw muscle, expanded neural arches.
11. Solenodonsaurus (mid-Pennsylvanian) -- An incomplete fossil, apparently between the anthracosaurs and the cotylosaurs. Loss of palatal fangs, loss of lateral line on head, etc. Still just a single sacral vertebra, though.
12. Hylonomus, Paleothyris (early Pennsylvanian) -- These are protorothyrids, very early cotylosaurs (primitive reptiles). They were quite little, lizard-sized animals with amphibian-like skulls (amphibian pineal opening, dermal bone, etc.), shoulder, pelvis, & limbs, and intermediate teeth and vertebrae. Rest of skeleton reptilian, with reptilian jaw muscle, no palatal fangs, and spool-shaped vertebral centra. Probably no eardrum yet.
13. Paleothyris (early Pennsylvanian) -- An early captorhinomorph reptile, with no temporal fenestrae at all.
14. Protoclepsydrops haplous (early Pennsylvanian) -- The earliest known synapsid reptile. Little temporal fenestra, with all surrounding bones intact. Had amphibian-type vertebrae with tiny neural processes. (reptiles had only just separated from the amphibians)
15. Clepsydrops (early Pennsylvanian) -- The second earliest known synapsid.
Reptile to Mammal transition: 16. 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.
17. 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".
18. 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.
19. 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.
20. 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.
21. 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.
22. 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.
23. 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.
24. 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.
25. 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.
26. 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.
27. 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.
28. Pachygenelus, Diarthrognathus (earliest Jurassic, 209 Ma) -- These are trithelodontids. 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.
29. 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.
Proto-mammal to Placental Mammal transition: 30. 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.
31. 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.
32. 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.
33. 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.
34. 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)
35. 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).
Placental mammal to dog transition: 35. Protungulatum (latest Cretaceous) -- Transitional between earliest placental mammals and the condylarths (primitive, small hoofed animals). These early, simple insectivore- like small mammals had one new development: their cheek teeth had grinding surfaces instead of simple, pointed cusps. They were the first mammal herbivores. All their other features are generalized and primitive -- simple plantigrade five-toed clawed feet, all teeth present (3:1:4:3) with no gaps, all limb bones present and unfused, pointy-faced, narrow small brain, eyesocket not closed.36. Creodonts -- early placental mammals with minor but interestingly carnivore-like changes in the molars and premolars. Had a carnivore- like shearing zone in the teeth, though the zone moved throughout life instead of staying in particular teeth. Also had a carnivore- like bony sheet in the brain dividing cerebrum & cerebellum, details of ankle. Closely related to & possibly ancestral to carnivores.
37. Cimolestes (late Cretaceous) -- This creodont (?) lost the last molar & then later enlarged the last upper premolar and first lower molar. (In modern carnivores, these two teeth are very enlarged to be the wickedly shearing carnassial teeth, the hallmark of carnivores.) Still unfused feet & unossified bulla. This genus is probably ancestral to two later lines of Eocene carnivores called "miacoids". Miacoids were relatively unspecialized meat-eaters that seem to have split into a "viverravid" line (with cat/civet/hyena traits) and a "miacid" line (with dog/bear/weasel traits).
38. Cimolestes sp. (Paleocene) -- A later, as yet unnamed species that has very miacid-like teeth.
39. Paroodectes, Vulpavus (early Eocene) -- Early miacids. Enlarged carnassials now specialized for shearing. Still had unfused foot bones, short limbs, plantigrade feet, unossified bulla.
40. Cynodictis (late Eocene) -- First known arctoid (undifferentiated dog/bear).
41. Hesperocyon (early Oligocene) -- A later arctoid. Compared to miacids like Paroodectes, limbs have elongated, carnassials are more specialized, braincase is larger. From here, the main line of canid evolution can be traced in North America, with bears branching out into a Holarctic distribution.
42. Cynodesmus (Miocene) -- First true dog. The dog lineage continued through Tomarctus (Pliocene) to the modern dogs, wolves, & foxes, Canis (Pleistocene).
[Compiled from Kathleen Hunt's Transitional Vertebrate Fossil FAQ]
Let's leave aside the issue of whether any of these actually did evolve from another, since I know you're going to fight that concept as well. So just focus on one question: If you believe in microevolution, does any *one* step in the above sequence seem impossible to you? More to the point, would any transition from "N" to "N+1" be large enough that you wouldn't write them off as "just microevolution"?
And yet, when put together, wouldn't all those "microevolutions" end up changing a fish into a dog?
And if it didn't happen that way, why are there so many fossils which fit so neatly into a transitional sequence as if they had? And why can we list similar fossil lineages for the rise of any other modern species you'd care to name?
It is absurd to think that something came from nothing.
Yes it is, which is why biologists don't claim that.
That impersonal matter created highly complex personal beings. THAT is what is absurd.
The fact that you find it absurd does not make it not true.
it boggles the mind, how something can be right in front of somebody and yet they still deny it.
Yes... Doesn't it...
It does, doesn't it. It boggles the mind that someone could see a baby in the womb and say "chance."
It boggles the mind that anyone can still think that there's nothing more to the process of evolution that just "chance", despite the fact that any schoolbook on the subject lists the non-chance components of the process.
It boggles the mind that one could see the complexity of an eyeball that is so complex that it is IMPOSSIBLE for it to evolve-
Okay, I'll bite, why is it "impossible"?
The complexity and beauty of God's creation is all around us and it is stunning that people will still scream "random processes of natural selection."
Natural selection is *not* random. Please learn more about evolution before you attempt to critique it.
It is called willful ignorance, and it is VERY sad.
And what is your presumption that everyone who disagrees with you must be doing so out of "ignorance"?
I've long tried to figure out why creationists keep accusing scientists of "uniformity". Science does *not* presume "uniformity" in the way that creationists mean it, and haven't for well over 100 years. Geologists, for example, are well aware of such non-uniform occurrences as floods, earthquakes, meteor strikes, volcanic eruptions, and so on. True "uniformitarians" haven't existed for ages.
Another biggy is that the geological column is correct.
Are you somehow asserting that it's *not* "correct"? That the geologic column doesn't actually exist or something? Or that it's somehow a fake? If so, who piled up all those rock layers to fool us?
These "branches of knowledge" invalidate themselves in many cases
Examples, please.
and "scientists" go back to the drawing board to try to come up with a better theory that will explain the impossible.
Which "impossible" things do you think scientists are trying to explain? I know a few who are trying to explain impossible things like vapor canopies and global floods, but they're hardly representative...
Evolution says in the beginning nothing exploded.
Um, no, it doesn't. Would you kindly tell us where you "learned" this?
And out of nothing, there was molten lava that got rained on for millions-billions of years
You sort of left out a few steps...
( a figure that crawfishes all the time),
"All the time", eh? Please inform us of the last time the accepted age of the Earth was modified by over 10%.
and whalah- one day, we had man- all by chance, all contrary to the rules of reason.
Evolution is not "chance". Again, you might want to learn more about it before you attempt to dispute it.
Evolution is a fantasy. It is not science.
You have yet to make a case for such a belief. Note that attacking an oversimplified, inaccurate representation of it is not a refutation of evolution itself, it is a fallacy called the "straw man attack".
That's because "many people" fail to take into account why a process which includes variation, reproduction, and selection is very different from erosion, and is capable of much more.
If you're going to make an analogy, make sure it's a valid comparison.
If you're going to make a comment, make sure you understand the English language.
a·nal·o·gy 
( P ) Pronunciation Key (
-n
l
-j
)
n. pl. a·nal·o·gies
If you're going to make a comment, make sure you understand the English language.
You've retracted two of your hasty smartass remarks in this thread already, would you like to make it three?
Or shall I demonstrate that you have dishonestly left off the dictionary definition which encompasses the word as I was using it, and that I have hardly failed to understand the English language?
Your move.
No, your move.
No, your move.
You took your definition from dictionary.com. But you only posted the #1 entry, in a childish attempt to make it look as if I had used a word inappropriately.
The #3 entry in the definition, which you dishonestly left off, is as follows:
3. A form of logical inference or an instance of it, based on the assumption that if two things are known to be alike in some respects, then they must be alike in other respects.The analogy you were making in post #354 was:
Wind and a little time turns sandstone into arches that resemble flying buttresses. It does not follow, to many people, that more time using the same process will result in the formation of Notre Dame Cathedral.This was in reply to StolarStorm's:
If you have a creature and you make minor changes (micro-evolution) eventually you will have so many changes that you can't recognize what the creature looked like in the beginning... that is macro evolution.You were comparing two things (erosion and evolution) by saying that since the processes were alike in some respects (both can craft something new through the continued application of small changes) then since erosion can't result in something as complicated as Notre Dame Cathedral, then a reasonable inference for many people is that evolution might not proceed to intricate complexity either.
This is a classic analogy -- reasoning by analogy. Using knowledge of one process to presume things about another process believed to be somewhat similar.
I wouldn't have thought my use of the word to describe your example would be in any way remarkable, but apparently I underestimated your desire to dig really deep for a dishonest excuse to make a cheap shot.
So rather than deal with the substance of my post, you chose to go off on a classicly childish and completely unfounded "dictionary flame" (2), one of the lowest forms of cheap shots.
I even gave you an opportunity to reconsider and retract it, and you refused. This is, I must say, typical of you.
Now -- would you care to retract your trollish implication that *I'm* the one who needs to "make sure [they] understand the English language"? Or are you going to continue to act like an ass?
Your abusive language has been noted.
It seems from your profile that you assume all the sedimentary layers in the Grand Canyon sequence were laid down in one flood event, correct?
If so, how can you explain the presence of disconformities within the sequence? These are the result of subaerial exposure and erosion and so can't fit in with the flood model.
Mike
Out of curiosity, how would you feel about such things as the following, had they been posted by a signer of the agreement?
"...creationist witness fanatics who won't discuss or explain their ideology at all --- just cram it down everyone's throat!"Would you consider these examples to be somehow worse and more inflammatory than using the word "drunk" when trying to make a point about messed-up DNA structures?"reminds me of napoleans -- emperors --- in china THEY CALL THEM DIRT EMPERORS (( raving lunatics )) !"
"creationism has become a form of tribalism --- canibalism --- mindnaping --- slavery!"
"Flakes can't handle reality - truth when they're only hypeing bias - schlock ! They don't have an inkling or understanding in what they are doing - believing - preaching ... rote ideology --- trojan straw - stick ass and they call it science!"
"Creationism is a 2nd act play - farce ... w / o an act one and three --- clowns!"
"creationism is the most bigotted and racist abortion --- spiritual - intellectual rape - murder - tyranny!"
"Must be an admission ... that creationism is for the retarded - infantile and --- science is for the adult - intelligent!"
"independence of anything --- thinking is forbidden --- BLOCKED by infantile crippled minds --- radiation by lies - creationism!"
Would you feel more compelled to chastise a poster who said things like the above than you would to make an issue out of an indirect use of the word "drunk", for example?
Would you consider someone a hypocrit for obsessing over the word "drunk" as an inexcusable breach while overlooking such things as the above examples?
Would you call these "unnecessary" and "belittling"?
Why or why not?
And what would you propose be done about someone who wrote such things?
Absolutely pitiful. Are you reduced so soon to "snip-and-snipe" without owning up at all to your own behavior? Have you no shame?
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