He had an enormous misshapen head, his jaw was so long that his two rows of teeth could not meet meaning he was unable to chew and his tongue was so large that he found it difficult to speak and drooled.----------
Giant Bug Terrorized Ancient Seas, 20 Mar 2009Excerpt: "This structure is unlike anything seen in other fossils or living arthropods," said Allison Daley, the team's lead researcher from Uppsala University in Sweden, who worked on the fossils for her doctoral thesis.
For example, Martialis has long and unusually segmented front legs, along with extended forceps-like mandibles that may be used to drag its prey from soil cavities.[snip]
The new species' genes suggest that it broke away from the main ant family before the origin of all other living ant groups, which include 20 subfamilies that together contain more than 12,000 species.
Some of these previously known ant groups do include blind, subterranean species, and recent molecular studies have suggested that these lineages appeared very early in ant evolution.
Also here: Blind ‘ants from mars’, By Peter N. Spotts| Staff Writer for The Christian Science Monitor/ September 18, 2008 edition
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T-Rexes, Supposed Pre-Humans, Cave Fish
and Cave Salamanders Are Products of Hedgehog
Signaling Gone Awry During Embryogenesis
by Yoel Natan
2 May 2008
I. Cave Fish and the T-Rex
IV. Data Gleaned From the Web
I. Cave Fish and the T-Rex
Although they were primarily carnivorous, a number of theropod families evolved herbivory during the Cretaceous Period.
So, could the T-Rex be descended from vegetarian theropods with Hedgehog (Hh) protein signaling gone awry during embryonic development--similar to the cave fish?
Italian wall lizards introduced to a tiny island off the coast of Croatia are evolving in ways that would normally take millions of years to play out, new research shows. In just a few decades the 5-inch-long (13-centimeter-long) lizards have developed a completely new gut structure, larger heads, and a harder bite, researchers say….What they found, however, was shocking. ‘The island was swarming with lizards,’ he said…. Pod Mrcaru, for example, had an abundance of plants for the primarily insect-eating lizards to munch on. Physically, however, the lizards were not built to digest a vegetarian diet.
Researchers found that the lizards developed cecal valves—muscles between the large and small intestine—that slowed down food digestion in fermenting chambers, which allowed their bodies to process the vegetation's cellulose into volatile fatty acids.
‘They evolved an expanded gut to allow them to process these leaves,’ Irschick said, adding it was something that had not been documented before. ‘This was a brand-new structure.’
Along with the ability to digest plants came the ability to bite harder, powered by a head that had grown longer and wider…. Such physical transformation in just 30 lizard generations takes evolution to a whole new level, Irschick said (“Lizards Rapidly Evolve After Introduction to Island,” by Kimberly Johnson, National Geographic News, April 21, 2008).
Of course, I don’t believe in their evolutionary mumbo-jumbo. There’s no way that new genetic information to create an additional stomach muscle could be generated spontaneously in 30 generations, and then passed to every lizard on the island via natural selection. Perhaps the lizard is a hybrid with a leaf-eating lizard, or the information for the muscle was in a recessive gene that natural selection selected for given the new environment. No matter how it occurred, this is just another example of speciation, not evolution. AiG has another explanation.
[Paleoneurologist] Professor Ralph Holloway, from Columbia University, New York, is an expert on ancient brains. His assessment of the Neanderthal skull was startling. It was 20% larger than the average size of a modern human's brain, and anatomically identical. He could tell that this Neanderthal was right-handed and that that the areas of brain responsible for complex thought were just as advanced as ours. He should have had the ability to think like us.
Bakewell, Zhang and a colleague found that substantially more genes in chimps evolved in ways that were beneficial than was the case with human genes. The results could be due to the fact that over the long term humans have had a smaller effective population size compared with chimps.
“Although there are now many more humans than chimps, in the past, human populations were much smaller, and may have been fragmented into even smaller groups,” Bakewell told LiveScience. So random events would play a more dominant role than natural selection in humans.
Here is why: Under the process of natural selection, gene variants that are beneficial get selected for and become more common in a population over time. But genetic drift, a random process in which chance “decides” which alleles survive, also occurs. In smaller populations, a fortuitous break for one or two alleles can have a disproportionately greater impact on the overall genes of that population compared with a larger one (“Chimps more evolved than humans: Study says more chimp genes changed in beneficial ways than human genes,” by Jeanna Bryner, LiveScience, April. 17, 2007).
Other evolutionists have said that humans nearly went extinct at least once.
One vivid demonstration of just how recent this move was is the fact that a cave fish and a surface fish can mate and produce healthy hybrids…(Zimmer, Carl. “Eyes, Part Two: Fleas, Fish, and the Careful Art of Deconstruction,” corante.com, 16 Feb 2005).
Thus, as with the case of cave fish and surface fish of the same species, Neanderthals interbred with humans and the offspring inherited only the normal Hedgehog (Hh) signaling, and so developed as normal humans. So, in one generation of interbreeding, the Neanderthals were no more. Any traits that they had that had nothing to do with Hedgehog mis-signaling would be preserved in the merged popu
| Attribute/Hedge-hog Attribute | Cave Fish | Cave Salamander | Tyrannosauridae Family | Cave Men |
| Small populations that live in remote areas | Yes, caves | Yes, true cave salamanders that spend all their time in caves are usually blind. | Yes, only 21 T-Rex specimens have been found in N America, and the Tyrannosauridae family is found only in N America and Mongolia. Carnivours are always few compared to herbivours and omnivours. | Yes. In B.C. times, the earth relatively unpopulated. Neanderthals were big-game hunters spread out thinly in the area bounded by England, Spain, Israel and the Caucasus. |
| Mid-section barrel-shaped | Yes, “more compressed body shape than surface fish” | No, slimming of the body | Yes, most theropods are slenderer | Yes, the average Neanderthal’s rib cage was larger |
| Stockier, muscular physiology, overall | ? | Yes, short muscular neck. | Modern humans are slender and not as big-boned as the Neanderthal. Cro-Magnon differs from modern humans only in being more robust and in cranium size. | |
| Limbs/legs/ arms/fins/neck shorter, longer, thinner, or thicker than related species, or are disproportionate to other body parts or overall body size | fins | The Texas Blind Salamander has thin, elongated limbs and thin body that accentuate its over-sized head. Salamanders have two pairs of legs, but some aquatic varieties has reduced limbs and keep their larval finned tail. | Yes. “T-Rex had longer femurs and legs than other theropods…” T-Rex had a 12 to 15 feet (3.7m to 4.6m) stride. The T-Rex had seemingly useless 1m-long arms. “…the predator Velociraptor has a lower arm bone that’s proportionally three times longer, a more useful six percent of its body length. T. rex had arms far shorter for its size than any other predatory dinosaur.” The similarly sized Allosaurus fragilis “had three fingers and a significantly larger forearm than T. rex, which had smaller forearms and only two fingers” used for grabbing and slashing prey. | The Neanderthal had a stocky build: larger kneecaps; longer collarbones & pelvic pubis; shorter shoulder blades, shin & calf bones. |
| Fingers/toes atrophied, bigger, or reduced count | ? | Salamanders have 4 toes on front feet and 5 on hind feet, but aquatic and cave varieties often have fewer. | Yes. The T-Rex and the Albertosaurus had only two fingers on each arm, and on each foot three clawed toes plus a dewclaw on a fourth atrophied toe. | The Neanderthal had larger fingertips. So-called pre-humans had bigger toes. |
| Canial flattened, over-sized | No | Yes. Similar carnivores had pointier jaws. | Yes, cranial space larger by 10+ percent in both Neanderthal and Cro-Magnon. The Neanderthal head was “a bit flatter and elongated, the chin is rounder.” | |
| Face protruding | Skulls are flatter and broader than surface varieties that tend to be bulbous. The Texas Blind Salamander has a large, wide head with flattened snout. | Yes, the T-Rex had a 1.5m-long head. | Yes, Neanderthal had heavy eyebrow ridges, and nose and jaw that protrudes, but the “missing” chin slopes back. | |
| Jaw and teeth stronger/over-sized | Larger jaws, more tastebuds, more maxillary teeth than surface fish of same variety. Thus, “cavefish outcompete surface fish for a limited amount of food when they share a darkened aquarium.” | ? | 1.2m jaws had 50 to 60 teeth up over 23cm long, as long as a forearm. | Archaic humans had larger front teeth. Neanderthal teeth are larger, and jaw matches protruding face, except it has “missing” chin. |
| Craniofacial features show remarkable change while the body shows little or no helpful adaptive change to the environment | Yes. The skull shape and contents are remarkable different, but the body differs only in having somewhat longer fins and lack of pigmentation. | Yes. The skull shape, and perhaps the brain contents, are remarkable different, but the body may differ only in having enlongated limbs or missing finger and toes. | Yes. The skull shape and jawbones, and perhaps the brain contents, are remarkable different, but the body differs only in having atrophied arms. It would have helped the T-Rex to have had useful arms, so this is not a helpful adaptation. | If it were not for their craniofacial features, the specimens thought to be transitional forms would have been identified as being merely human or pongid, within the realm of observed variability of each species, regardless of whether they were gracile, robust, or big boned. Questionable “DNA studies are the major basis on which the Neandertals are considered to be a separate species.” |
| Eyes small for body size, or degenerate | Yes (both) | Yes. Degenerate. “Reduced, vestigial eyes beneath the surface of the skin.” | The olfactory organ was larger “because of its poor eyesight.” Paleontologist Jack Horner of the Museum of the Rockies “maintains that its eyes were too small to see distant prey…” | In Neanderthal, the larger eye sockets suggesting larger eyes |
| Brain vision center smaller | ? | The T-Rex “had a very small optic region (so probably couldn’t see very well).” It’s optic nerve was normal sized for predator vision. Steroscopic images did provide depth perception, however. | The Neanderthal and Cro-Magnon may have had larger brain vision center since their brain cavity was 10% to 20% larger. The Neanderthal had larger eyes, too. | |
| Olfactory center over-sized | ? | Yes. “The T-Rex had the largest olfactory lobe of all the dinosaur species allowing it to smell prey (or decaying meat, blood or many other smells) from miles away.” “Their olfactory bulbs were the size of a grapefruit, and the bundle of olfactory nerves leading to the brain was wider than the spinal cord, judging by the size of the skull openings.” | The Neanderthal had a markedly larger nasal cavity | |
| Fish or amphibian had vibration sensors, or “lateral lines” | Yes, more, and more sensitive sensors | Yes, well-developed lateral lines similar to those of fish | Not applicable. | Not Applicable. |
| Brain vibration center larger | | Not applicable. | Not applicable. | |
| Inner ear over-sized | ? | ? | Slightly smaller | |
| Balance organ over-sized | | Likely larger since T-Rex is bipedal, not four-legged, the small arms would not counter-balance a T-Rex, and falls would be injurious, yet there’s no evidence that T-Rexes died from falls. | Slightly smaller since inner ear slightly smaller | |
| Brain balance center larger | ? | ? | Unknown, but overall brain 10% to 20% larger | |
| Short-term memory center larger | ? | ? | Unknown, but overall brain 10% to 20% larger | |
| Albino, or pigment degeneration | Yes (both) | Yes (both). The Texas Blind Salamander can be white to pale pink with translucent skin. | The T-Rex skin fossils have reptilian scales and are pebbly. Pigmentation was likely normal since mutants with bad skin would not survive prolonged exposure to the sun and live to sexual maturity. | Unknown, but some scientists say that automatically assuming that Neanderthal was dark-skinned is a racist notion. |
Excerpts:
One vivid demonstration of just how recent this move was is the fact that a cave fish and a surface fish can mate and produce healthy hybrids….
The most startling thing he has found is that cavefish grow eyes for quite a long time. Just as in surface fish, the brains of cave fish embryos bulge out to the sides, stretching into stalks that end in cups. A simple retina and lens begin to form, and growing nerves begin to link the retina to the visual centers of the fish brain. After about a day, however, the cavefish eye and surface fish eye begin to take different paths. The cave fish eye fails to develop an iris or a cornea, for example. Still, many parts of the cave fish eye continue to grow as their cells multiply….Despite being blind, the cavefish still retains its original circuit of eye-building genes….
Jeffery thinks that Hedgehog may be the key to understanding what’s really driving the evolution of cavefish. Like many genes involved in development, Hedgehog has many different jobs. It is known to be essential for the development of tastebuds, for example, as well as teeth and the bones that make up the head. And in cave fish, all of these features are significantly different from surface fish. It's possible that these changes are adaptations that help the cave fish feed more efficiently. These changes were only made possible by cranking up the production of Hedgehog. A side effect of this increase was the destruction of the cave fish eyes. But because eyes aren't essential in the dark, this wasn't such a big price to pay….
What's most remarkable about this choreography is that it has evolved again and again. Studies on Astyanax DNA suggest that populations of surface fish have repeatedly invaded caves, and each time they have gone blind. Jeffery and his colleagues have started comparing the development of embryos from different populations, and they find the cavefish have evolved blindness through the same patterns of gene activity….(Zimmer, Carl. “Eyes, Part Two: Fleas, Fish, and the Careful Art of Deconstruction,” corante.com, 16 Feb 2005).
Excerpts:
Cro-Magnon were anatomically modern, only differing from their modern day descendants in Europe by their more robust physiology and slightly larger brain capacity….
The Cro-Magnons must have come into contact with the Neanderthals, and are often credited with causing the latter's extinction, although morphologically modern humans seem to have coexisted with Neanderthals for some 60,000 years in the Levant and for more than 10,000 years in France.
Excerpt:
A characteristic pattern of mild facial anomalies, including small eye openings (i.e., short palpebral fissures), a thin upper lip, or flattened ridges between the base of the nose and the upper lip (i.e., a flattened philtrum) associated with FAS.
[From the illustration:] Skin folds at the corner of the eye, low nasal bridge, short nose, indistinct philtrum (groove between nose and upper lip), small head circumference, small eye opening, small midface, thin upper lip.
Hedgehog and holoprosencephaly (HPE)
Excerpt:
Cordero used a chemical aptly named cyclopamine to interfere with developmental signals sent by sonic hedgehog, a protein previously implicated in HPE. Although exposure early in development created cyclopic embryos, progressively later exposure mimicked the entire range of symptoms seen in children with HPE. Intriguingly, exposure after sonic hedgehog had already established itself in the divided brain affected only the embryo's face, and holding off just a bit longer resulted in no detectable malformation of either brain or beak.
"We've found that it's possible to recreate the entire spectrum of HPE defects seen in humans by disrupting sonic hedgehog at different times during development," said Helms, "which may explain why some children with HPE are more affected than others."
The scientists believe that HPE may arise from a combination of a faulty sonic hedgehog gene, present from conception, and varying times of exposure to environmental factors that further compromise the protein's signaling. In this scenario, early exposure leads to more severe defects and sometimes death, while later exposure can leave a child with only minor facial abnormalities (“Stanford Researcher’s Findings May Shed Light on Common, Deadly Birth Defect,” Lucile Packard Children’s Hospital, 16 Aug 2004).
Excerpt:
The scientists believe that HPE may arise from a combination of a faulty sonic hedgehog gene, present from conception, and varying times of exposure to environmental factors that further compromise the protein's signaling. In this scenario, early exposure leads to more severe defects and sometimes death, while later exposure can leave a child with only minor facial abnormalities.
Excerpt:
Symptoms range from death within days to severe mental retardation, seizures and an inability to speak. Others, however, suffer only mild learning disabilities. Facial defects can include a cleft lip, a single central incisor or "front tooth," close-set eyes or even a single eye in the center of the child's forehead.
Excerpt: In particular, we are investigating the role of Sonic hedgehog (Shh) signaling and the Tbx1 transcription factor during early craniofacial development. Shh has been shown to be involved in the growth, patterning and differentiation of several regions in the developing head and mutations in the Shh gene are responsible for holoprosencephaly, a severe congenital anomaly of midline craniofacial patterning.
Stooping Low for Evolution
http://www.answersingenesis.org/articles/am/v1/n1/stooping-low
Summary: A Turkish family with a genetic disorder claimed by evolutionists to be freaks and throwbacks to evolution.
http://en.wikipedia.org/wiki/Down_syndrome
Many of the common physical features of Down syndrome also appear in people with a standard set of chromosomes. They include a single transverse palmar crease (a single instead of a double crease across one or both palms), an almond shape to the eyes caused by an epicanthic fold of the eyelid, shorter limbs, poor muscle tone, and protruding tongue.
Symptoms: low nasal bridge, short nose, indistinct philtrum (groove between nose and upper lip), small head circumference, small eye opening, small midface, thin upper lip.
http://en.wikipedia.org/wiki/Epicanthic_fold
Excerpt: There is a wide distribution of the epicanthic fold across the world….
The maintenance of the epicanthic fold into adulthood in many populations is believed to have evolved as a defense against both the extreme cold as well as the extreme light[citation needed] that occurs in the Eurasian arctic and north. It has also been suggested that the fold provides some protection against dust[citation needed] in areas of desert such as that found in the deserts of northern China and Mongolia as well as parts of Africa.
Symptom: prominent supraorbital ridges
Excerpts:
…most paleoanthropologists also believe that there was at least some degree of cross-fertilization between Neandertals and modern humans. These two beliefs seem to represent a contradiction in the species concept in human evolution that requires clarification.
The “classic” Neandertal differs somewhat from the typical modern human—the Neandertal skull is a bit flatter and elongated, the chin is rounder, and the skeleton is more robust….
Among fossils usually classified as Neandertal are at least 26 individuals from six different sites who are clearly close to that subjective line which divides Neandertals from anatomically modern Homo sapiens….Evolutionists recognize these fossils as departing from the classic Neandertal morphology and describe them as “progressive” or “advanced” Neandertals. Their shape is sometimes explained as the result of gene flow (hybridization) with more modern populations….
Completing that continuum or gradation from Neandertals to modern humans are at least 107 individuals from five sites who are usually grouped with fossils categorized as anatomically modern humans. However, since they are close to that subjective line which divides them from the Neandertals, they are often described as “archaic moderns” or stated to have “Neandertal affinities” or “Neandertal features”…
Perhaps the strongest evidence that Neandertals were fully human and of our biblical “kind” is that at four sites people of Neandertal morphology and people of modern human morphology were buried together….
That Neandertals and anatomically modern humans were buried together constitutes strong evidence that they lived together, worked together, intermarried, and were accepted as members of the same family, clan, and community. The false distinction made by evolutionists today was not made by the ancients….
Although our emphasis has been upon burial, it is important to know that the Neandertals have a record of tender care for individuals before death. This has been established at Shanidar Cave, Iraq, and at the Bau de l’Aubesier Rock Shelter, France….
Fossils of large animals are found in association with Neandertal fossils at over half of the Neandertal sites….about half of the Neandertal sites that have fossil animal remains have fossils of elephants and woolly mammoths….
At Schöningen, Germany, were found three fir spears, fashioned like modern javelins, cleft at one end to accommodate stone points. They are the world’s oldest throwing spears, dated by evolutionists at about 400,000 years old. They are six to seven and one-half feet long, and required powerful people to use them. It proves that there were big-game hunters at that time, and suggests a long tradition of hunting with such tools. It is presumed that the Neandertals used them….
To shore up this approach, all the growing body of evidence for “art” before 40,000 years ago is simply dismissed and ignored….
Divje Babe Cave 1, Slovenia (northern Yugoslavia). A flute made from the thighbone of a cave bear used the same seven-note system as is found in western music, and it is associated with Mousterian tools. Mousterian tools are normally the type made by Neandertals….
Neanderthals had many adaptations to a cold climate, such as large braincase, short but robust builds, and large noses — traits selected by nature in cold climates. Their brain sizes have been estimated to be larger than modern humans, although such estimates have not been adjusted for their more robust builds. On average, Neanderthal males stood about 1.65 m tall (just under 5' 5") and were heavily built with robust bone structure. Females were about 1.53 to 1.57 m tall (about 5'–5'2").
Fossil skulls reveal the distinctively prominent brows and missing chins that set them apart from later humans.
Excerpt: The Neanderthals were fully bipedal and had a slightly larger average brain capacity than a typical modern human, though it is thought the brain structure may have been organized differently.
Excerpts:
Neanderthals have smaller canals than both modern humans and even earlier ancestors. This suggests they were less agile….
The Neanderthal vocal tract seems to have been shorter and wider than a modern male human's, closer to that found today in modern human females. It's possible, then, that Neanderthal males had higher pitched voices than we might have expected. Together with a big chest, mouth, and huge nasal cavity, a big, harsh, high, sound might have resulted. But, crucially, the anatomy of the vocal tract is close enough to that of modern humans to indicate that anatomically there was no reason why Neanderthal could not have produced the complex range of sounds needed for speech.
Excerpt:
A discovery by François Rouzaud of the French archaeological service suggests Neandertals were more sophisticated in their use of fire than previously believed. A burnt bear bone found deep in a cave at Bruniquel in southern France has been dated to at least 47,600 years ago, before modern humans reached western Europe. It proves Neandertals were able to use fire for illumination. Earlier evidence showed only that they used fire in simple hearths. The bone came from a 13- by 16-foot structure made of stalactite and stalagmite fragments. Built by Neandertals, its purpose is unknown.
Excerpt:
The Neanderthals began to be displaced around 45,000 years ago by modern humans (Homo sapiens), as the Cro-Magnon people appeared in Europe. Despite this, populations of Neanderthals held on for thousands of years in regional pockets such as modern-day Croatia and the Iberian and Crimean peninsulas.
Excerpted table:
Neanderthal physical traits
Sub-cranial
- Considerably more robust
- Large round finger tips
- Barrel-shaped rib cage
- Large kneecaps
- Long collar bones
- Short, bowed shoulder blades
- Thick, bowed shaft of the thigh bones
- Short shinbones and calf bones
- Long, gracile pelvic pubis (superior pubic ramus)
- Suprainiac fossa, a groove above the inion
- Occipital bun, a protuberance of the occipital bone that looks like a hair knot
- Projecting mid-face
- Low, flat, elongated skull
- A flat basic cranium
- Supraorbital torus, a prominent, trabecular (spongy) browridge
- 1200-1750 cm³ skull capacity (10% greater than modern human average)
- Lack of a protruding chin (mental protuberance; although later specimens possess a slight protuberance)
- Crest on the mastoid process behind the ear opening
- No groove on canine teeth
- A retromolar space posterior to the third molar
- Bony projections on the sides of the nasal opening
- Distinctive shape of the bony labyrinth in the ear
- Larger mental foramen in mandible for facial blood supply A broad, projecting nose
Excerpt: It has also been suggested that much of the brutish appearance of the Neandertals, such as their eyebrow ridges, is due to the enormous chewing stress on the skull imposed by their powerful jaws. And this was due to the common eating of tough food. They are now placed in the same species as modern-day humans, being put into the sub-species Homo sapiens neanderthalensis (with us being in the sub-species Homo sapiens sapiens). However, the bony differences between them and modern people may be the result of trivial genetic differences. Similarly, people of modern ‘races’ today look more different than they are at the genetic level. Some ‘Neandertal’ bony characteristics are found in some Europeans today.
Excerpts:
Professor Ralph Holloway, from Columbia University, New York, is an expert on ancient brains. His assessment of the Neanderthal skull was startling. It was 20% larger than the average size of a modern human's brain, and anatomically identical. He could tell that this Neanderthal was right-handed and that that the areas of brain responsible for complex thought were just as advanced as ours. He should have had the ability to think like us….
The Neanderthal vocal tract seems to have been shorter and wider than a modern male human's, closer to that found today in modern human females. It's possible, then, that Neanderthal males had higher pitched voices than we might have expected. Together with a big chest, mouth, and huge nasal cavity, a big, harsh, high, sound might have resulted. But, crucially, the anatomy of the vocal tract is close enough to that of modern humans to indicate that anatomically there was no reason why Neanderthal could not have produced the complex range of sounds needed for speech….
Analysing the inner ear of a Neanderthal, Professor Fred Spoor, from UCL, has discovered clues to Neanderthal's agility. The semi-circular canals of the inner ear provide sense of balance, and by studying a range of animals, he has found a high correlation between the size of the canals and agility. Throughout human evolution, the canals seem to have increased in size as our agility has increased. But Neanderthals have smaller canals than both modern humans and even earlier ancestors. This suggests they were less agile.
Excerpts:
The Tianyuan remains display diagnostic features of modern H. sapiens. But co-author Erik Trinkaus and his colleagues argue, controversially, that the bones also display features characteristic of earlier human species, such as relatively large front teeth….
An earlier study by Professor Trinkaus shows that human small toes became weaker during the stage of prehistory known as the Upper Palaeolithic, and that this can probably be attributed to the adoption of sturdy shoes. The invention of rugged shoes reduced humans' reliance on strong, flexile toes to grip and balance (“Ancient human unearthed in China,” BBC, 2 Apr 2007).
Excerpt:
Our understanding of early hominids was led astray at the beginning of the 20th century as a result of the discovery by Charles Dawson in 1912 of a fossil skull in England that became known as the Piltdown man. It had a large brain case similar to modern humans but an ape-like jaw. This fit with the popular but incorrect assumption that our early ancestors would have ape-like bodies and human-like brains. The discovery of australopithecines in South Africa beginning in 1924 showed that the early hominids were actually just the reverse―they had almost human-like bodies below the neck but brains that were very little changed in size from those of apes. It was not until the early 1950's that the Piltdown man skull was exposed for what it really was, a clever fraud. This realization came as a result of close examination by independent researchers and fluorine analysis dating.
Excerpt:
For more than three decades, Lucy and her kind were considered the ancient forbears of the human race, among the first to walk upright. But Tel Aviv University researchers revealed in a journal article published yesterday that Australopithecus afarensis, which walked nearly upright but had a brain resembling that of a chimpanzee, was nothing but a cousin of those forbears and belongs to a different branch of the human family - one that became extinct millions of years ago. The findings mean that researchers now recognize an evolutionary gap of more than 1 million years during which no fossils have been found that could be considered the ancient ancestors of humankind (Ilani, Ofri. “Lucy is mankind’s cousin, not mother,” haaretz.com, 18 Apr 2007).
Excerpt:
The shape of the ramus is species-specific among certain groups of primates. The human ramus is similar to that of a chimp and orangutan, as well as that of several other primates, while that of Au. afarensis is similar to gorillas.…Three Israeli scientists have reported in the most recent issue of the Proceedings of the National Academy of Science1 that Au. afarensis may not be our ancestor at all. It all hinges on the jaw of these creatures (pardon the pun). Alas, Au. afarensis has a lower jaw bone (mandible) that closely resembles that of a gorilla—not that of a human or even a chimp. The scientists conclude that this “cast[s] doubt on the role of Au. afarensis as a modern human ancestor.”
Excerpt:
Those salamanders that spend all or part of their lives on land tend to be slight, with small heads, slender bodies, and a sprawling gait that comes from moving the two legs that are diagonally opposite one another at the same time. Aquatic salamanders, such as the amphiuma, are usually larger, and they often have reduced limbs. Some aquatic salamanders, such as the greater siren, have no hind legs at all. The front limbs of most species end in four fingers, and the rear limbs typically end in five toes. Like other amphibians, salamanders do not have claws.
Excerpt:
Amphiuma, eel-like aquatic salamander of the southeastern United States, also called the two-toed amphiuma, congo eel, conger eel, blind eel, ditch...
Excerpt:
Their skulls are flat and wide….Eyesight can be well developed in all but cave salamanders that have only vestigial eyes or are blind. They also have a good sense of smell, and those that live primarily in water have a well-developed “lateral line system” method of sensing the presence of other creatures in water.
Excerpt:
Siren (animal), common name for members of a family of eel-like salamanders. These tailed amphibians have no rear legs, small front legs, and...
Excerpt:
Features:
- Size: 3 1/4-5 3/8 inches
- Color: White to pale pink with translucent skin
- Other:
o Large head with flattened snout
o Reduced, vestigial eyes beneath the surface of the skin
o Bright red external gills
o Thin, elongate limbs
o Finned tail tapering at tip
o Four toes on front feet, five on hind feet
o Twelve costal grooves…
Excerpt:
Two Texas salamanders, each inhabiting separate cave systems, probably resemble past stages of the highly adapted Eurycea rathbuni. Compared with their surface relative, they show progressively greater loss of pigment, degeneration of eyes, elongation of legs, slimming of the body, and flattening of the snout. Possibly, at some time in the future both species also will develop the grotesque modifications of Eurycea rathbuni.
Excerpt:
Baryonyx was an unusual theropod with huge 1-foot (30.5-cm) long claws on its hands, and long, narrow, crocodile-like jaws with 96 small, serrated teeth (this is 1.5 times the number of teeth that most other theropods had). It had a small crest on its snout. Baryonyx had a long, straight neck (unlike other theropods, who had s-shaped necks) and a long tail. Its low-slung body was supported by 2 large rear legs and 2 slightly smaller arms. It was a carnivorous dinosaur from the early Cretaceous period, about 125 million years ago. This predator was about 32 feet (9.5 m) long, weighing perhaps over 2 tons….
Baryonyx was a carnivore, a meat eater with huge claws and many small, sharp teeth in powerful, crocodile-like jaws. It had 64 teeth in the lower jaw but only 32 teeth in the upper jaw (the upper teeth were larger than the lower teeth).
Baryonyx was a large predator that ate fish. A fossilized Baryonyx was found with a fossilized meal in its stomach; this stomach contained fish scales, fish bones, and some partially digested bones of a young Iguanodon. So far, Baryonyx is the only known dinosaur that ate fish. It may have waded in rivers and shallow seas to catch fish (just as some modern-day bears do)….
Baryonyx may have walked on two or four muscular legs. Although the front legs shorter than the rear legs, they were not that much shorter.
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The CT scans revealed something scientists had never before been able to see in such detail. Protruding from the delicate network of brain tissue was the optic nerve. This nerve was responsible for relaying information from the eyes to the visual centres in the brain. And it was big enough to carry a lot of information. The scan seemed to confirm T. rex did indeed have a key attribute to a skilled predator. It would have been able to seek out its prey at a distance, and destroy it with the accuracy of an assassin.
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Though barely detectable, proteins of collagen 1, the main organic component of bone, were separated and examined. Fragments, or peptides, of the protein were pieced together into strands of the seven sequences. Three of these reacted with antibodies to chicken collagen. Two others appeared possibly related to living creatures, a frog and a newt (Wilford, John Noble. “Scientists Retrieve Proteins From Dinosaur Bone,” nytimes.com, 12 Apr 2007).
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Moreover, while some of the peptide fragments showed sequence matches to chickens, others matched frog, or newt, or even fish and mice.
T-Rex Has DNA Similar to Frog, Newt, and Chicken
Squishosaur scepticism squashed: Tests confirm proteins found in T. rex bones, by Shaun Doyle, 20 Apr 2007
A protein sequence from T. rex was mapped and compared to other living creatures, such as a frog, a newt and a chicken. The results showed a 58% similarity with the chicken and 51% with the newt and frog…. the original paper documents a sequence similarity in the T. rex and chicken proteins of only 58% compared to 81% similarity between humans and frogs
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T-Rex DNA very similar to human DNA--within the realm of human variability observed today
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