"Non Theropod".
Anchiornis huxleyi + "nontheropod sacral anatomy" explained. (Source)
I like what Feduccia says.
"... a large suite of avian characters are present, especially in Anchiornis, we must remain open to the view that they represent a primitive group of early avians."
... back to the basal archosaurs. No room for "intermediate fossils" between the basal archosaur and birds. No room for transitions. If Feduccia thinks there's any "open mindedness" among the dinosaur-to-bird crowd, he's the one who's mistaken.
Feduccia's book on the origins of the feathered feet, could not have been terrestrial as formally claimed...
Feathered and webbed feet explanation.
That... lead me to a verrrry interesting find. Why those little feathery feet. The dino-bird crowd think "terrestrial dinosaur". But that's not what the Feduccia's colleague theorizes. (See below).
Feduccia points out that "it could not have been terrestrial" -- so what was it, a snowshoeing bird in the Arctic? Those feathered feet do not equate to "terrestrial tetrapod dinosaur".
Here's three science papers on the "Ornithuromorph" birds.
"...thus expand our knowledge of Early Cretaceous specializations within the aquatic niche..."
"...As more ornithuromorph taxa are described, it is becoming increasingly clear that a majority of species have aquatic specializations..."
"...especially amphibious or aquatic habitat preferences in early ornithuromorphs."
T. REX NEED NOT APPLY.
Paleoecology
Elongate hindlimbs in birds are commonly associated with aquatic ‘shorebird’/littoral ecological niches (Zeffer et al., 2003). The presence of a dorsal supracondylar structure in Longicrusavis, together with the proportions of the legs (elongate tibiotarsus) and feet (elongate proximal phalanges, short hallux), suggests that hongshanornithids occupied such a niche. Wading ‘shorebird’ taxa are known from the Late Cretaceous; the enantiornithine Lectavis bretincola from the South American Lecho Formation is suggested to have filled this niche based on the long and gracile nature of its tarsometatarsus (Chiappe, 1993). Ostensible charadriiform taxa, such as Cimolopteryx maxima, Graculavus velox,and Telmatornis priscus,have been reported mostly from the Late Cretaceous of North America (Hope, 2002); how ever, these taxa are fragmentary and their referral to Charadriiformes is questionable. The Early Cretaceous record of aquatic taxa is limited to the exceptional Gansus yumenensis and inconclusive trackways from Asia and Europe (Lockley et al., 1992; Fuentes Vidarte, 1996; You et al., 2006). The hongshanornithids thus expand our knowledge of Early Cretaceous specializations within the aquatic niche. The Hongshanornithidae are known from lakes located relatively close to the coast, in contrast to the younger more phylogenetically derived Gansus, which is known from inland deposits in northern Gansu Province, China. As more ornithuromorph taxa are described, it is becoming increasingly clear that a majority of species have aquatic specializations such as elongate hindlimbs and pedal digits and proximally projecting cnemial crests on the tibiotarsus (Yanornis, Gansus, Hongshanornis).
Longicrusavis also possesses specializations for a littoral environment,and together with Hongshanornis,reveals an early diversification of wading birds.
(Source)
"05-CM-021 would provide additional phylogenetic and eco-morphological information regarding the early evolution and diversification of Ornithuromorpha, and potentially the origins of Ornithurae. For instance, an important aspect of the paleobiology of Gansus is its presumed aquatic or semi-aquatic lifestyle, which has been inferred from its prominent, proximally-projecting cnemial crest on the tibiotarsus, proximal position of the metatarsal II trochlea, and elongate, webbed pedal digits (You et al. 2006; Hinic-Frlog 2007). Coupled with the phylogenetic position of Gansus as an advanced non-ornithurine ornithuromorph or basal ornithurine,this was considered to support the hypothesis that Cretaceous ornithuromorphs may have been largely aquatic in habits, and that neornithines may have originated in water-based niches (You et al. 2006). Whether or not the taxon represented by FRDC-05-CM-021 possessed similar aquatic adaptations can only be determined by the discovery of more complete specimens, because no sternal or furcular characters have yet been determined to be indicative of an aquatic ecology."
(Source)
Xing Xu Ph.D.:
"...Based on these discoveries, we propose that birds were primitively four-winged, with the hind limbs contributing to aerial locomotion. The separation of the forelimbs and the hind limbs into distinct locomotor modules in later birds, which led to reduction of the leg feathers and outright loss of the pedal feathers, may have been facilitated by ground, especially amphibious or aquatic habitat preferences in early ornithuromorphs." (Source)
Archeopteryx was around during the Jurassic -- frequently lagoons and semi-aquatic, and long before, there's quite possibly "Protoavis" from the Triassic, presumed to also be of modern bird form. We won't know until more fossils are found that correlate. Meanwhile, these are all just descendents of the AQUATIC ancestor among the basal archosaur, which I say was the Patriarch/Matriarchal Bird ancestor... it may have had similarities with dinosaurs, but it was no dinosaur. It may have had descendents that branched which were "dinosaur like" and may have had feathers, but were no true dinosaur.
"...Several new specimens of the previously enigmatic bird Gansus throw light on the evolution of early ornithuromorph birds. There appear to be the following evolutionary grades and clades recognizable to different degrees of clarity amongst the Mesozoic birds. The primitive radiation of birds appear to have included the very deinonychosaur/Epidendrosaur-like forms such Archaeopteryx, Rahonavis and Jeholornis followed by the emergence of birds with shortened pygostylic tails. Interestingly a pygostyle-like structure appears to have also evolved in the Oviraptorosaur Nomingia. Subsequently the pygostylians spawned two great radiations the enantiornithines and the ornithuromorphs/euornithes which included the modern birds. The enantiornithines spanned a wide ecological niche and were dominant birds throughout the later Mesozoic, however for reasons unclear to us they all became extinct in the great K/T event.
Feduccia, proposed a model that the early ornithuromorphs were aquatic or semi-aquatic– his shore birds. The new fossils of Gansus combined with the phylogeny suggest that many of the early clades of ornithuromorphs, such as Hongshanornis, the Yanornis-Yixianornis-Songlingornis clade, the Hesperornithids, Ichthyornithids and Gansus were all aquatic, whereas only Apsaravis is convincingly terrestrial. One must also revisit the somewhat later Vegavis from Antarctica in light of the aquatic early ornithuromorph hypothesis. Examining the ornithuromorph radiation we note that the most primitive member of this clade Patagopteryx appears to be a terrestrial bird, even secondarily flightless. So together with Apsaravis we have at least 3 major ecological niches amongst the better preserved members of the early ornithuromorph radiation- a flightless land form (which might have repeatedly happened in early avian evolution), a volant desert living form and several aquatic forms with different degrees of aquatic adaptation. When we go to the neornithes, we have the basal-most branch of the ratites, which are largely flightless and clearly all terrestrial cursorial forms. The next most basal branch, which are the earliest branching, neognaths are the Galloanserae. In the latter clade we have the late Cretaceous form Vegavis an aquatic form- the authors of that bird even claim it is nested within Anseriforms or the ducks."
(Source)
More dino-bird mythology to carefully dissect and ignore. Some birds have "feathered feet".... but why?
To snowshoe, they say. But the Cretaceous, when T. Rex roamed is suspect as being very warm :
Paleoclimate
"...In general, the climate of the Cretaceous Period was much warmer than at present, perhaps the warmest on a worldwide basis than at any other time during the Phanerozoic Eon."
(Source)
Now, everyone in the dino-bird camp is trying to explain why T. Rex must have had to have feathered feet too.
Not odd. They don't understand biology, birds or dinosaurs -- and that features "evolve" with purpose. Feathered feet are associated with very cold (even non-terrestrial) -- and that doesn't describe the very warm Cretaceous... also, very terrestrial... T. Rex.
TETRAONIDAE (This natural and fairly homogeneous group belongs to the order Galliformes, and is sometimes regarded as a subfamily within the Phasianidae...toes with scales on the sides adapted to climbing branches and walking on snow, shorter tail and heavier body with duller plumage.)
As shown, these "feathered feet" are used to snow-shoe. (Source)
Plio-Pleistocene climatic oscilations, Holarctic biogeography and speciation in an avian subfamily Sergei V. Drovetski*
Department of Ecology, Evolution and Behavior, University of Minnesota, St Paul, MN, USA
DISCUSSION
Although the estimated dates of Tetraoninae divergences have wide margins (Table 1) they show that the entire proliferation of grouse coincided with the global cooling and climatic oscillations of the Pliocene and Pleistocene. Tetraoninae represent an extraordinary example of rapid response to an environmental change that opened a new niche induced by global climate change. This niche was for large birds capable of wintering on woody foods through the long cold winters.
Paleontological data for the six modern Palearctic Tetraonins (Tyrberg, 1998) and the phylogeny of the entire subfamily (Drovetski, 2002) allowed me to calibrate a molecular clock for the CR sequences of four grouse genera. The mean estimate (SD) is 0.0723 0.0158 substitutions/site/Myr. Dates estimated with this rate should be interpreted cautiously because ML ratio test rejected a uniform evolutionary rate for the grouse CR tree. This rate is slightly higher than the rate calculated for mitochondrial Cytochrome-B gene of Galliforms (5.04%) and Hominids (5.56%) using HKY85 ML divergences (Arbogast & Slowinski, 1998), and the rate calculated for mitochondrial ND2 gene of Galapagos mockingbirds (5.52%) using GRT รพ G model (B.S. Arbogast et al., unpublished data). An application of this rate to the grouse phylogeny showed that they arose in the Pliocene, approximately 6.3 Ma, and their proliferation began c. 3.2 Ma, with the divergence of ancestral Bonasa from the common ancestor of other grouse. These dates are much younger than the 48–28 and 22–17 Ma, respectively, estimated from a single external fossil date calibration that used the divergence between Galliforms and Anseriforms (Dimcheff et al. , 2002). Multiple internal calibration points used in this paper should produce more reliable time estimates than a single point which is twice the age of grouse proliferation.
(Source)
Darwin also bred pigeons which developed feathered feet. It's true, that domestication and cultivation can manipulate genes to change the appearance of the species, in captivity, but once released into the wild -- the species reverts back to its original appearance in the wild.
TAKE A LOOK AT THOSE FEET!!!
What Pigeons Teach Us About Convergent Evolution
"...So why do the same traits keep cropping up in distantly related breeds? The answer lies in human hands. According to the researchers, "In The Origin of Species, Charles Darwin repeatedly calls attention to the striking variation among domestic pigeon breeds - generated by thousands of years of artificial selection on a single species by human breeders.
Because some human breeders thought that feathered pigeon feet were the hottest thing since curly dog fur, they bred selectively for that trait in both the Pomeranian pouter pigeon, whose feet are pictured in the top image, and the distantly related ice pigeon below. And although this form of trait selection is artificial, it's a good example of how evolution works. For example, this independent development of the same trait in multiple different genetic lines, known as convergent evolution, can also occur without human interference. In fact, Charles Darwin used pigeons to describe how selection influences the traits of a species, and as a model for how natural selection can lead to different traits in wild populations.
Despite their careful breeding, when pigeon populations become free-living - either in cities or in the wild - they evolve out of their original appearance."
(Source)
So, if these "feathered feet" are to tell us anything, its that the common ancestor of grouse and pigeon who developed this "feather feet" trait arose in a region where extreme cold prevailed, and this trait has been passed down through time.
If such a bird (with feathered feet) existed during the Cretaceous, and they say it did, then its suspect that it inherited it from a species that came before it, and had survived through an even earlier ice age.
See the "Ice Age" chart from (Source)
Notice on the chart of "Ice Ages" that there is an extreme drop in temperature around 200 Million years ago. Wikipedia has a quick explanation that sounds about right:
"...There is also a "cooler" interval during the Jurassic and early Cretaceous, with evidence of increased sea ice, but the lack of continents at either pole during this interval prevented the formation of continental ice sheets and consequently this is usually not regarded as a full-fledged ice age. In between these cold period, warmer conditions were present and often referred to as climate optima. However, it has been difficult to determine whether these warmer intervals were actually hotter or colder than occurred during the Cretaceous optima."
(Source)
Therefore, the "snow shoes" described on the "Anchiornis huxleyi" creature in the Cretaceous which is described to live around 160-155 million years ago... which had feathered feet ...inherited that trait from an ancestor who evolved during that cold time frame, 200 million years ago.
It seems like "snow shoe" is the word commonly used to describe the type of foot adapted for snow and icey climates.
Polar Bears | Discovery Kids
"...A thick layer of blubber ranging from one or two inches to four and a half inches sits just ... As you can see, a polar bear's paws are essentially snow shoes!"
(Source)
So these birds are not "terrestrial" and though snow is frozen water (aquatic) and they're walking on it... its still not aquatic either. It is "snow shoeing".
"The snowshoe hare (Lepus americanus), also called the varying hare, or snowshoe rabbit, is a species of hare found in North America. It has the name "snowshoe" because of the large size of its hind feet and the marks its tail leaves. The animal's feet prevent it from sinking into the snow when it hops and walks. Its feet also have fur on the soles to protect it from freezing temperatures."
(Source)
On the page, they show a pair of Ptarmigans (relative of grouse).
Penguin Feet: Avoiding Frostbite in the Antarctic
"Penguins of the cold Antarctic and sub-Antarctic also have feathered legs, which are believed to play an important role in conserving heat. In fact, black-footed penguins (Spheniscus demersus) and Humboldt’s penguins (Spheniscus humboldti), which live in warmer areas (Africa’s southwest coast and South America, respectively) have featherless legs.
In addition, the blood vessels running to and from the feet of penguins are organized to facilitate countercurrent heat exchange. Arteries carrying warm blood toward the feet run alongside veins carrying cool blood up from the feet. Some of the heat from the blood in the arteries is transferred to the blood in the veins. Thus, cool blood moving toward the heart is warmed, which is important for maintaining core body temperature. Warm blood moving toward the feet is cooled, which helps penguins keep their feet at temperatures just above freezing. This strategy minimizes the amount of energy needed for keeping their feet warm while also preventing frostbite.
...Other birds have similarly mastered the art of heat conservation and frostbite prevention through countercurrent circulation in their legs and other unique adaptations. Sea gulls and ducks, for example, can stand in icy water with relatively no effect on core body temperature or their feet. The ptarmigan (Lagopus), a year-round resident of the Arctic, has feathers that completely cover its legs and toes. The ptarmigan’s distinct toe feathers are thought to provide some warmth, but perhaps more importantly they provide a snowshoe effect, preventing the bird from sinking into deep snow when foraging."
(Source)
So there is an empirical explanation why "feathered feet" are necessary for survival and serve a biological function... in animals (mammals and birds) in cold regions. WHY the "snowshoe" exists in some creatures, and not merely a random arrangement of anatomical characteristics. There was no need for a T-Rex to have this adaptation, nor his immediate relatives. If they say T. Rex had feathered feet? I'd like them to point out "why." Show me some fossils. Show me some reason. Not just because it "looks cool".
"...because bright red feathered feet are "cool looking"..." isn't legitimate science.
Paleontology today has became a failing religion, all the more I want to pull far away from the bogus madness they're now calling "paleontology".
.. not to mention the obvious:
"...Scientists have weighed Tyrannosaurus rex, finding it may have topped 9 tons..."
I have my doubts that a few feathers on its feet would "...prevent it from sinking into deep snow while foraging".
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