Evolving a Feather By Shuffling Parts

Science

(SpareHeadOne) #21

Do you think the common ancestor of known dinosaur fossils had feathers/proto feathers?


(SpareHeadOne) #22

“”“Here we report a new ornithischian dinosaur, Kulindadromeus zabaikalicus, with diverse epidermal appendages, including grouped filaments that we interpret as avianlike feathers. This suggests that all Dinosauria could have had feathers…”""

“”“Phylogenetic analysis (figs. S10 and S11) (15) recovers Kulindadromeus as a basal member of Neornithischia [all genasaurians more closely related to Parasaurolophus walkeri than to Ankylosaurus magniventris or Stegosaurus stenops (16)]”""

“”“The presence of both simple and compound filamentous structures in Kulindadromeus (Fig. 4) supports the hypothesis that the integumentary structures in Ornithischia, already described in Psittacosaurus (12) and Tianyulong (13), could be homologous to the “protofeathers” in non-avian theropods. In any case, it indicates that those protofeather-like structures were probably widespread in Dinosauria, possibly even in the earliest members of the clade.”""

“”“Both paleontological and genetic evidence, however, suggests that the pedal scales of ornithuromorph birdsare secondarily derived from feathers. In avialan evolution, leg feathers were reduced gradually in a distal-to-proximal direction, with eventual loss of the distal feathers and appearance of pedal scales in ornithuromorphs (25). Further, evo-devo experiments (26, 27) show that feathers in extant birds are the default fate of the avian epidermis, and that the formation of avian scales requires the inhibition of feather development. The local formation of scales requires the inhibition of epidermal outgrowth, regulated by the sonic hedgehog pathway; this inhibition is partially lost in the case of breeds with feathered feet (27). Therefore, it is possible that the extensively scaled distal hindlimbs in Kulindadromeus might be explained by similar local and partial inhibition in the development of featherlike structures. The preservation of featherlike structures and scales in the basal neornithischian Kulindadromeus, and their similarity to structures that are present in diverse theropods and ornithuromorph birds, thus strongly suggest that deep homology mechanisms (28) explain the complex distribution of skin appendages within dinosaurs (23).”""


(John Harshman) #23

It’s possible; the evidence is ambiguous. It’s also possible that the common ancestor of dinosaurs and pterosaurs had protofeathers.


(SpareHeadOne) #24

Thankyou.
So with birds, feathers come from/with skin, and scales come from feathers. Does that sound correct to you?
Do you think it’s reasonable that the same could be said for dino’s?


(George) #25

@SpareHeadOne

I would find it most unreasonable to think that the same did not apply to dinos!

Everything about the anatomy of some dinosaurs and imputed behavior fits perfectly well with birds. What else would birds be if not small, specialized dinos?


(SpareHeadOne) #26

Great thanks.
So in evolutionary theory, what were the first features of the ancestors of dinosaurs?
Did they get skin, then feathers, then scales?


(George) #27

@SpareHeadOne

Well… could you be pulling my leg? Let’s assume NO!

Dinosaurs, like most tetrapods arrive with SKIN, without a doubt.

As for SCALES, this might be a requirement for all reptiles, yes? I’m not quite sure on that point.
Certainly amphibeans can be WITHOUT scales… like Frogs. But do we know of any amphibeans who develop scales? An important side note: Mammals can have true scales! Voila! The Pangolin Anteater!

The “proto-structures” found in reptile skin to provide scales can be diverted to creating something OTHER than scales… they can be diverted to create things like feathers… as well as feathers.

Enjoy the cladogram below:

Gustavo M. E. M. Prado​, Luiz Eduardo Anelli, Guilherme Raffaelli Romero - New occurrences of fossilized feathers: systematics, taphonomy, and paleoecology of the Santana Formation of the Araripe Basin (Cretaceous), NE, Brazil [PeerJ Preprints]

Simplified cladogram of Dinosauria with the distribution of feathers according to the fossil record. Despite its more ancient origin, it was only in maniraptoriformes that modern-type feathers (pennaceous feathers) have arisen (Based in Xu & Guo, 2009; Clarke, 2013; Godefroit et al., 2013; Han et al., 2014; Koshchowitz et al., 2014).


(SpareHeadOne) #28

I’m trying to run the scenario as it stands.
Fish had scales which I assumed was where reptiles scales came from which in turn was where I assumed Dino and bird scales came from. Which in turn was where I thought bird and Dino feathers came from. But now I find that feathers don’t come from scales and I find that in birds, scales come from feathers. And now it is postulated that Dino scales come from feathers too.
I’ve read that crocodiles scale genes can be tweaked to make the scales more like a feather. Now I don’t know if it’s because the scale genes are “blunted” feather genes or if they are genes that were evolving toward becoming feather genes.
Can you cure me?


(John Harshman) #29

No.

No.


(John Harshman) #30

That’s your first problem.

Not true. You have misunderstood.


(SpareHeadOne) #31

Please tell me how it is. Cheers


(John Harshman) #32

Too much work; your confusion is too deep and too dearly held.


(George) #33

@SpareHeadOne

Oh for goodness sake… do some READING!

I recommend this as your starter:


(Robert Byers) #34

I see no diversity at all. its a one model fits all. I mean if this ‘feather thing’ can be created then it could of/should of had a glorious diversity in manisfestations. Yet still a feather kind.
In fact the feathers are so stuck in thier kind they draw conclusions from them based on fossils from a hundred million yers ago THEY SAY.
they are teaching a lack of diversity in a feathers style.
Just a off broadway point i notice in evolutionism. for all the glory attributed to mutations they do very little in diversity despite time being on thier side.


(Robert Byers) #35

Yes they are good insulation. Mothers enclose the kids during sleep time with their wings.
If evolution was creating insulation why would it do it this way? Why then it could be turned to good use to fly in the sky? With mutations evolutionists are alchemists. They can do anything!!
Yet in doing anything it makes all of it just impribable ;ines of reasoning.
Evoliutionism is about mutationism and its just a fairy tale.
Its ending bin our time.


(SpareHeadOne) #36

I don’t hold any ideas on this stuff.
Where do I look to find answers that line up with yours?


(George) #37

@SpareHeadOne

@John_Harshman is a scientist… you should probably read some science:


(SpareHeadOne) #38

I’m asking because he is a scientist. I was asking the right man for the question.
I laid out my ignorance, which is a somewhat humbling thing to do, but I laid it out so that it could be easily corrected. Instead I was met with guesses about my motives and told that I am too messed up in the brain. (Who the hell presses like on that kind of pointless garbage).
I won’t be asking anymore questions and I will take your less than kind advice and just read.


(George) #39

@spareheadone

Less than kind advice? Shucks, I’m saving you lots of grief. As to
very good question: “(Who the hell presses like on that kind of
pointless garbage).”, I have asked that kind of question a couple of
times myself. That’s why I thought I was doing you a favor by giving
you an article to read … instead of trying to squeeze a drop of warm
sweetness out of a husk.

Don’t worry … I won’t take your rush to judgment on the nature of my
advice personally. You’ll get a feel for the terrain over time.


(SpareHeadOne) #40

Sorry I recognise the kindness in your abruptness. Thankyou very much for the articles and the clad.
Now I will go back to reading.