[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Sinosauropteryx

Having taken a look at the illustrations, this thing does not look
"bald" to me at all. There are some fairly nice patches of
proto-feathers along the tail

Better yet. Lingham-Soliar et al. notice this patchy but regular distribution and interpret it as a "scalloped frill" (Fig. 2f). But look at the vertebrae (Fig. 2d). Between the feather patches, they are lighter in color and have a smoother surface. Looks to me like the tail is not in the plane of the slab, but undulates with respect to it; in the feather patches the slab is split through the vertebrae, so we're looking at their compressed interior, while between the patches it is split between the vertebrae and the rock.

Then behold Fig. 4. It shows several layers of the prepared slab.
At the bottom (also the bottom of the figure) we have just rock.
Above that is a grayish layer with a lot of parallel lines, the one with the yellow arrows, the red arrows, and "1". Obviously, I agree: this layer doesn't look like feathers at all. Lingham-Soliar is an expert on collagen, so if he says this looks like collagen, I see little reason to consider consider it feathers when it doesn't look like feathers. It's a bit far away from the vertebrae, but the animal is squished flat, so maybe we are looking at the dermis or hypodermis/subcutis of the bottom of the tail, or perhaps even at the M. caudifemoralis longus (which of course is not collagen, but still should preserve as parallel striations if at all, and is ventral of the transverse processes).
Above that layer, however, there is a layer with lots of brownish stuff, the one with "(b)", "2", and "3" in it in the "close-up". Lingham-Soliar et al. hardly mention it, even though it makes up most of the picture (the preparator has dug through it to expose the chevrons and more fully expose the vertebrae; the top of the figure shows the same layer again), and don't seem to notice it's a different layer than the one with the grayish stuff. Here, too, we have striations, but they are much shorter and much more irregular. Some, at least, look reasonably similar to feathers even at the resolution of the picture, and bird feathers in those sediments also tend to preserve in brown to black. This layer is where I'd like to see some microscopy.
Above we have rock again, covering most of two chevrons.

Like last time, the supposedly close-up photos are DESCREENED. Looking at them hurts because they are so blurry, and the arrows point somewhere into the mist.

The beaded appearance looks like it's simply the rock. The rock is not perfectly smooth, and a feather preserved on a slab has next to zero thickness. The descreening of Fig. 3a, b, and d does not help at all.

Are we now back to that
absurd-looking aquatic compsognathid again?

But nooooo. Now the collagen is for stiffening the tail (they have, after all, never heard of terms like "transition point" and therefore believe that tails must droop unless stiffened the dromaeosaurid way) and for making the skin tougher (oh, how poor *Sinosauropteryx* was for lacking osteoderms; notice how all terrestrial mammals except armadillos, pangolins, and those odd African shrews have long, long ago died out).

Not the slightest mention of the preserved scales of champsosaurs, lizards, and *Psittacosaurus*, of preserved mammal-sensu-lato hair, or of the real preserved tail fins of larval/neotenic salamanders from the same formation.

And of course, *Juravenator* is a compsognathid, of course it is entirely unthinkable that anything might have feathers on only part of its body (when scales are preserved anywhere, the absence of any kind of preserved integument on the rest of the body proves the absence of feathers), and all coelurosaurs must have the same integument because, after all, they are all coelurosaurs.

Best hypercorrectivism I've seen in a long time: "rigour mortis".