http://www.pnas.org/content/104/suppl.1/8582.full
Adaptable robust processes can support nonlethal phenotypic variation in other processes, a situation called “accommodation” by West-Eberhard (14). A specific example is the evolution of the tetrapod [pterosaur] forelimb to a bird or bat wing. Not only did the length and thickness of bones change, but also the associated musculature, nerve connections, and vasculature. Did many regulatory changes occur in parallel, coordinated by selection, to achieve the coevolution of all these tissues in the limb evolving to a wing? The answer comes from studies of limb development showing that muscle, nerve, and vascular founder cells originate in the embryonic trunk and migrate into the developing limb bud, which initially contains only bone and dermis precursors. Muscle precursors are adaptable; they receive signals from developing dermis and bone (17) and take positions relative to them, wherever they are. Then, as noted previously, axons in large numbers extend into the bud from the nerve cord; some fortuitously contact muscle targets and are stabilized, and the rest shrink back. Finally, vascular progenitors enter. Wherever limb cells are hypoxic, they secrete signals that trigger nearby blood vessels to grow into their vicinity (18).
A specific example is the evolution of the tetrapod [pterosaur] forelimb to a bird or bat wing.
ReplyDeleteThe pterosaur makes a very sly appearance here, inserted by Dr Pterosaur.
A specific example is the evolution of the tetrapod forelimb to a pterosuar, bird or bat wing.
This sentence would make some sense.
There is a convention that [ ] square brackets indicates something purposefully added.
ReplyDeleteBy explicitly using the square brackets it is intended to highlight to the reader that it has been added on purpose.
It is not "sly".
If I had put it in ( ) rounded brackets, that would have been sly since it would have looked like it was part of the original.
Anonymous are you familiar with the [ ] square bracket convention?
Dr. Pterosaur is not addressing the comment.
ReplyDeleteA specific example is the evolution of the tetrapod forelimb to a [pterosaur,] bird or bat wing. as a sentence would make sense.
A specific example is the evolution of the tetrapod [pterosaur] forelimb to a bird or bat wing. does not make any sense.
Anonymous are you familiar with the [ ] square bracket convention?
ReplyDeleteLet's settle this aspect before we move on.
The reason this square bracket [ ] issue is important is because I am working with articles that do not take the point of view I am proposing.
ReplyDeleteBy using the square bracket convention I am explicitly and transparently indicating that I am adding something. The reader can see that.
I am not hiding anything or attempting to fool anyone.