The real complication in reconstructing fossil animals is that there's all the soft stuff that goes on top of the musculoskeletal system. Integument is the great unknown for many fossil animals; its preservation is rare and infrequent, and even when it's preserved, it may be massively distorted or rearranged relative to its position in life. This is important, since the shape and size of the integument can radically change the appearance of the living animal relative to its underlying musculature and skelton.
We are therefore presented with a huge diversity of ‘known unknowns' and ‘unknown unknowns' – the gate is open for all manner of bizarre possibilities as goes the life appearances of fossil animals.
All Yesterdays: Unique and Speculative Views of Dinosaurs and Other Prehistoric Animals
ReplyDeleteby John Conway, C.M. Kosemen and Darren Naish
with skeletal diagrams by Scott Hartman
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Introduction, by Darren Naish
It should be noted that there are some disagreements at the level of reconstructing skeletons and musculature, and that improvements and tweaks are frequently being made. We mostly agree on the positions of muscles, for example, but the sizes of some of the muscles involved are variable in living animals and there is sometimes no reliable way of determining their size in fossil animals.
The real complication in reconstructing fossil animals is that there’s all the soft stuff that goes on top of the musculoskeletal system. Integument is the great unknown for many fossil animals; its preservation is rare and infrequent, and even when it’s preserved, it may be massively distorted or rearranged relative to its position in life. This is important, since the shape and size of the integument can radically change the appearance of the living animal relative to its underlying musculature and skelton. …
If these observations extend across a wide diversity of living animals, would they have done so for extinct ones as well? We have little to go on, but what we know suggests that, yes, integumentary coverings may have effectively obscured much of the underlying anatomy that we’ve worked so hard to reconstruct. Notably, dinosaurs found with soft tissues (namely skin impressions and feathers) are flamboyant. Feathered dinosaurs are not only covered in feathers (with feathering extending from the middle of the snout all the way to the tip of the tail and even down to the ankles or toes), they have especially long, showy feathers growing off their arms and hands, the end parts of their tails, and even (in cases) from their thighs, shins and feet. Fossil mammals with body outlines and fur show a thick halo of tissues surrounding the skeleton, meaning that the skeleton was deeply submerged and effectively invisible in the live animal, as is typically the case in modern species.
We are therefore presented with a huge diversity of ‘known unknowns’ and ‘unknown unknowns’ – the gate is open for all manner of bizarre possibilities as goes the life appearances of fossil animals.
A Book That Will Make You Question Everything You Know About Dinosaurs
ReplyDeleteby Annalee Newitz
http://io9.com/5965389/a-book-that-will-make-you-question-everything-you-know-about-dinosaurs
How did dinosaurs look? The only way any of us know is from looking at images created by paleoartists, people who specialize in imagining extinct creatures by studying their skeletons. The problem is that skeletons only tell us part of the story, revealing little about layers of body fat, skin type, coloration, and behavior. Now, a new book called All Yesterdays: Unique and Speculative Views of Dinosaurs and Other Prehistoric Animals — half science, half-science fiction — offers us a radical new way of looking at dinosaurs, based on contemporary scientific speculation. We have an incredible gallery of the paleoart from the book.
Written by paleoartists C.M. Kosemen and John Conway, with an introduction by renowned paleontologist Darren Naish, All Yesterdays is the kind of wonderful, provocative thought experiment that only exists at the nexus of science and art. The book corrects a lot of misconceptions from famous dinosaur art, such as work by Charles Knight, and then heads off into new speculations based on all the “unknown unknowns” of paleontological reconstruction.