"Soft tissue" found in dinosaur bones doesn't refer to fresh, pliable flesh; rather, it describes the discovery of fragments of collagen and other proteins preserved within the mineralized matrix that has replaced the original bone. This remarkable preservation of normally degradable material offers valuable insights into dinosaur biology.
What is Being Found?
Instead of intact organs, what scientists are finding includes:
- Collagen fragments: Collagen is a fibrous protein and a major component of bone, tendons, and ligaments. It's surprisingly resilient and can, under specific circumstances, resist complete decay.
- Other proteins: In addition to collagen, other proteins and even fragments of DNA have been reported. While the authenticity and source of some of these finds are debated, the preservation of complex organic molecules is still noteworthy.
How is it Possible?
The preservation of these biomolecules requires specific and unusual conditions. Here's a breakdown of factors that can contribute:
- Rapid Burial: Quick burial after death limits exposure to scavengers and surface elements.
- Specific Geochemical Environment: Certain minerals and environmental conditions can inhibit bacterial decay and promote preservation. The presence of iron, for example, has been suggested to play a role in cross-linking and stabilizing the proteins.
- Mineralization: The process of fossilization involves minerals replacing the original bone. This can also encapsulate and protect some of the remaining organic material. It is embedded in this mineral matrix where the "soft tissue" is found.
What is it NOT?
It's crucial to understand what this discovery isn't:
- Not Dinosaur DNA Ready to be Cloned: The DNA fragments, if present, are typically too degraded to allow for anything like cloning.
- Not Soft, Flexible Tissue Like We See in Living Animals: The proteins are encased in rock and not easily separated as a functional tissue.
Significance of the Discoveries
Despite being fragmentary, the discovery of these proteins and other biomolecules has significant implications:
- Molecular Phylogeny: Comparing the amino acid sequences of preserved proteins can help determine the evolutionary relationships between dinosaurs and other animals.
- Understanding Fossilization Processes: The finds provide new insights into the processes of fossilization and what conditions are necessary to preserve organic material over millions of years.
- Confirming Dinosaur Biology: Provides evidence to support what we already theorize about dinosaur biology.
In summary, the "soft tissue" in dinosaur bones represents the preserved remnants of proteins and other biomolecules within the fossilized bone matrix, offering a rare glimpse into dinosaur biology and fossilization processes. It's not about finding fresh, unaltered flesh but rather understanding how specific conditions can allow for the survival of normally degradable organic materials over vast periods of time.
