Soft tissue in fossils vs fossilized soft tissue

—A clarification

Today’s article started life as an internal memo sent to all CMI staff writers, concerning reports in the secular literature of ‘soft tissue preservation’ in fossils. It is a reminder that terms like ‘fossilized soft tissue’ or ‘soft tissue preserved’ can mean two different things. Both are encouraging to the creation/Flood model, but for different reasons. Unfortunately, scientific reports do not always make it clear which is being referred to. However, the distinctions matter, and it is important that biblical creationist writers leave their readers in no doubt about which of these two different situations is being referred to. We commend this article (a mildly edited version of the memo) to our readers.

by CMI Editors

Image: Dr Mary SchweitzerCells and connective tissue can be clearly seen.
Cells and connective tissue can be clearly seen.

When a scientific report or an article commentary refers to soft tissue being preserved in a fossil, this could refer to one of two largely separate things (A or B below):

  1.  The ‘Mary Schweitzer-type’ discoveries, where some of the actual (original) soft tissue is still present, with such things as actual softness/stretchiness once the mineral matrix is dissolved, intact cells, and importantly, identifiable intact proteins such as collagen, osteocalcin, DNA. (The fact that they can be identified means that a good portion of the amino acid sequence making up the protein has not ‘fallen apart’.) See Dinosaur soft tissue and protein—even more confirmation!

In fact, the majority of reports that refer to soft tissue being preserved, even where they talk of it being ‘amazing’ and/or ‘rare’, are in a different category, namely they simply mean to tell us that:

  1.  The shape/outline/features of what was soft tissue can be readily seen. For example, amazement is expressed that a fossil recognizably shows the structural features of something like the brain, or the texture of the skin, often in great detail. But the actual soft tissue is no longer present.

Wording like soft tissue being ‘preserved’ or ‘present’, or ‘fossilized soft tissue’ usually does not mean to say that components of the actual original tissue were present. It generally means that components that were once soft tissue are ‘preserved as stone’. This is through the originally soft tissues being permineralized (or totally replaced by mineral), or an impression left in soft sediment which then hardened. Alternatively, it may be a ‘cast’ of such an impression, including possibly a 3D cast of the whole organ, as the cavity left behind after it decayed was replaced/filled with mineral.

Consider: articles about fossils in general may refer to the bones of a skeleton being ‘preserved’ without meaning thereby that they are claiming the original bone matrix and proteins are still present. Equally, reports of ‘amazing soft tissue preservation’ are usually just referring to soft tissues preserved in stone. They are saying that, instead of the common situation where only the bones of a creature were preserved (as stone, in effect), much less commonly the soft tissue is also preserved (again, as stone in effect). I.e. ‘preserved’ in these instances does not mean ’preserved as intact or original soft tissue’.

Note that in the case of B, it is referring to actual appearances—e.g., something that looks like the shape of a part of the brain, or the liver, or skin texture. So we have a good idea from the petrified body parts what their shape would have been like in life. In contrast, A-type discoveries may not even look like part of a soft tissue organ—e.g., the original Schweitzer-type discoveries were in a piece of leg bone from an otherwise unremarkable T. rex fossil.

Of course, it is possible to have a combination of A and B. Thus, instances of B-type reports may have yet-undetected actual proteins in the fossil. They may not have tested for actual soft tissue, even though it is becoming common knowledge that such preservation occurs, and finds receive favourable publicity.

In fact, therefore, if any of the many ‘soft tissue preserved in fossil’ reports we see nowadays were explicitly referring to an intact piece of actual soft tissue, the report would likely trumpet that loudly, as the find would be even more sensational. It would/should therefore be reasonably obvious from the original paper which type of preservation is involved.

More terminology confusion

The scientific literature on fossils, particularly dinosaurs, has started to refer to some type B specimens as displaying ‘mummified’ tissue (even calling the specimen as a whole a ‘dinosaur mummy’)—even though the tissue in question is preserved as stone in the usual type B way.1

This is unfortunate, as mummified would normally be meant to imply that the original tissue is still present, only preserved through, e.g., desiccation (drying).

It seems to be an attempt to explain the beautiful preservation, which even secular researchers usually admit requires rapid burial, by suggesting that it was mummified before being (slowly) buried and fossilized.

Relevance to creation and the Flood

These two categories, A and B, actually involve two separate (though related) creation arguments and evidences.

  • Type B reports are primarily evidence for rapid burial.

    Of course, even where there are no preserved soft tissue features, a bonebed full of the largely articulated2 fossil skeletons of large dinosaurs is also evidence for rapid processes. This is because, if it took years and years to fossilize the skeleton, it would at the least be disarticulated (i.e., the bones would fall away from each other). The preservation of soft tissue features is additional ‘icing on the cake’ evidence for rapid burial. However, it is of course true that there may be chemical and other reasons why some Flood-burial environments are more likely to preserve soft tissue, rather than just the bones, or fine details; like the famous Solnhofen limestone (see this example). In other words, where, for instance, the details of the appearance of the skin were preserved in a dinosaur fossil, that does not necessarily mean they were buried more rapidly than the dinosaurs in a particular graveyard of fossil skeletons. But it still, obviously, speaks of rapid burial or else those preserved soft tissue features would decay before being fossilized. Note that type B soft tissue preservation is not in and of itself an argument against millions of years, other than in the sense that rapid burial gives support to Flood geology in general, and a global Flood washes away the ‘millions of years’.

  • Type A reports are primarily evidence against the fossils being tens-of-millions of years old

    Regardless of the mechanism of burial, these substances just should not be there anymore. Evidence of rapid burial in addition would be largely incidental to this argument, in that if the evolutionist/long-ager were claiming that they were slowly buried, it would make it even harder to explain the undecayed tissues.

In summary

Reports of soft tissue preservation in fossils feature regularly in the scientific literature. Soft tissue preservation can mean one of two different things. Both of them are relevant and important to the creation/evolution issue, and both are encouraging to biblical creationists.

However, articles about such discoveries should be written in such a way that readers are not likely to conflate the two issues. For one thing, a failure to bring clarity could potentially weaken a person’s witness to an informed person familiar with the original report.

Published: 25 October 2022

References and notes

  1. Buehler, J., Dinosaur ‘mummies’ may not be rare flukes after all, Sciencenews.org, 13 Oct 2022. Return to text.
  2. The bones are in the same relationship to each other as in life, as if they were still connected by the joint ligaments. If ligaments have had the chance to decay, the bones readily ‘fall apart’ and lose that relationship. This is commonly seen in the skeletons of dead animals, whether from roadkill events or natural causes. Return to text.