“Where are all the failures?” This question was asked by Joe Bruno, on newsgroup talk.origins. Bruno, although claiming not to be a creationist, had trouble believing that evolution is true. This kind of opposition to evolution is difficult, because it could be an argument of incredulity disguised as a valid question. The argument of incredulity entails confusion between “I can’t see how that works” and “That cannot work”. The person using the argument applies the limits of his understanding as a measuring stick for what is possible.

Regardless of whether Bruno was genuinely interested in evolution or not, the most simple way to respond is to answer the question. His question was specifically about fossils. The theory of evolution, according to Bruno, assumes that there have been many badly adapted organisms in the past. Mutations, after all, can be beneficial or not. So where are the fossils of all those past organisms with non-advantageous traits? For some reason, he specifically mentioned pterosaurs. Perhaps he had difficulty envisioning hordes of lizard-like beings trying in vainly to fly with failed mockeries of wings, only to fall in the mud, die, and be found as fossils by an intrepid paleontologist who descended from more successful creatures. Well Joe: this never happened, and evolution dictates it should not happen.

Definitions of failure

My first question when trying to formulate an answer was: what is a failure? I could mention many fossils of beings who did not survive, but in order to be called, with at least some justification, an evolutionary failure, the organism must have been particularly unsuccessful in producing offspring. Ideally, this was because of the traits the organism possessed; there is little point in declaring an organism a failure when it died of bad luck. A dinosaur living in Yucatan about 65.5 million years ago had zero chance of surviving the meteor that was going to hit it, but this did not make the dinosaur a failure. Because of this, I will consider those organisms failures when their traits make them less suitable for producing a generation after them. The least fit, if you will.

That still doesn’t quite define the ‘failures’ narrowly enough. In fact, most of this blogpost will be about defining the term. Joe Bruno is obviously not a paleontologist, nor a biologist, and he did not think his term through very well. Because of this, some more work on the definition must be done before I can answer exactly what fossils relevant to Joe’s question have been found.

Extent and type

Are failures groups of organisms or individuals? This is quite significant when fossils are concerned. Most individual organisms don’t fossilize, even if the species is a commonly found fossil. Plankton skeletal remains dissolve or are crushed in a creature’s gut. Bones rot away. Shells fall to pieces through erosion. The chances of finding a specific individual with a specific mutation are small. But perhaps Bruno thought that failure can form entire populations, in which case one should be able to find them, perhaps even repeatedly in the same area. But the question remains open: are the failures individuals within a population or do they form an entire population? I call this the failure’s ‘extent’. If you see problems (or even impossibilities) here, bear with me, because they will be addressed.

The second concern is what a failing property is in itself. How do failures operate? Are they radically different with clear disadvantages, or are they organisms with the same basic traits as their peers, but to a lesser degree? Compare two people who want to go long-distance running: one of them is short and heavy-set, with large muscles and big bones. He doesn’t have a lot of talent for running and will probably never be the best. The other person doesn’t have legs. He cannot run in the normal sense. I will distinguish between these traits by calling the second ‘principal failure’, when the failure is a separate quality that prevents the organism from reproducing most effectively, while the first is a ‘suboptimal failure’, which is a quantative failure, where the organism doesn’t have the trait in as high an amount as other organisms. Creationists sometimes assume that the division I am making here is genetic, but I do not assume any particular method of variation being at the basis of these variants. In a genetic sense, they can all be large or small mutations, or simple parent’s recombination. No assumption in that regard is made, I’m purely referring to how a phenotype’s trait functions in its environment.

The scheme of failures

Combining the two divisions, I came up with a scheme that maps the possible failures one might, perhaps, find as fossils. I gave a name to each variation, resulting in this table:

I will now discuss each type.

I. The Failed Experiments:

There is a scene in Alien: resurrection where Ripley (played by Sigourney Weaver) walks into a mad scientist’s laboratory. Throughout the room, there are horrible beings on display. The scientist has been trying to clone Ripley and the alien whose DNA she was carrying, or something like that. Point is, he tried again and again to ‘grow’ creatures until he got it right.

The fossil record should be somewhat like this laboratory. Mad experimenting aside, every once in a while you should find the fossil of an organism that was a bad variant. This organism probably didn’t produce offspring, but that didn’t prevent it from living it’s life till the end. However, these beings are not collected by nature and displayed in one room; such fossils are found between the thousands of others that are, as far as we can see, normal. The mutation may also not be visible in the fossil.

The biggest chance of finding such a fossil is when lots of the same species can be found, for example when looking at many microfossils. That is exactly what happens: every now and then, micropaleontologists come upon strange forms that seem to defy the normal morphologies of the species they’re used to. The microfossil seems to belong to one species, but has developed in an odd way. Usually, they will alert a colleague with some ultra-professional claim in the vein of “Hey, look at this goofy one!” and then go on with counting the species they were counting. One microfossil just isn’t enough to base a thesis on.

Dubois' 'Pithecanthropus' bones

One famous macrofossil displaying a principal failure is actually quite a legendary one: Eugene Dubois’ ‘Pithecanthropus’ had a leg bone with an odd growth on it. Surely the creature it belongedto had trouble walking and was in pain. A clear example of a principal failure, since this was a disadvantageous trait.

II. The Monstrous Horde:
Evolution predicts that a population of principal failures should not exist. After all, if a particular trait makes an organism dominate a population, it is clearly not a failing trait. And if a trait is disadvantageous, it won’t spread in the population.

As we would expect from this, there are no fossil populations of failures. This probably hasn’t stopped paleontologists from claiming to have found them – but the reports themselves proved to be failures. The only example I know is A. E. Trueman’s work on the shells of Gryphaea incurva, which he published in 1922. Trueman thought that, in their evolution, these Jurassic oysters became more curved. Eventually, he claimed, the shells became so curved that they could not open anymore, and the species died out. In 1939, Trueman called this a trend “not in harmony with the environment”, suggesting the creatures were evolving themselves to death. This theory was never accepted, mostly because the shells, as research has shown, actually could open.

So the Monstrous Horde has never been found, as evolution suggests. If Bruno expects it should be found, he can be reassured. It never will.

III. The Lesser Beings:
It is actually quite common to find a fossil with a suboptimal trait. In fact, most organisms are not optimally adapted; we can’t all be Olympic decathlon champions with PhD’s. The trouble, however, is recognizing suboptimal beings in a typical sample of fossils. As the term ‘sample’ suggests, it’s a statistical enterprise.

Once you recognize a certain evolutionary trend, as Trueman thought he did with his shells, you can postulate that the descendants are better adapted than the ancestors. Thus, it can be deduced what the optimal trait is – and what is not. At any point in time during the trend, however, there will be statistical variation in the trend; you can test this by gathering the fossils from the same level and then measuring the trait. Apparently, at that moment in time, there were Lesser Beings who did not have the development in the same amount as the others in the population did.

This approach is somewhat politically incorrect, because Lesser Beings suggests these organisms were overall less fit, which some translate to their worth. It should be noted, however, that a fossil is a lousy measure of a creature’s overall fitness. Lesser Beings are measured by one trait. The best that can be concluded is that they existed in one form or another, it is difficult to point to any one fossil.

Examples of Lesser Beings can be found among larger foraminifera, which show a clear trend called nepionic acceleration. Foraminifera grow as a spiralling series of chambers, and nepionic acceleration entails the gradual fusion of the inner chambers into one large chamber. It can be quantified by counting the number of inner chambers. At one point in time, some individual foraminifera will have more and some less chambers, leading to the conclusion that there are some failures known as Lesser Beings among them.

Opabinia regalis

IV. The Discontinued Products:
The final class of failures can be compared to a commercial product that is conceived, put into production, produced for a few years, and then discontinued for some reason or another after initial success. You might think that the Discontinued Products have the same problem as the Monstrous Horde, i.e. that evolution predicts they should not exist, but I think they might have existed. Discontinued Products are possible if you stretch the definition somewhat: I define them as populations that developed for a certain reason, but that were ultimately doomed to failure. This means that the selection pressure changed during their growth. What made them successful to begin with, couldn’t make them last.

Is there a reason to believe Discontinued Products ever existed? Maybe there is. There have been species that were never able to produce a strong lineage of other species or belonged to such a lineage. Take, for example, some of the Burgess Shale species. A species like Opabinia regalis could be regarded as belonging in this class.

In order for Discontinued Products to have existed, there has to be a kind of evolution on the species level, like the ‘species sorting’ proposed by Niles Eldredge and Stephen Jay Gould. Evolution may tinker on the species level, putting forth designs and then discarding them when they don’t work in the long run. It’s not a widely accepted model, but I think it holds water, because selection pressures could change as a species develops from one small population to a larger group of multiple populations.

Many more possible examples of Discontinued Products can be mentioned, like early Tetropods with multiple digits (like Ichthyostega and Ventastega), or even whole groups, like Placoderm fish. Once you recognize evolution taking place on higher levels than the gene, it is possible.

Knowledge feedback

With the Discontinued Products, I’ve come to the end of my definitions of evolutionary failures. As I pointed out, all failures except type II (the Monstrous Horde) are probably expected by evolution, and in all cases have I mentioned specific examples. What this means is that evolution gives us a reliable image of the evolution we know from biology, but fossils can also give biologists an idea about how evolution works. There is a feedback process from both fields contributing to the knowledge about the history of life.

Returning to Joe Bruno, I would ask him if this has given him the feeling that he has come to grips somewhat more with evolutionary theory in paleontology. Both the incredulity argument and the lack of knowledge should be removed. Unless he never wanted them removed in the first place, that is.