Fossil Doesn’t Equal Failure

Hi all, Thanks again for tuning in. I recently had the opportunity to speak at the first annual national biomimicry forum and education summit. The following is a transcript of the talk I gave including some of the associated imagery. Hope you all enjoy Fossil Doesn’t Equal Failure:

We’ve all heard things that sounds true, and everyone treats as fact, but have proven to be false. The internet is littered with listicles about misconceptions that riddle our popular culture. See which of these statements about animals you can identify as misconceptions.

  • Goldfish have three second memories

  • Chameleons change color to blend in with their background

  • Most Birds cannot swallow

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As it turns out the only true statement of the above is for the birds. Goldfish have functional memories of up to 3 months. chameleons’ colors change according to their mood or body temperature but not their backgrounds. Most birds do not have the esophageal muscles required to swallow food and water so instead they must use gravity to assist moving food into the stomach.

These examples may seem silly, but they illustrate how misconceptions can easily get entrenched in popular thought, so much so they become hard to dislodge. The reason these and other misconceptions are so persistent in culture is due to a psychological phenomenon called cognitive ease, wherein we are more likely to think of something as true if what is being said is easy to process or seemingly more familiar. Consider now, this quote from Janine Benyus in a reader’s digest interview

“Ninety-nine percent of all species that existed on earth are extinct. The 1 percent here are the ones that work best. Think of our planet as a research-and-development lab in which the best ideas have moved forward, and the ones that used too much energy, or materials, or were toxic, were dropped. What you wind up with are organisms that are efficient.”

Or another quote from a blog post by Fran Sorin

“After 3.8 billion years of research and development, failures are fossils, and what surrounds us is the secret to survival.”

Notice how simply the essence of biomimicry is distilled into a sentence or two. The idea “fossil equals failure” seems on the surface to be true, and its presentation makes it neat and easy to digest. It’s no wonder then that these types of statements crop up all over across the biomimicry community. You might accuse me of being a nitpicking biologist getting his feathers ruffled over jargon and nuance. But these types of statements misrepresent the way evolution and extinction work. And this misrepresentation restricts those of us studying biomimicry to a tenth of a percent of all the organisms that have ever lived. By doing some quick math, we find that in focusing only on the 8 million species alive today we are missing out on 72 million extinct models to mimic. Is there any good reason why we reject the bulk of life’s history in favor of what is alive today? I would argue no.

These quotes and others like them are intended to illustrate the way natural selection shapes species to be optimally suited to their environments. Humans are storytellers. We have been for ages; and narratives are essential tools for understanding the world around us. But we have to be wary of improper narrative frameworks that lead to incorrect interpretations. The fossil equals failure paradigm sets up a narrative to help appreciate what we stand to gain from the natural world through biomimicry. By making a connection between the way nature solves problems and an R&D lab solves problems, biomimicry no longer seems foreign and alien.

According to this story the fossil record holds the crumpled sketches by the waste basket and the clunky prototypes gathering dust in the corner. But when we look at some of today’s organisms and peer just a little deeper into the fossil record and, we find that life has followed a very different narrative over the course of earth’s history.

Look back at Janine’s quote.

“Ninety-nine percent of all species that existed on earth are extinct. The 1 percent here are the ones that work best. Think of our planet as a research-and-development lab in which the best ideas have moved forward, and the ones that used too much energy, or materials, or were toxic, were dropped. What you wind up with are organisms that are efficient.”

I want to point out the efficiency clause. Certainly I cannot dispute that organisms in general are incredibly efficient machines. But we put the cart before the horse in saying that life evolved primarily to be efficient. In actuality we have many examples of perceived inefficiencies in organisms alive today. Birds are an obvious culprit, whose extravagant plumage and mating displays have confused evolutionary biologists as to their adaptive value. Sexual selection theory dictates that extravagant males indicate to females their fitness by their ability to maintain their ornaments despite the energy and safety costs they incur. And in watching either this peacock or this widowbird fly it becomes apparent that efficiency is not driving their evolution.

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We also have examples of organisms that are not as efficient as they ought to be. Pandas, for example, are not well suited to digest the bamboo of which the eat exclusively. Their gut flora still resembles that of more carnivorous organisms than obligate herbivores.

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Sea Horses have poorly developed stomachs meaning they cannot store food for later digestion and must eat almost constantly to survive.

What these types of organisms’ show is that selection is not always so exacting, nor can you point to a single over-arching factor that drives selection. Additionally, if efficiency is not the primary driving force in evolution then inefficiency is not necessarily the reason extinct species died off.

Returning again to Janine’s quote we find, “the best ideas have moved forward, and the ones that used too much energy, or materials, or were toxic, were dropped.” Here the imposition of higher value on species alive today creates an issue. In reality no species is safe from extinction. A poignant reminder of this is the passenger pigeon, once numbered in the billions now only exists in museum collections.

Extinction happens all the time, we call this the background extinction rate. When boiled down, extinction is the result of a population becoming too small to recover from depletion. The reasons a population reach that critical size reduction are many, and often have nothing to do with how well the species is are adapted to its environment.

 

We first have to consider chance. Stochastic effects like a random drop in fertility, deadly natural disaster, or uncharacteristic food shortage can set the ball rolling towards a population’s extinction. It seems illogical to expect dinosaurs to be able to cope with something as rapid and catastrophic as a meteor impact, especially if we then brand them as failures because they succumbed.

Some populations are more susceptible to extinction than others, especially those slow to react to environmental disturbance due to low fecundity or long generation times. Species with long generation times take longer to try new genetic combinations, meaning they are much slower in reacting to change. Populations with low fecundity do not bounce back from depletion as readily as others. In the time it takes to rebuild a population, genetic bottlenecking and inbreeding will have taken its toll on the populations genetic diversity. This blue whale is an example of a species with low fecundity and a long generation time.

Anim1754_-_Flickr_-_NOAA_Photo_Library

By NOAA Photo Library – anim1754, Public Domain, https://commons.wikimedia.org/w/index.php?curid=17942391

In biomimicry we praise certain organisms for their uniquely specialized adaptations. But in becoming specialized, a species increases the risk of going extinct. Selection by definition reduces genetic diversity. The traits under heavy selective pressure become fixed as the species becomes optimized for its environment. But in becoming so fine tuned to the current environment these species increase the likelihood of extinction when faced with environmental disturbance. Even small deviations from the norm can send a specialist spiraling toward extinction. The crossbill on the left has evolved a bizarre beak structure designed to pry open the scales of pine cones. The American goldfinch on the other hand has a more generalized beak that can make use of many different food sources. The crossbills success is directly tied to the well being of the conifers that support it while the goldfinch has more options when looking for food.

Extinction it seems is an occupational hazard of living on this planet. Selection shapes organisms to the environments in which they live. But the planet we live on is dynamic, and what worked yesterday may not work tomorrow.

 

So it seems life has not been pushing forward through history towards a greater ideal rather it has experienced episodes of, origination, diversification, and devastation. Allow me to illustrate by tracking the major themes of vertebrate evolution. After tetrapods colonize land in the late Devonian, a small lizard looking synapsid diversifies and soon synapsids dominate the ecosystems of the Permian,

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extinction strikes at the end of the Permian taking most of the synapsids with it, allowing an unlikely group of archosaurs diversify in their wake.

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They diversify into what we know as dinosaurs, who themselves are devastated at the end of the cretaceous allowing an unlikely group of mammals to diversify, accounting for the variety of mammalian forms we see today.

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Along the way we see repeating archetypes, for example: The large bodied herbivore, the apex predator, the herding grazer, etc.

These similarities are more than superficial, as often we see convergent evolution producing similar if not identical solutions to the same problem. A study by O’Brien et al. shows strikingly similar nasal domes in both lambeosaurs and a wildebeest relative from the Pleistocene called Rusingoryx. The authors of the study believe that both organisms used these structures to produce vocalizations that would have facilitated communication between members of their herds.

Rusingoryxhadrosaurclipping

O’Brien, Haley D., et al. “Unexpected Convergent Evolution of Nasal Domes between Pleistocene Bovids and Cretaceous Hadrosaur Dinosaurs.” Current Biology 26.4 (2016): 503-508.

If we held to a progressive view of evolution, we might wonder why a successful strategy would need to evolve twice. But if we see evolution as a series of cycles it makes sense that similar environmental problems would result in similar solutions.

 

We live in a snapshot of evolutionary history, and the organisms we find around us may best fit the evolutionary contexts in which they find themselves. But if we were to rewind to any point in history we would find that the organisms living then were no less suited to their respective environments than the organisms living now. You cannot directly compare fitness between species separated by time. It is foolish then to assume that extinct species are any less fit than species alive today. Scott Sampson has a great quote to this end,

“Dinosaurs were the dominant large bodied life forms on land for over 150 million years. Primates have been around for less than half that duration, hominids have been walking upright less than 8 million years, and humans have been present for less than a half million years. So it takes a lot of gall (or at least a severe case of temporal myopia) to claim some sort of victory over dinosaurs. You may as well snub your nose at your dead relatives because, after all, you’re alive and they’re not.”

So what are we missing when we exclude species that are not alive today? Aside from the 72 million potential natural models, we miss the context surrounding the organisms we want to mimic today. Think of the most quintessential desert mammal. Odds are you would have said the camel. The camel’s combination of water saving and thermoregulatory adaptations suit it perfectly for the hot dry deserts of north Africa and the middle east. But what if I told you that the camel’s lineage originated in the high arctic boreal forests of north America during the Pliocene?

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Natalia Rybczynski and her colleagues trace the incredible history of the camel lineage in a 2013 paper published in Nature communications. Understanding the camel’s evolutionary history changes the way we interpret its adaptations. We now have to consider how traits we associate with desert survival would have originated in colder climates. In doing so we open up opportunities to inspire innovation in ways we would not have considered without knowing more about the history of the lineage.

Evolutionary lineages vary in the amount of diversity they have over time. The assemblage of species we have today are often remnants of their once diverse clades. Consider elephants. Today both extant elephant species are endangered or vulnerable, but the fossil record shows that proboscideans were once a rich, diverse clade that came in a wide variety of shapes and sizes, living in all types of climates all across the globe. Elephants today have been the subject of many important and successful bio-inspired inventions, but how much more could we learn if we considered the rest of the lineage when we did biomimicry?

 

The biosphere today contains many organisms that exhibit feats of size and strength that blow our minds. But when looking for the biggest tallest and strongest, more often than not those titles go to extinct animals. Mammals today pale in comparison to some of their ancestors. Mammals during the Oligocene, from all clades experienced levels of gigantism not seen since the Mesozoic. The largest of these, paraceratherium, was a rhinoceros relative that lived during the Oligocene. It stood 20 feet at the shoulder and weighed upwards of 11 tons. Here paraceratherium stands in reference to a komatsu rock truck used in mines, and the largest land mammal today, an elephant.paraceratherium dump truck and elephant2

 

Many herbivorous mammals have teeth comprised of four different tissues that wear at different rates to maintain an effective cutting surface. Hadrosaurs of the late cretaceous had six, allowing them to better utilize the diverse flora during the cretaceous. Not only is this another example of convergence across time, it shows that today’s models do not necessarily represent the maximum possibility for a trait.

Hadrosaurdentitionclipping

The largest flying animal ever would have been roughly the size of a Cessna airplane. Quetzalcoatlus was a pterosaur with a wingspan of 35 feet. When grounded this animal still would have stood 17 feet tall, equal to that of giraffes. If we roll back even further in time to the Devonian, the age of fishes, we find the organism with one of the strongest bite-forces ever measured.

quetzalcoatlus vs cessna

Matt Martyniuk (Dinoguy2), Mark Witton and Darren Naish- Own work, CC by 3.0 https://commons.wikimedia.org/w/index?curid=4129661 (with modifications)

 

 

 

Dunkleosteus, a placoderm first discovered in the rocky river reservation, was estimated to have a bite-force of 80,000 pounds per square inch. This tremendous bite force allowed Dunkleosteus to prey on heavily armored arthropods, mollusks and other placoderms, with which it shared the Devonian seas.

Obviously being bigger, faster, or stronger doesn’t necessarily make you better. These extinct organisms and others like them were adapted to fit their own evolutionary contexts. In our built world we have created problem spaces that aren’t filled by today’s natural models, but we need to consider the possibility that nature in eons past may have solved problems we have today, that aren’t solved by our contemporary natural models.

Atlas V Rocket Launches with Juno Spacecraft

An Atlas V rocket launches with the Juno spacecraft payload from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida on Friday, August 5, 2011. The Juno spacecraft will make a five-year, 400-million-mile voyage to Jupiter, orbit the planet, investigate its origin and evolution with eight instruments to probe its internal structure and gravity field, measure water and ammonia in its atmosphere, map its powerful magnetic field and observe its intense auroras. Photo Credit: (NASA/Bill Ingalls)

The question now, is why don’t we see more paleontological natural models? Extinct organisms offer a veritable mine of untapped knowledge to the discerning biomimetic researcher, but in order to unearth the secrets of life’s history we must be prepared to sift through a number of challenges distinct to paleontology.

To start, Paleontologists are already working with an incomplete history of life. The natural world is incredibly efficient in recycling raw materials, therefore fossilization is a rare and difficult process. The rarity of fossilization means that the fossil record is only estimated to be 31% percent complete across all taxa. Some fossils are only known by a tooth or bone fragment. This diagram shows what we have found of pakicetus, a whale ancestor, and is still largely incomplete.

This makes building the tree of life difficult to say the least. For someone interested in biomimicry this creates problems when trying to trace the evolutionary history of the trait you are interested in mimicking. However, despite the holes in our knowledge we have managed to piece together the major themes and movements in the history of life. There is hope for filling some of those holes as we are currently living in a paleontological renaissance where new fossils are being discovered daily that only add to our understanding of life’s history on earth.

Another limitation we face stems from the types of fossils typically found. Soft tissues rarely fossilize in good condition, if at all. The majority of fossils we find are of bone and shell and exoskeleton. From these we can only infer so much about the organism, mainly about the organism’s body plan and biomechanics. With a little ingenuity and advancing technologies, todays paleontologists are applying new techniques to their study in order to discover new information about the life histories of extinct organisms. As computing power advances techniques like finite element analysis are becoming more and more important. FEA offers boundless insight into how these extinct organisms would have lived. A study by E.J. Rayfield that modeled the force distribution in various theropods skulls, showing how the T. rex skull was modified to withstand and deliver bone crushing bites. theropodjawclipping.gifThis figure from Arbor and Snively used finite element analysis to ask whether the ankylosaurus tail club could withstand the impact sustained while engaging in tail clubbing behavior.

anklosuarclipping

The Anatomical Record: Advances in Integrative Anatomy and Evolutionary BiologyVolume 292, Issue 9, pages 1412-1426, 26 AUG 2009 DOI: 10.1002/ar.20987http://onlinelibrary.wiley.com/doi/10.1002/ar.20987/full#fig7

Studying the cellular anatomy of extinct organisms’ sheds light on how they grew and developed, helps distinguish similar species, and even gives us clues as to the coloration of some dinosaurs. A figure from Rogers et al. shows cross sections of juvenile titanosaur femurs. By analyzing the bone histology, they were able to determine that young sauropods were independent at birth and that they grew rapidly and isometrically into their adult forms. titanosaurclipping.jpgDinosaur color has been the subject of much speculation and open to artist interpretation. Take for example this artist rendition of the famous bird transition fossil archaeopteryx.

The next figure shows evidence of melanosomes in an archaeopteryx feather. In a study to come out of the University of Akron Carney et. Al. decided, based on phylogenies, and melanosome morphology, that archaeopteryx feathers would have been black.

ncomms1642-f3

Carney et. al. 2012

 

Perhaps the paleontologists greatest, and oldest, tool is comparative anatomy. George Cuvier the father of comparative anatomy has a famous quote

 

Baron Georges Cuvier (1769-1832)

“At the sight of a single bone, of a single piece of bone, I recognize and reconstruct the portion of the whole from which it would have been taken. The whole being to which this fragment belonged appears in my mind’s eye.” Baron Georges Cuvier (1769-1832)

Bony processes and foramina tell us how muscles, blood vessels, and nerves interacted with the skeletal system. And by comparing these types of structures between extinct and extant relatives we can make educated guesses about the physiology of extinct organisms. This figure from Keegan et. Al. shows evidence of openings in the vertebrae of barosaurus which are similar to those found in modern birds, indicating that sauropods may have had an avian lung arrangement. Based on our understanding of how the avian lung works we can project what capabilities the lungs of dinosaurs would have had to have in order to support animals of their size. barosaurusclipping

Despite the difficulties associated with finding and understanding fossils creative and innovative minds have made tools like finite element analysis, histology, comparative anatomy, and many others available to open up the world of paleontology to the world of biomimicry. The more paleontology is allowed to mingle with other fields and acquire new techniques the more we can discover about the prehistoric world.

As pioneers in field of biomimicry, it is our job to push the limits of the field to discover what exactly it can do, and more so challenge what others think it cannot. We have to be willing to identify misconceptions and take them to task, or risk missing fertile fields of information ripe for research. The most important thing to remember, is that the natural world defies simplicity. And as messy and convoluted natural systems may be; there are certainly gems to be found that makes this process worthwhile. Beyond paleontology, I would implore you all to consider how embracing nuance and challenging misconceptions within your own fields can open previously closed doors in biomimicry and beyond.

Citations:

  • Erickson, Gregory M., et al. “Complex dental structure and wear biomechanics in hadrosaurid dinosaurs.” Science 338.6103 (2012): 98-101.
  • Melstrom, Keegan M., et al. “A juvenile sauropod dinosaur from the Late Jurassic of Utah, USA, presents further evidence of an avian style air-sac system.” Journal of Vertebrate Paleontology (2016): e1111898.
  • Rayfield, E. J. “Aspects of comparative cranial mechanics in the theropod dinosaurs Coelophysis, Allosaurus and Tyrannosaurus.” Zoological Journal of the Linnean Society 144.3 (2005): 309-316.
  • Arbour, Victoria M., and Eric Snively. “Finite element analyses of ankylosaurid dinosaur tail club impacts.” The Anatomical Record 292.9 (2009): 1412-1426.
  • Rybczynski, Natalia, et al. “Mid-Pliocene warm-period deposits in the High Arctic yield insight into camel evolution.” Nature communications 4 (2013): 1550.
  • Rogers, Kristina Curry, et al. “Precocity in a tiny titanosaur from the Cretaceous of Madagascar.” Science 352.6284 (2016): 450-453.
  • Carney, Ryan M., et al. “New evidence on the colour and nature of the isolated Archaeopteryx feather.” Nature Communications 3 (2012): 637.
  • O’Brien, Haley D., et al. “Unexpected Convergent Evolution of Nasal Domes between Pleistocene Bovids and Cretaceous Hadrosaur Dinosaurs.” Current Biology 26.4 (2016): 503-508.
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