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Examples of Living Fossils

Updated on August 12, 2012
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The Theory of Evolution predicts that living things will change over time, and the fossil record clearly shows that life on Earth has undergone a long history of gradual change. However, there have been some plants and animals that were so well-adapted to their environments that they have remained largely unchanged for many millions of years.

These species, which have survived mass extinctions, continental shifts, and changing climates over millions of years, are referred to as living fossils. In common usage, the term living fossil is used to describe any plant, animal, or microbe with a long evolutionary history, but scientists have a much more specific definition. To be a living fossil, a genus or species must have no other close living relatives. An organism that survived a mass extinction period but then radiated into multiple new orders would not be considered a living fossil. Birds, for this reason, are not considered living fossils even though their lineage dates back to the dinosaurs.

This article discusses the nautilus, the ginkgo plant, and the coelacanth - three excellent examples of living fossils still with us today.

Mineralized nautilus fossil at the American Museum of Natural History
Mineralized nautilus fossil at the American Museum of Natural History | Source

Living Fossil Example One: Nautilus

It should come as no surprise that a creature as prehistoric-looking as the modern nautilus is considered a living fossil. Their pinhole eyes, chambered shells, and soft bodies with as many as ninety tentacles certainly look like something that would be more at home in the Cambrian than the oceans of today.

The nautilus evolved during the late Cambrian period, around 500 million years ago, and reigned as the dominant sea predator for the next hundred million years or so. Even after bony fish and sharks came to dominate the world's oceans, the many species of nautilus and ammonites, their distant coiled-shell cousins in the cephalopod lineage, continued to occupy a niche as both scavenger and predator.

The Nautilidae family, which became the modern nautilus we know today, first emerged about 215 million years ago in the Late Triassic. According to the fossil record, the Nautilidae survived through the Jurassic and Cretaceous periods with only minor structural changes. They then began to diversify after the Cretaceous-Tertiary (K-T) mass extinction, an event that saw the extinction of the ammonites. The rapid diversification of nautilus species after the K-T extinction suggests that the nautilus began to thrive in the niches left behind when the ammonites went extinct.

Today, the nautilus may be poised for a new period of diversification and speciation. The existing nautilus populations living around islands of the West Pacific are disperse and isolated from each other - a textbook demonstration of the accepted mechanism for branching of new species.

60 million year old fossilized ginkgo leaf
60 million year old fossilized ginkgo leaf | Source

Living Fossil Example Two: Ginkgo

The ginkgo tree is a true survivor, in every sense of the word. These extremely resilient plants are resistant to pollution, insects, fungi, weather, and even atomic blasts. Some living ginkgo trees have been found to be more than 2,500 years old. The species itself has survived numerous mass extinctions and periods of climate change over its nearly 200 million year history, making it one of the best known examples of a living fossil.

Ginkgo is a rather odd tree specimen, with unusual leaf structure and reproductive strategy. Ginkgo plants are gendered, with male plants producing flagellated sperm and female plants producing dangling ovules. This dioecious type of reproductive system, as it is known in botany, is rare in modern plants but quite common in fossilized plants from the Jurassic period.

The first fossils considered part of the ginkgo genus date back to the Lower Jurassic, about 190 million years ago, fossils of ginkgo ancestors have been found in rocks from the late Permian, 270 million years old. During the middle Jurassic, the plant spread throughout Laurasia - the supercontinent that would eventually become North America, Europe, and Asia - and diversified into five or six ginkgo species.

During the Cretaceous, the fossil record shows a drop in ginkgo diversity and geographic reach as flowering plants began to dominate the plant kingdom. The species ginkgo adiantoides survived the Cretaceous-Tertiary mass extinction event and thrived for a while in the then-tropical climate of the northern hemisphere. As Earth's climate began to cool in the Oligocene and Pliocene, ginkgo slowly disappeared from the fossil record - first in North America, then Europe.

By the time humans evolved, ginkgo biloba was confined to a few mountainous regions of China. The species may have died out altogether had it not been cultivated by Buddhist monks who considered the plant sacred. These monks later brought the plant down from the mountains and helped it spread throughout East Asia. Contact with westerners then spread the plant to Europe and North America.

Coelacanth specimen at the Natural History Museum of Nantes
Coelacanth specimen at the Natural History Museum of Nantes | Source

Major Coelocanth Findings

show route and directions
A markerFirst Living Coelocanth Found -
East London, South Africa
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December 22, 1938

B markerSecond Living Coelocanth Found -
Nzwani, Comoros
get directions

December 20, 1952

Living Fossil Example Three: Coelacanth

The coelacanth is not only one of the most classic examples of a living fossil, but it was also one of the first fossils to be discovered during the modern era of paleontology. The first coelacanth fossils were discovered in the early 19th Century, well before the publication of Charles Darwin's On The Origin of Species. The name coelocanthus was coined by Swiss paleontologist Louis Agassiz in his 1836 book Poissons Fossiles, using the Greek terms koilos (hollow) and akantha (spine) to refer to the hollow bones of the fossil's tail fin.

Fossils of the coelacanth order first appear in the fossil record in the Early Devonian period, 407-409 million years ago. Coelacanth fossils can be found from the Triassic, Jurassic, and Cretaceous periods, but disappear abruptly from the fossil record at the K-T boundary 65 million years ago. For more than a century after the coelacanth's discovery, it was believed to have gone extinct during this mass extinction.

This belief was overturned on December 22, 1938, when a living coelacanth was caught by a fisherman off the coast of South Africa and found in his catch by a museum curator named Marjorie Courtenay-Latimer. At the time, Courtenay-Latimer had been encouraging local fishermen to donate unusual specimens to her museum's collection, and quickly realized the importance of this unusual find.

Since 1938, additional specimens have been found in the waters near East Africa and indonesia, and a sizable population has been found living near the Comoros archipelago between the east coast of Africa and Madagascar.

Although the coelacanth has survived numerous mass extinctions, it is threatened today by fishing activity off the coast of Africa. Coelacanth feed in the same waters and at the same time as oilfish, a lucrative catch for fishermen in the region, and are often caught in fishing nets and trawlers. As coelacanth meat is nearly inedible and unfit for human consumption, encouraging locals to preserve this fish is an uphill battle for conservationists looking to save this living fossil.

Poll Time!

Do you think living fossils disprove the Theory of Evolution?

See results

Don't Living Fossils Disprove Evolution?

The theory of evolution predicts quite accurately that living things change over time. It does not require that all living things undergo drastic change. When a species is well-adapted to its environment and resilient enough to survive changes to this environment, new traits occurring by random mutation are unlikely to take over a population.

The term living fossil does not mean that these species have undergone no change over millions of years - they have undergone some small changes along the way. Compared to the drastic diversification of other plant and animal species during the same time periods, however, the pace of evolution of these living fossils has been glacial.

Living fossils do not disprove or even cast doubt on the theory of evolution. They instead provide paleontologists and modern biologists a useful glimpse of the distant past.

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    • osaeoppongde profile image

      Deborah L. Osae-Oppong 4 years ago from Chicago, IL

      Thanks for sharing! Very interesting. I appreciate your conclusion!

    • DRG Da Real Grinc profile image

      Felix J Hernandez 5 years ago from All over the USA

      Awesome knowledge intake.

    • Jonathan Grimes profile image

      Jonathan Grimes 5 years ago from Devon

      Interesting hub on a great subject. I am sure there are many other living fossils out there. The Coelacanth finds are proof that we think we know every part of this planet and there are animals out there from long gone ages. We are just passing through.

    • nicomp profile image

      nicomp really 5 years ago from Ohio, USA

      "Yes, in the same way that a single letter is just slightly different from an entire novel."

      Good. We agree on something else.

    • scottcgruber profile image
      Author

      scottcgruber 5 years ago from USA

      "As you know, a bacteria mutating into a different bacteria is just *slightly* different than a light sensitive cell mutating into technicolor binocular vision. "

      Yes, in the same way that a single letter is just slightly different from an entire novel.

    • nicomp profile image

      nicomp really 5 years ago from Ohio, USA

      "You asserted that evolution doesn't happen. I proved you wrong with a single example."

      Certainly not, but it's your sandbox so you can make the rules. As you know, a bacteria mutating into a different bacteria is just *slightly* different than a light sensitive cell mutating into technicolor binocular vision. Feel free to define the terms any way you want, just remember this sage wisdom from Douglas Adams:

      "...Man then goes on to prove that black is white and gets himself killed at the next zebra crossing."

      Let me know when you get your eye hub written and I'll pick it apart for you. No worries.

    • scottcgruber profile image
      Author

      scottcgruber 5 years ago from USA

      "However, the only mutation you can point to is a bacteria mutating a resistance to a drug. "

      You asserted that evolution doesn't happen. I proved you wrong with a single example. I was not trying to correct all of your misconceptions by providing a comprehensive guide to every single feature evolution has produced over 3 billion years in one Hub comment.

      You have provided me with some good ideas for future articles, however. In the next few weeks I'll try to tackle the evolution of flight, how dinosaurs became birds, and how the eye evolved. Anything else?

    • nicomp profile image

      nicomp really 5 years ago from Ohio, USA

      At some point in time, according to your model, flight evolved through a series of minute mutations. According to your model, complex systems evolved in parallel through a series of minute mutations. According to your model, these systems evolved interfaces with each other.

      However, the only mutation you can point to is a bacteria mutating a resistance to a drug. You have a bacteria mutating into a different bacteria. You have no evidence to support your model.

    • davenmidtown profile image

      David Stillwell 5 years ago from Sacramento, California

      "well...ummm...because stromatolites couldn't fly."

      Flight does not equal evolution. Many species evolve but never develop flight. Flight may actually be an inhibitor to evolution. Since populations of organisms that can fly can fly off elsewhere to find new resources and develop new niche. It is when the resources become less over periods of time that we see evolution. Again, I point at Darwin's Finches. Despite the fact that they could fly, they could not escape their island habitat and as resources on an island are limited they evolved to fill the available niche. I think of Mendel and his peas and it seems so clear. Genetic representation of those organisms that acquire the most resources equates (mostly) to successful breeding and passing genes from one generation to the next. Those organisms that are not able to take advantage of the resources within the niche breed less or die off... It is not difficult to see this. It has nothing to do with God. The development of new species is a simple law of nature.

    • nicomp profile image

      nicomp really 5 years ago from Ohio, USA

      ""hmmmm.... why does evolution have to be complex or form a complex system?""

      Well... ummm... because stromatolites couldn't fly.

    • nicomp profile image

      nicomp really 5 years ago from Ohio, USA

      "It's such a simple concept. I don't understand why you science deniers can't grasp it."

      Translation: 'It's simple so it must be true. You're a moron if you don't get it. Close your eyes and imbibe the Kool-Aid.'

    • Insane Mundane profile image

      Insane Mundane 5 years ago from Earth

      I'm not a science denier, but I have never seen any real proof that separate species can morph into other, totally different species. Don't get me wrong, it would be so nice if we could simply explain one species from the next, but the theory of evolution creates more jokes than a solution, when attempting to tackle such queries. I'm absolutely unbiased, but yet, I find myself laughing at the current "scientific notions" of origin. Sorry... LOL! Please help me understand such things, as I will quickly grasp onto any non-divine idea that makes sense, just so your "scientific" hypothesis does...

      You must admit, nature does beckon for your imagination to factor in and Mother Nature never requires science class, so the day people quit pretending to know it all, may be the day we start learning after all... :D

    • scottcgruber profile image
      Author

      scottcgruber 5 years ago from USA

      "Evolution, when simply put, is just a mere acclimation and adaption of separate species"

      Correct. And when two populations within a species separate and acclimate and adapt to different environments, they eventually become new species. And as these all radiate and adapt over even more time, the new species become new genuses. And so on.

      It's such a simple concept. I don't understand why you science deniers can't grasp it.

    • Insane Mundane profile image

      Insane Mundane 5 years ago from Earth

      Evolution, when simply put, is just a mere acclimation and adaption of separate species, yet many evolutionists try to find all the answers through this baloney belief - even the spawning of life from a miraculous substrate - while ignoring the core substrate at hand. The silly "Theory of Evolution" doesn't even touch upon creation, as it becomes down-right asinine, when it tries.

      Oh, but the discord follows...

      By the way, the whole "living fossils" thingy, is just an excuse at prior debunking attempts from religionists, as I'm not fooled one bit.

      Better yet, please explain to me why you think the substrate of life isn't divine in its own right?

      What? Miracles happen?

      Imagination does have a reason for existing, so please feel free to use it, no? :/

    • davenmidtown profile image

      David Stillwell 5 years ago from Sacramento, California

      It seems kind of silly to me to argue over who owns a house that is on fire.

    • scottcgruber profile image
      Author

      scottcgruber 5 years ago from USA

      davenmidtown

      "hmmmm.... why does evolution have to be complex or form a complex system?"

      Because Creationists need to keep moving the goalposts, as the exchange above demonstrates. Once you've backed them into a corner and forced them to admit that evolution happens, they have to resort to claiming that macroevolution or speciation or "unique complex systems" cannot evolve through natural processes.

    • davenmidtown profile image

      David Stillwell 5 years ago from Sacramento, California

      hmmmm.... why does evolution have to be complex or form a complex system? When I think about Darwin's Finches it just seems so clear. Despite the genetic link to mainland Finch, those isolated communities evolved to meet the specific niche requirements of their environment....to the point that those physical traits became a constant through generation after generation...scientifically evolution is the genetic change within a family that results in a new species. It need not be complex or complicated.

    • scottcgruber profile image
      Author

      scottcgruber 5 years ago from USA

      "Agreed."

      So we are in agreement. Evolution happened.

      I accept your concession of defeat.

    • nicomp profile image

      nicomp really 5 years ago from Ohio, USA

      ""Now you're catching on. It's not a gain of information."

      And?"

      And the supposition that these mutations can accumulate into unique complex systems is impossible. Information is not added to the system.

    • nicomp profile image

      nicomp really 5 years ago from Ohio, USA

      "And I certainly don't see how this example cannot be considered evolution. Mutations to the genome caused a change in RNA that improved the survival odds of a strain of bacteria. That is a documented instance of evolution."

      Agreed. But your greater point, the issue that you're dancing around, it that your camp wants us to believe that these mutations can 'build up' into new systems. A mutated bacterium is still a bacterium. It's like a breeding a faster racehorse. You still have a horse.

    • scottcgruber profile image
      Author

      scottcgruber 5 years ago from USA

      "Now you're catching on. It's not a gain of information."

      And?

    • nicomp profile image

      nicomp really 5 years ago from Ohio, USA

      "So how is it either a loss or gain of information?"

      Now you're catching on. It's not a gain of information.

    • scottcgruber profile image
      Author

      scottcgruber 5 years ago from USA

      "You need to grasp the difference between a loss of information and an increase in information."

      Alright. Let's talk specifics. Resistance to the drug Rifampin in Mycobacterium tuberculosis. Rifampin works by binding to M. tuberculosis RNA and preventing it from transcribing properly, thus killing the bacterium.

      Sequencing of M. tuberculosis DNA from resistant and non-resistant strains has found that in 79% of the cases, the resistance was produced by point mutations (substitution of one base pair for another) in one of two codons on the gene rpoB. These point mutations caused the gene to substitute one amino acid for another, a change that prevented the Rifampin from binding to the RNA produced.

      Source: http://www.ncbi.nlm.nih.gov/pubmed/10645439

      Again, these are point mutations - changing an A to a G or a G to a C or a C to at T or any other permutation you like. The number of base pairs does not increase or decrease. The number of codons does not increase or decrease. So how is it either a loss or gain of information?

      Now I will qualify - in some other cases there were insertions and deletions, so I can see an argument being made in these cases that information was either gained or lost. But even then, I don't quite see the relevance.

      And I certainly don't see how this example cannot be considered evolution. Mutations to the genome caused a change in RNA that improved the survival odds of a strain of bacteria. That is a documented instance of evolution.

    • nicomp profile image

      nicomp really 5 years ago from Ohio, USA

      "Then you agree that evolution happened. Excellent. Glad to see you're finally making some progress."

      You're making the classic illogical assumption exemplified by all evolutionists. It's OK. I'll set you straight. You need to grasp the difference between a loss of information and an increase in information. You'll catch on.

    • scottcgruber profile image
      Author

      scottcgruber 5 years ago from USA

      "No."

      Then you agree that evolution happened. Excellent. Glad to see you're finally making some progress.

    • nicomp profile image

      nicomp really 5 years ago from Ohio, USA

      "Do you deny that multidrug-resistant pathogens exist?"

      No. Do you understand what that implies?

    • scottcgruber profile image
      Author

      scottcgruber 5 years ago from USA

      "Not very sciency of you."

      Do you deny that multidrug-resistant pathogens exist?

    • nicomp profile image

      nicomp really 5 years ago from Ohio, USA

      "Gotcha. So when an evolutionist refuses to participate in your Gish Gallop, you declare victory?"

      Over your arguments, yes. When the name-calling starts, I win.

      "Fair enough. Congrats on "winning" yet another game of pigeon chess."

      chirp chirp.

      "Not that it matters, of course. Evolution happened whether you believe in it or not."

      Not very sciency of you.

    • scottcgruber profile image
      Author

      scottcgruber 5 years ago from USA

      Gotcha. So when an evolutionist refuses to participate in your Gish Gallop, you declare victory?

      Fair enough. Congrats on "winning" yet another game of pigeon chess.

      Not that it matters, of course. Evolution happened whether you believe in it or not.

    • nicomp profile image

      nicomp really 5 years ago from Ohio, USA

      I know I'm on the right track when evolutionists respond this way.

    • scottcgruber profile image
      Author

      scottcgruber 5 years ago from USA

      Before you continue making a fool of yourself with ignorant comments on evolution hubs, you might want to learn a bit about it. Maybe then you'll at least come up with more original Creationist talking points.

    • nicomp profile image

      nicomp really 5 years ago from Ohio, USA

      "Birds, for this reason, are not considered living fossils even though their lineage dates back to the dinosaurs."

      No, they don't date back to flightless lizards. Flight from non-flight could not evolve from a series of tiny random mutations. The flightless lizards would be dragging around wings for millions of years waiting for their bones to hollow out and their neuro-muscular systems to randomly mutate control algorithms for take-offs, flapping, judging distances, flying, evading, perching, balancing, and landing. And it would be kind-of counter-productive for a pre-bird to jump out of a tree, hoping that everything had evolved just right on the first try. Unless evolution got everything perfect on the first mutation, the pre-birdy would be an ex-pre-birdy with a broken neck which makes additional random mutations problematic.

    • scottcgruber profile image
      Author

      scottcgruber 5 years ago from USA

      Great question, nicomp!

      The modern fish we call "coelacanth" is actually a multiple species of fish under the genus latimeria. DNA testing has shown the Comorian population and the Indonesian population to have some genetic differences. They also have different coloration - Comorian coelacanths are bluish and Indonesian coelacanths are brownish. That's one small change just in the last 30-40 million years.

      As for the dating of the old fossils, this was accomplished not by dating the fossils themselves, but by dating the rocks they were found in. For example, the oldest coelacanth specimen found to date, Eoactinistia foreyi, was found in the Fairy Formation in Victoria, Australia. This is a strip of fossil-laden sedimentary rock sandwiched between two volcanic flows. Dating of the lava flows on top of and below the Fairy Formation puts the dates of fossils found within that formation within the Devonian period. You can read more at the "Oldest coelacanth" article in the links capsule above.

    • Insane Mundane profile image

      Insane Mundane 5 years ago from Earth

      Yeah, the coelacanth didn't believe in the theory of evolution, either. The whole "theory of evolution" crap needs to be removed from the science genre and let real biologists get on with their work without this nonsense... Oh yeah, and a terradactyl turned into a duck and a "Raptor" turned into a turkey... LOL!

    • nicomp profile image

      nicomp really 5 years ago from Ohio, USA

      "The term living fossil does not mean that these species have undergone no change over millions of years - they have undergone some small changes along the way."

      And you know this ... how?

      What small changes has the coelacanth undergone over the last 300MY? By the way, how were the coelacanth fossils dated? It's interesting because since they were sea creatures, radiometric dating is pretty much out.

    • nicomp profile image

      nicomp really 5 years ago from Ohio, USA

      "The nautilus evolved during the late Cambrian period, around 500 million years ago, and reigned as the dominant sea predator for the next hundred million years or so."

      What did it evolve from?

    • K9keystrokes profile image

      India Arnold 5 years ago from Northern, California

      Outstanding read!

    • JKenny profile image

      James Kenny 5 years ago from Birmingham, England

      Great hub, anyone that doubts the fact of evolution need only take a look at this hub. It seems strange that many dispute evolution when it's as watertight as gravity. Great stuff. Voted up.

    • Christopher Dapo profile image

      Christopher Dapo and S. 5 years ago from Havelock, NC

      Wonderful and very informative article. Loved hearing about the Ginkgo, a remarkable tree!

      - Chris and S.

    • Electro-Denizen profile image

      Charles 5 years ago from Wales, UK

      very interesting to read

    • deenahere profile image

      Deena 5 years ago from India

      Informative and interesting hub.Thanks for sharing

    • Jenna Pope profile image

      Jenna Pope 5 years ago from Southern California

      Excellent hub. So interesting!

    • DzyMsLizzy profile image

      Liz Elias 5 years ago from Oakley, CA

      I am so tired of hearing, still in this day and age, about the "theory" of evolution! It has by now been well-proven as fact--and out of the realm of mere theory.

      I don't mean to imply that all life began as, for example, some kind of fish, and "evolved" into people, horses, or whatever.

      It is simply a matter of each life form evolves on its own timetable, as needed for survival. Horses, for example have always looked like horses, but the fossil record shows they were far smaller--about the size of rabbits; they still looked like horses, even so.

      For anyone who does not care to believe this gradual process, they only need look as far as species with far shorter lifespans--we have seen the process unfold before our eyes--DDT-resistant flies are just one example.

      That said, yes, there are many species that have not changed much, as you point out...alligators, sturgeon, sharks, snails, etc.

    • TrahnTheMan profile image

      TrahnTheMan 5 years ago from Asia, Oceania & between

      Great article! This is an example of a genuinely informative, accessible and interesting hub- what we should all aspire to! Thanks Scott- voted up!

    • davenmidtown profile image

      David Stillwell 5 years ago from Sacramento, California

      You are welcome.... Write more... I read a lot!!!

    • scottcgruber profile image
      Author

      scottcgruber 5 years ago from USA

      Wow! That's very kind of you - thank you very much for reading!

    • davenmidtown profile image

      David Stillwell 5 years ago from Sacramento, California

      I always love your work Scot! You inspire me in many ways.