Extraordinary soft-bodied fossils highlight the Cambrian explosion

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  • เผยแพร่เมื่อ 26 ส.ค. 2020
  • The discovery of soft-bodied fossils at sites such as the Burgess Shale in Canada and Chengjiang in China have revealed that a remarkable diversity of animals evolved in the oceans more than 500 million years ago. This lecture will provide a personal perspective, considering why exceptionally preserved fossils are well represented in Cambrian compared to later Palaeozoic rocks and what they tell us about the evolution of marine life. New discoveries have shown that relatives of some unusual Cambrian animals, including the giant Anomalocaris, persisted beyond the Cambrian only to go extinct later in the Palaeozoic. At the same time the Cambrian explosion established the major animal groups that inhabit the oceans of today in more familiar form.
    ​​​​​​​
    Derek Briggs is G. Evelyn Hutchinson Professor of Earth and Planetary Sciences at Yale University. A graduate of Trinity College, Dublin and the University of Cambridge he moved to Yale in 2003 from the University of Bristol in the UK. He is a former Director of the Yale Peabody Museum of Natural History. His research explores the evolutionary significance of exceptionally preserved fossils including the Cambrian Burgess Shale and the Ordovician Fezouata formations of Morocco. He uses laboratory experiments, coupled with analyses of specimens, to determine how soft tissues are fossilized through replication by minerals and the diagenesis of organic cuticles. He has contributed to discoveries on fossil groups of various ages ranging from the vertebrate affinity of conodonts to the color of feathered dinosaurs.
    ​​​​​​​*Please note, this lecture may not be suitable for young children, but is suitable for adults and young people - beginners and experts welcome!
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ความคิดเห็น • 96

  • @charleslaine
    @charleslaine 2 ปีที่แล้ว +5

    I am always amazed when I see how remote and how high the Burgess Shale is. What a mind blowing discovery.

  • @LamgiMari
    @LamgiMari 3 ปีที่แล้ว +25

    Fantastic in-depth presentation! Shame that so few people are watching it. It deserves a lot more.

    • @Darisiabgal7573
      @Darisiabgal7573 3 ปีที่แล้ว +1

      I’m watching, that’s what matters😁

    • @Egma_1237
      @Egma_1237 2 ปีที่แล้ว +1

      They should do some Minecraft vids

    • @harryf1867
      @harryf1867 ปีที่แล้ว +1

      This lecture has legs: Watching for the first time 2 years later and at the moment it is up to 38k views. Utterly fascinating to see so much progress made since Stephen Jay Gould's book which I read ~30 years ago.

  • @judahwest1025
    @judahwest1025 3 ปีที่แล้ว +25

    This presentation is quite fun when you pretend the beginning is a seance summoning Derek.

    • @breimalislobodnoime
      @breimalislobodnoime 3 ปีที่แล้ว +5

      I read ur comment before I got to that part, so when it started I couldn't stop laughing

    • @simonmasters3295
      @simonmasters3295 3 ปีที่แล้ว +1

      I read it long after. When the talk became kinda so amazing I had to distract myself back into normal TH-cam viewing mode! Smiles

    • @williamchamberlain2263
      @williamchamberlain2263 ปีที่แล้ว

      Raising the spirits of researchers long passed to divulge the secrets of the netherworld.

  • @ZenFuKid
    @ZenFuKid 3 ปีที่แล้ว +8

    Fascinating, and so well presented. I'm happy to know this kind of progress is underway.

  • @scottzema3103
    @scottzema3103 3 ปีที่แล้ว +3

    Interesting how these strange animals are not so strange as was previously thought with respect to relation to known species.

  • @gerrardjones28
    @gerrardjones28 2 ปีที่แล้ว +2

    Very interesting, thank you!

  • @danieltokar1000
    @danieltokar1000 2 ปีที่แล้ว +3

    I think the 10 min. of preamble is what puts people off. All the important information about the speakers could go in the description , not the video.The content is wonderful.

    • @gandydancer9710
      @gandydancer9710 ปีที่แล้ว

      Not just in the preamble, the host is an oblivious twit. Insufferable.

    • @williamchamberlain2263
      @williamchamberlain2263 ปีที่แล้ว

      @@gandydancer9710 cry more

    • @williamchamberlain2263
      @williamchamberlain2263 ปีที่แล้ว +1

      Good point. It's normal to give the speakers' background and qualifications for lectures, but that's not the same as watching a TH-cam video

    • @gandydancer9710
      @gandydancer9710 ปีที่แล้ว

      @@williamchamberlain2263 ES&D, nitwit.

  • @billymania11
    @billymania11 2 ปีที่แล้ว

    This presentation was a cut above most others. Very well done and of course Mr. Briggs is brilliant as always.

  • @skronked
    @skronked 3 ปีที่แล้ว +8

    The Cambrian explosion RULES!!

  • @DAVIDPETERS12C
    @DAVIDPETERS12C 2 ปีที่แล้ว +1

    Key to understanding 'weird' fossils is to: 1) not forget that flatworms had/have circular ventral mouth parts and are basal to all bilaterals; 2) ribbon and round worms are basal to most (not all) taxa with a mouth on one end and an anus on the other, or slightly below a short extension that could be an adhesive production area or a mobile muscular tail originally used for burrowing and travel, as in basal chordates; 3) segmented taxa, like arthropods, are close to segmented worms like velvet worms and annelids; 4) unsegmented taxa, like echinoderms, molluscs and chordates are also close to one another. Hagfish, nautiloids and certain round worms share tentacles around a subterminal mouth with eversible mouth parts with teeth. Some flatworms and Tullimonstrum have a mouth-like extendable 'trunk' used to anchor it. Finally, flat, swimming semi-segmented to segmented taxa, like Anomalocaris and trilobites, can arise directly from semi-subdivided flatworms with twin antennae that convergently develop a separate terminal anus.

  • @crowesarethebest
    @crowesarethebest 3 ปีที่แล้ว +2

    Very informative. Thanks for posting

  • @woodsplitter3274
    @woodsplitter3274 3 ปีที่แล้ว +5

    Read "Wonderful Life" by Stephen Jay Gould. All about the Burgess Fossils. He wrote about Briggs very highly.

  • @Ometecuhtli
    @Ometecuhtli 3 ปีที่แล้ว +3

    Oops... indeed I just had breakfast. Interesting talk so far, love the diversity of photographs and illustrations and how they're used to home on the point you're making or subject at hand. Not a dull moment, I'm learning a lot :)

  • @marc-andrebrunet5386
    @marc-andrebrunet5386 3 ปีที่แล้ว +9

    🎯We got very beautiful cambrian fossils here in Montreal Canada... I found some very nice specimens on few church walls ..
    I do my best for identification but because I'm only amateur the job is very hard!
    Thanks for giving me a lot of information
    🥂 😷👍

    • @Brett733
      @Brett733 2 ปีที่แล้ว +3

      even for experts, identification is difficult. I am a geologist and we are more interested in the formations these fossils are found in and the conditions and mechanisms that led to there preservation. Even so, there are many scenarios where 10 different geologists will give you 10 different opinions on the origins or identification of a specimen which is why we resort to testing methods such as radiometric dating, mass spec, atomic absorption, stratigraphic dating, etc... I picked Geology because it didn't require any Biology prerequisites and at the time there were lots of jobs in mining/geology. Even so, there are times it is more art than science.

    • @gerrardjones28
      @gerrardjones28 2 ปีที่แล้ว

      Go to the burgess shale

  • @BiscuitBeetle
    @BiscuitBeetle 2 ปีที่แล้ว +2

    Amasing. I'de be interested in how furca is described as an arthropod? do you have more information as it looks to me like a cinadarian.

  • @VeronicaCawelti
    @VeronicaCawelti 3 ปีที่แล้ว +3

    Such an excellent lecture! This grasps my love of biology and history that have caused me to delve deeply in to many different disciplines with great joy. Another thing I am grateful for is politics don't yet effect this branch of science as it does paleoanthropology. An example being Cheddar Man. As if we "common" folk don't understand Cheddar Man likely had much more Neandertal DNA than we do today and was more "white" than we are. Shame on them for lying to mollify BLM. I pray that weakness doesn't spread to other disciplines.

  • @jongtes5570
    @jongtes5570 3 ปีที่แล้ว +2

    Love this. Calling from Beaumont Texas

  • @princewurst
    @princewurst 3 ปีที่แล้ว +3

    Thank you for making available such fascinating research insights to laymen like me!
    Regarding the map shown around 31:00, I wonder how the scientists (I'd guess geologists?) are able to reproduce how the Earth looked like 550 Mio years before?
    The biggest part of the landmass seemed to have been on the southern hemisphere then.
    How do we know this?
    And is there a certain uncertainty for these models?

  • @Dragrath1
    @Dragrath1 3 ปีที่แล้ว +3

    Oh cool he was one of the researchers to first identify the true nature of the first radiodont anomalocaris. Regarding radiodonts what blows my mind is how over my lifetime they went from obscure Cambrian dead end organisms to a much more diverse and lasting lineage with Ordovician suspension feeders and even late fossil specimens known from Lagerstatten as recently as the Devonian. It is a sad nature of the fossil record that we may never know how long any given evolutionary lineage really lasted or even a fraction of the full biodiversity of life on Earth. Regarding Lagerstatten isn't there also evidence to suggest anaerobic conditions played a role in many of their formations? I know the oxidation of the oceans has been quite variable over the Earths history really starting near the Great Oxidation Event then dropping off after the first snowball interval and only resurging in the Neoproterozoic there was an interesting paper in nature communications regarding the study of modern pelagic photoferrotrophs which provides an interesting case for the late oxygenation of the atmosphere being linked to photoferrothrophs being more evolutionarily fit at utilizing resources as anaerobic bacteriochlorophylls are able to efficiently photosynthesize in deeper waters meaning high nutrient flux diffusing from the seafloor. Its an interesting hypothesis that energetically makes sense as the stronger bond will take more energy to break meaning higher energy photons are needed. In that picture the oxygenation pulses required an excess of nutrients mainly phosphorus to photosynthesize. In such a model the evolutionary arms race between iron and or sulfur based respiring organisms and aerobic organisms might have gotten fairly tough with the equivalent of a metabolic arms race that continues to this day in remote environments.
    As for the interaction between trilobites and anomalocaris and other radiodonts I imagine the bite marks could in either case be explained during the molting phase where they like other arthropods would be vulnerable and in nature today predators and indeed even non predatory animals when provided the opportunity tend to be opportunists plus different radiodonts were probably specialized for different prey generally based off modern examples natural systems turn out more complicated than our models and hypothesis tend to suggest. Also a missed opportunity when talking about the lobopods to mention the third extant lineage the tardigrades.

  • @jazzsaz
    @jazzsaz ปีที่แล้ว

    Great work

  • @enterthecarp7085
    @enterthecarp7085 3 ปีที่แล้ว +2

    Good good info! Cheers!!

  • @modelleg
    @modelleg 2 ปีที่แล้ว

    Great stuff. Fascinating.

  • @scottzema3103
    @scottzema3103 3 ปีที่แล้ว +1

    I am reminded of stories where excavators often smell peculiar decay in relation to dinosaur fossil excavations. Why this doesn't suggest soft tissue survival in these animals is not clear.

  • @kevinbull9284
    @kevinbull9284 3 ปีที่แล้ว +4

    A fascinating presentation. Some interesting developments since Stephen Jay Gould first presented these amazing animals to the general public.

    • @TheShootist
      @TheShootist 2 ปีที่แล้ว

      yeah, he was wrong about so much.

    • @Raydensheraj
      @Raydensheraj 7 หลายเดือนก่อน

      Gould was NOT the "first one" to present these to the general public. He just wrote a book (with many falsified claims) that was quite successful...

    • @Raydensheraj
      @Raydensheraj 7 หลายเดือนก่อน

      Gould was NOT the "first one" to present these to the general public. He just wrote a book (with many falsified claims) that was quite successful...

  • @phantomofkrankor3665
    @phantomofkrankor3665 2 ปีที่แล้ว +1

    Seems like connectivity issue is the 21st century version of a failing slide projectors 😋

  • @NuisanceMan
    @NuisanceMan 3 ปีที่แล้ว

    When Simon Conway Morris saw Hallucigenia, he was like, "WHOAH, man, I'd better... come down."

  • @mobieus7
    @mobieus7 4 หลายเดือนก่อน

    Watched a few of these and there is a strong impression the intended audience is 8-12 years of age. Very puzzling.

  • @nyttag7830
    @nyttag7830 3 ปีที่แล้ว +3

    Once we were all sea cucumbers, not much has changed.

    • @maxsmith695
      @maxsmith695 3 ปีที่แล้ว

      My family were small sea crabs. Some decided to remain sea crabs for the past 10,000 years and other decided to become seals, then sharks, then monkeys, then humans. Evolution is easy to understand. t is so cool knowing my relatives are still sharks.

    • @williamchamberlain2263
      @williamchamberlain2263 ปีที่แล้ว

      Analogy between Sea Squirts and some professors: once they find an attachment point on rocks/get tenure they absorb their brains and settle down to passing material out of their butts.

  • @robbie_
    @robbie_ 3 ปีที่แล้ว +3

    I prefer my pineapple rings without jaws! Great talk, thanks for sharing.

    • @NuisanceMan
      @NuisanceMan 3 ปีที่แล้ว

      You prefer to eat them rather than being eaten by them? How odd.

  • @christophvonknobelsdorff1936
    @christophvonknobelsdorff1936 หลายเดือนก่อน

    film tear at the crucial point ? ...

  • @esoteric_Derek
    @esoteric_Derek ปีที่แล้ว

    OMG, thank you so much! You have solved 2 of the mystery fossils I have been trying to identify! Then there's one bigger mystery, tied to one of them that PLEASE CAN ANYONE HELP EXPLAIN?!! Please read the end of this comment and maybe someone can help me understand something odd about 1 of the fossils I have.
    But 1st, the trilobite @12:00 is identical to one I have in fragments, found in Kokomo, IN inside a hematite concretion when I broke it open! I have just started casting the pieces in epoxy resin.
    Now the 2nd fossil, that I now am seeing is some kind of bristleworm(s) that is encased in local Howard County, Indiana limestone that I have been soaking in HCl solution to release more of the fossil, something very odd(in my opinion) has been releasing from within the dissolving limestone that I can't make sense of.
    Can someone please watch the video I compiled of microscopic clips and some stills of this debris that I collected from the acid bath solution while checking the progress on the fossil, that you can see is clearly soft, fleshy tentacle-like tubes that look under the microscope like they could have been alive just yesterday!
    Please!! watch this video and tell me WTF is this stuff, and what creature it comes from??
    th-cam.com/video/7h3EeR31mZE/w-d-xo.html

  • @JorgeLopez.888.
    @JorgeLopez.888. 2 ปีที่แล้ว

    How long takes a soft bodied animal to turn in fossil?

  • @peterolbrisch1653
    @peterolbrisch1653 3 ปีที่แล้ว +3

    Who knew that the roots of the cannabis explosion went back that far?

    • @NuisanceMan
      @NuisanceMan 3 ปีที่แล้ว +5

      That reminds me of a T-shirt I used to see in high school: "I'm not as you think I stoned I am."

  • @jeshika22
    @jeshika22 ปีที่แล้ว

    I'm surprised that people don't point to the advent of predation as a very likely cause of the need for an explosion of species, in addition to the increase of temps and oxygen and opening up of new ecosystem niches as a result of all of the above. Predation would cause an arms race and the arms race in addition to the warming and oxygenation would both lead to the development of new ecological niches.

  • @guym-
    @guym- 3 ปีที่แล้ว

    There seems to be a problem between the talk and what appears on the screen. It is not possible to relate the spoken word to the pictures.

    • @morethanadodo
      @morethanadodo  3 ปีที่แล้ว +2

      Yes, apologies for this. We're looking into what's gone wrong now and will fix the video as soon as possible.

  • @juliehoffman6292
    @juliehoffman6292 3 ปีที่แล้ว +1

    Hello from Ohio,USA

    • @maxsmith695
      @maxsmith695 3 ปีที่แล้ว +1

      Friendliest state in USA.

    • @juliehoffman6292
      @juliehoffman6292 3 ปีที่แล้ว

      @@maxsmith695 thank you

    • @maxsmith695
      @maxsmith695 3 ปีที่แล้ว

      @@juliehoffman6292 - Not sure who does the polls, but I think it is real. Nicest people I have met, ( and funniest ) call Ohio home.

  • @DomingosCJM
    @DomingosCJM 3 ปีที่แล้ว +1

    What about high radiation preserving soft tissue?
    And if this high radiation happened once giving us the sensation of an "explosion" when it could be just a single event?
    How this soft tissue is preserved in nature, out of laboratory?

    • @williamchamberlain2263
      @williamchamberlain2263 ปีที่แล้ว

      You mean like a local high concentration of uranium ore or similar slowing down or preventing the decay process? That's an interesting question.

  • @dongentle6896
    @dongentle6896 2 ปีที่แล้ว

    Kudos, pronounced “Ediacaran” correctly.

  • @davidwilkie9551
    @davidwilkie9551 3 ปีที่แล้ว

    Excellent Review.
    Evolution/Conception in continuous temporal perspective of coherence-cohesion objectives, centred on Superspin/Singularity superposition spin-spiral, -> logarithmic condensation probabilities corresponding to a Math-Phys-Chem and Geometry wave-package here-now-forever.
    Which is WYSIWYG pulse-evolution projection-drawing holographic Singularity-point objective-imaging => vertices in vortices orthogonality perspectives, all operating on empirical shaping laws, all-ways in a unified/holistic vibrating Now.
    (Not just linear sequences of pages in the Celestial mapping system, that seems to be the default perception, although this is how we assemble visual images in Mind/Imagination)

    • @quantumcat7673
      @quantumcat7673 3 ปีที่แล้ว +2

      Lot's of baseless assumptions here to say the least.

    • @NuisanceMan
      @NuisanceMan 3 ปีที่แล้ว +1

      @@quantumcat7673 More like indecipherable statements.

  • @iangillham9647
    @iangillham9647 3 ปีที่แล้ว

    Why not edit out the gap? Very very lazy.

  • @GETMONEYJONES2304
    @GETMONEYJONES2304 11 หลายเดือนก่อน

    It is giant snails that are invading people's home right now along with locust We are in pestilence book revelation

  • @garygevisser1262
    @garygevisser1262 3 ปีที่แล้ว +3

    You talk too much

    • @NuisanceMan
      @NuisanceMan 3 ปีที่แล้ว +1

      You think too little.

    • @garygevisser1262
      @garygevisser1262 3 ปีที่แล้ว +1

      @@NuisanceMan my wife says "if you only knew." People with little intelligence have great difficulty feeling stupid! ~ MDG

    • @maxsmith695
      @maxsmith695 3 ปีที่แล้ว

      @@garygevisser1262 You have a point.

    • @garygevisser1262
      @garygevisser1262 3 ปีที่แล้ว

      @@maxsmith695 what is your profession?

    • @gerrardjones28
      @gerrardjones28 2 ปีที่แล้ว

      It's just the accent