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From some of the underwhelmed comments here, perhaps the significance of the Burgess Shale is not widely understood. This book is an amazing read and will expl

From some of the underwhelmed comments here, perhaps the significance of the Burgess Shale is not widely understood. This book is an amazing read and will explain it, if you're interested: https://www.bookdepository.com/Wonderful-Life-Stephen-Jay-Gould/9780393307009 https://www.bookdepository.com/Wonderful-Life-Stephen-Jay-Go... The Burgess Shale contains fossils from some of the earliest complex multi cellular life. Prior to this, for billions of years life was single cell or collections of single cell organisms. This is the time when complex life first appeared on earth, and the animals that evolved then were startlingly weird. And yes, most of them were very small. What seems to have happened, is that "one day" (in geological terms) there was nothing but single cell organisms, and essentially "next day" (again, in geological time frames) there was an absolute explosion of complex life/animals. Most interesting about life at this time is not just the diversity of life, but the diversity of fundamental types of animals. For some reason at this time evolution was free to come up with entirely new types of "animal designs", not just modifications of previously existing body types. Today, all animals on earth are classified into a very small number of basic types of animal - (perhaps only 5?). but many of the fossils found in the Burgess Shale are so strange that it's not clear that they belong to any known family of animals. This implies that back then there might have been many, many fundamental types of animal, today we are left with only a handful of basics types. There's even the suggestion that there are creatures that can't really be classified into plant or animal - it's not clear what they are at all. Forgive me if I get the above wrong - I'm no expert, just an enthusiast. Maybe others can provide more information about the basic types of animal and how this relates to the Burgess Shale. The Burgess Shale is a window into the absolutely most interesting time of earths history. An animal the size of a dog might have been the largest animal on earth.

ComputerGuru 5y ago
Just to add: if anyone is interested in learning more about the sudden appearance of extremely varied life, this event is called the “Cambrian explosion” and makes for some very interesting reading.
- thangalin 5y ago
  Cambrian Explosion is a bit of a misnomer because it leads people to think it was unique with respect to evolutionary processes. There is a push to call it the Cambrian Radiation [0]. Throughout complex life's time on Earth there have been multiple periods of rapid evolutionary development similar to the Cambrian. A blurb about the Cambrian Radiation appears in my coffee table picture book [1]. [0]: https://impacts.to/bibliography.pdf#page=41 https://impacts.to/bibliography.pdf#page=41 [1]: https://impacts.to/downloads/lowres/impacts.pdf#page=15 https://impacts.to/downloads/lowres/impacts.pdf#page=15
  - mkl 5y ago
    "Radiation" sounds more unique than "explosion" to me (not an evolutionary biologist). It sounds like it means there was some unusual atomic radiation causing mutations at that time, so I think it will lead to more misunderstanding by laypeople rather than less. Why did they decide not to have multiple "explosions"? Your book looks really interesting!
    - adrian_b 5y ago
      "Radiation" is meant to suggest that the evolution advanced in many very different directions, like the rays that diverge from a point. Such "radiations" have happened every time when there was little competition either because a new place or environment was invaded or because a catastrophe had eliminated the former incumbents. The result of evolution "radiations" was that some group of animals that previously had been more or less uniform because they were adapted to a certain niche, after the "radiation" event became diversified in a large number of groups adapted to very different conditions of life and having much less resemblance between themselves than before.
      - mkl 5y ago
        Yes I understand what it means, but the word "radiation" has other much more well-known meanings, one of which directly connects to having more mutations than usual, so it's bound to be misunderstood.
holler 5y ago
> There's even the suggestion that there are creatures that can't really be classified into plant or animal - it's not clear what they are at all. Could you expand on that at all? It sounds really fascinating.
- andrewstuart 5y ago
  All life of course at this time is in the ocean. There's things that look like ferns, and are attached to the sea floor. But they lived at such a depth that the sunlight would not have been able to reach them so they could not have been plants. https://en.wikipedia.org/wiki/Charnia https://en.wikipedia.org/wiki/Charnia "The living organism grew on the sea floor and is believed to have fed on nutrients in the water. Despite Charnia's fern-like appearance, it is not a photosynthetic plant or alga because the nature of the fossilbeds where specimens have been found implies that it originally lived in deep water, well below the photic zone where photosynthesis can occur. "
davidw 5y ago
I think science is interesting enough in its own right that you don't need to oversell it. It is not a 'massive creature', but it's fascinating nonetheless when explained in context and without the clickbaity headline.
- loonster 5y ago
  Massive for its time. Average creature being a pinky finger (why didn't they just say a number), so about 5 cm. Half meter is 10x that. Something 10x bigger than me is not a giant, it's a titan.
  - robbedpeter 5y ago
    Moose make a great learning experience to demonstrate scale. They're goddamn huge. Nobody expects moose hugeness. Compared to the average size of creatures of the time, then, this thing would be like the biggest ever moose to us.
hutzlibu 5y ago
> There's even the suggestion that there are creatures that can't really be classified into plant or animal - it's not clear what they are at all. No plant or animal, but alive. How strange, rare and exotic ... like a mushroom? (Mushrooms are not a plant nor animal either, but if you look close enough, mushrooms are indeed strange and exotic, though)
- andrewstuart 5y ago
  You are correct. I believe there are five kingdoms of living things, and mushrooms belong to fungi. https://www.iberdrola.com/sustainability/biology-kingdoms-living-things-classification https://www.iberdrola.com/sustainability/biology-kingdoms-li... https://www.iberdrola.com/wcorp/gc/prod/en_US/comunicacion/reinos_seres_vivos_2_res/Infographic_Living_Things.jpg https://www.iberdrola.com/wcorp/gc/prod/en_US/comunicacion/r...
  - tr3ndyBEAR 5y ago
    The number of domains/kingdoms/empires/superkingdoms of living things is actually much more of a matter of debate amongst taxonomists than people realize. Taking our classification schemes as a fact about biology is confusing the map for the territory. But you are correct that mushrooms (which is the fruiting body of some types of fungi) are separate from plants (and actually more closely related to animals. They're basically animals that digest things externally instead of having a stomach to digest things internally)
    - loonster 5y ago
      We digest externally too. We just carry the outside around with us.
      - thaumasiotes 5y ago
        This shouldn't have been downvoted; external digestion, usually known as "cooking", is one of the most important features of human biology, explaining why our intestines are so short.
KingOfCoders 5y ago
There was recently a discussion here on HN about the billion years of lost sediments on earth, and one article mentioned that that the crushing of that sediments into the sea lead to much more minerals in the sea and to the Cambrian explosion.
NetOpWibby 5y ago
Fascinating, thanks for sharing!
qPM9l3XJrF 5y ago
>a very small number of basic types of animal - (perhaps only 5?) Anyone know what the ~5 types are?
- deleted 5y ago
  [deleted]
- pvaldes 5y ago
  > Five types of animals I think that he could be confusing animals with the five groups of vertebrates. IMAO, Is common in English to use animals mostly for big animals with bones and critters or bugs or "somethingsomething-fish" for everything else. If we need to choose just five, among the really, really successful types of animals (in a very broad sense) we have Mollusca, Artropoda, Cnidaria, Chordata and... lets see, I would dobt between Platyhelminths because most vertebrates are hosts of several of them, or maybe Nematoda because they are hugely influential and everywhere in the soil in large amounts. But we have also a lot of other groups: Annelida, Porifera, Echinodermata, Brachyopoda, Bryozoa, Priapulida etc... Definitely more than five big types of animals.
  - qPM9l3XJrF 5y ago
    Thanks!

ComputerGuru 5y ago

Just to add: if anyone is interested in learning more about the sudden appearance of extremely varied life, this event is called the “Cambrian explosion” and makes for some very interesting reading.

thangalin 5y ago
Cambrian Explosion is a bit of a misnomer because it leads people to think it was unique with respect to evolutionary processes. There is a push to call it the Cambrian Radiation [0]. Throughout complex life's time on Earth there have been multiple periods of rapid evolutionary development similar to the Cambrian. A blurb about the Cambrian Radiation appears in my coffee table picture book [1]. [0]: https://impacts.to/bibliography.pdf#page=41 https://impacts.to/bibliography.pdf#page=41 [1]: https://impacts.to/downloads/lowres/impacts.pdf#page=15 https://impacts.to/downloads/lowres/impacts.pdf#page=15
- mkl 5y ago
  "Radiation" sounds more unique than "explosion" to me (not an evolutionary biologist). It sounds like it means there was some unusual atomic radiation causing mutations at that time, so I think it will lead to more misunderstanding by laypeople rather than less. Why did they decide not to have multiple "explosions"? Your book looks really interesting!
  - adrian_b 5y ago
    "Radiation" is meant to suggest that the evolution advanced in many very different directions, like the rays that diverge from a point. Such "radiations" have happened every time when there was little competition either because a new place or environment was invaded or because a catastrophe had eliminated the former incumbents. The result of evolution "radiations" was that some group of animals that previously had been more or less uniform because they were adapted to a certain niche, after the "radiation" event became diversified in a large number of groups adapted to very different conditions of life and having much less resemblance between themselves than before.
    - mkl 5y ago
      Yes I understand what it means, but the word "radiation" has other much more well-known meanings, one of which directly connects to having more mutations than usual, so it's bound to be misunderstood.

holler 5y ago

> There's even the suggestion that there are creatures that can't really be classified into plant or animal - it's not clear what they are at all. Could you expand on that at all? It sounds really fascinating.

andrewstuart 5y ago
All life of course at this time is in the ocean. There's things that look like ferns, and are attached to the sea floor. But they lived at such a depth that the sunlight would not have been able to reach them so they could not have been plants. https://en.wikipedia.org/wiki/Charnia https://en.wikipedia.org/wiki/Charnia "The living organism grew on the sea floor and is believed to have fed on nutrients in the water. Despite Charnia's fern-like appearance, it is not a photosynthetic plant or alga because the nature of the fossilbeds where specimens have been found implies that it originally lived in deep water, well below the photic zone where photosynthesis can occur. "

davidw 5y ago

I think science is interesting enough in its own right that you don't need to oversell it. It is not a 'massive creature', but it's fascinating nonetheless when explained in context and without the clickbaity headline.

loonster 5y ago
Massive for its time. Average creature being a pinky finger (why didn't they just say a number), so about 5 cm. Half meter is 10x that. Something 10x bigger than me is not a giant, it's a titan.
- robbedpeter 5y ago
  Moose make a great learning experience to demonstrate scale. They're goddamn huge. Nobody expects moose hugeness. Compared to the average size of creatures of the time, then, this thing would be like the biggest ever moose to us.

hutzlibu 5y ago

> There's even the suggestion that there are creatures that can't really be classified into plant or animal - it's not clear what they are at all. No plant or animal, but alive. How strange, rare and exotic ... like a mushroom? (Mushrooms are not a plant nor animal either, but if you look close enough, mushrooms are indeed strange and exotic, though)

andrewstuart 5y ago
You are correct. I believe there are five kingdoms of living things, and mushrooms belong to fungi. https://www.iberdrola.com/sustainability/biology-kingdoms-living-things-classification https://www.iberdrola.com/sustainability/biology-kingdoms-li... https://www.iberdrola.com/wcorp/gc/prod/en_US/comunicacion/reinos_seres_vivos_2_res/Infographic_Living_Things.jpg https://www.iberdrola.com/wcorp/gc/prod/en_US/comunicacion/r...
- tr3ndyBEAR 5y ago
  The number of domains/kingdoms/empires/superkingdoms of living things is actually much more of a matter of debate amongst taxonomists than people realize. Taking our classification schemes as a fact about biology is confusing the map for the territory. But you are correct that mushrooms (which is the fruiting body of some types of fungi) are separate from plants (and actually more closely related to animals. They're basically animals that digest things externally instead of having a stomach to digest things internally)
  - loonster 5y ago
    We digest externally too. We just carry the outside around with us.
    - thaumasiotes 5y ago
      This shouldn't have been downvoted; external digestion, usually known as "cooking", is one of the most important features of human biology, explaining why our intestines are so short.

KingOfCoders 5y ago

There was recently a discussion here on HN about the billion years of lost sediments on earth, and one article mentioned that that the crushing of that sediments into the sea lead to much more minerals in the sea and to the Cambrian explosion.

NetOpWibby 5y ago

Fascinating, thanks for sharing!

qPM9l3XJrF 5y ago

>a very small number of basic types of animal - (perhaps only 5?) Anyone know what the ~5 types are?

deleted 5y ago
[deleted]
pvaldes 5y ago
> Five types of animals I think that he could be confusing animals with the five groups of vertebrates. IMAO, Is common in English to use animals mostly for big animals with bones and critters or bugs or "somethingsomething-fish" for everything else. If we need to choose just five, among the really, really successful types of animals (in a very broad sense) we have Mollusca, Artropoda, Cnidaria, Chordata and... lets see, I would dobt between Platyhelminths because most vertebrates are hosts of several of them, or maybe Nematoda because they are hugely influential and everywhere in the soil in large amounts. But we have also a lot of other groups: Annelida, Porifera, Echinodermata, Brachyopoda, Bryozoa, Priapulida etc... Definitely more than five big types of animals.
- qPM9l3XJrF 5y ago
  Thanks!