On 28.4.2021. 16:47, Mario Petrinovic wrote:
> On 28.4.2021. 15:04, John Harshman wrote:
>> On 4/28/21 5:41 AM, Mario Petrinovic wrote:
>>> On 28.4.2021. 2:05, nyik...@gmail.com wrote:
>>>> Hi, Mario!  I hope you didn't give up waiting around for me and are
>>>> still reading s.b.p.
>>>> I didn't emerge anywhere on Usenet for three and a half months of
>>>> 2021, and then
>>>> I put in a few sporadic posts to talk.origins. But it's close to a
>>>> week since I was there last,
>>>> and this is my first post of 2021 to sci.bio.paleontology.
>>>>
>>>> On Saturday, April 3, 2021 at 2:16:47 PM UTC-4, Mario Petrinovic wrote:
>>>>> On 3.4.2021. 15:42, Oxyaena wrote:
>>>>>> On 4/2/2021 11:09 PM, John Harshman wrote:
>>>>>>> On 4/2/21 6:06 PM, Mario Petrinovic wrote:
>>>>>>>> Just like I said it here, so many months (or could it be,
>>>>>>>> years?) ago.
>>>>>>>> So many new scientific ideas originated in my head, but
>>>>>>>> nobody, ever, gives me any credit for this (except for few people).
>>>>
>>>> Fortunately, I am well enough known in several branches of
>>>> mathematics not to
>>>> be concerned about getting credit for general ideas, anywhere. For
>>>> instance, I thought
>>>> I had coined the term "mega-evolution" to denote evolution that
>>>> produces new orders,
>>>> classes, or phyla of animals, plants, or fungi.
>>>>
>>>> That makes it the most interesting kind of macroevolution, which
>>>> some take to
>>>> mean "speciation".
>>>>
>>>> Anyway, Hemidactylus surprised me by posting a once-in-a-blue moon
>>>> (for him)
>>>> on-topic post in talk.origins, telling me that George Gaylord
>>>> Simpson had coined
>>>> the word long ago -- perhaps even before I was born.  But I didn't
>>>> mind.
>>>> In fact, I was sort of relieved to learn that a world-class
>>>> evolutionary theorist
>>>> had come up with the term, but I'll save the reason why for another
>>>> post.
>>>>
>>>>>>>> https://www.bbc.com/news/science-environment-56617409
>>>>>>>>
>>>>>>> But that isn't what the story says. You have it exactly backwards.
>>>>
>>>> Harshman often hides behind the claim that he has a bad memory,
>>>> but here he shows that he remembers something I didn't. You
>>>> said nothing in your OP  that could be construed as backwards
>>>> from the following.
>>>>
>>>>>>> The story says that the asteroid impact caused dinosaur
>>>>>>> extinction, and
>>>>>>> the absence of dinosaurs could have resulted in a change in the
>>>>>>> character of Amazon forests.
>>>>
>>>> It's some of both, but the article definitely leans in John's
>>>> direction. But, to use a colloquialism,
>>>> that has diddly-squat to do with the ACTUAL relative strength of the
>>>> two directions.
>>>> Problem is, I may be missing out on some fine points of the opposite
>>>> direction that you had, Mario.
>>>>
>>>>
>>>> Now Oxyaena puts in her two cents' worth:
>>>>
>>>>>> Well, I mean, the extinction *did* result in a turnover of flora and
>>>>>> fauna, and for a not-insignificant period of time there were no large
>>>>>> herbivores to affect the Amazon's plant life, and by extension, the
>>>>>> world's. Just because biodiversity will invariably recover after a
>>>>>> mass
>>>>>> extinction doesn't mean that said biodiversity will be of the same
>>>>>> character as it was prior to the extinction event in question.
>>>>
>>>> Harshman has been showing less and less interest in exploring
>>>> scientific
>>>> issues, so he hasn't replied to either Oxyaena or to you.
>>>>
>>>> As for Oxyaena, she started her own new thread on the extinction less
>>>> than 15 minutes after posting the above, but Harshman' never showed
>>>> interest in it. In fact, nobody has posted there after that OP of hers.
>>>> Not even her comrade-in-arms, Erik Simpson.
>>>>
>>>>> It should have been (of the same character). I discussed this already
>>>>> (with Peter, I believe). There is no reason for herbivores to
>>>>> evolve out
>>>>> of mammals, and it took 10 million years for mammals to acquire that
>>>>> niche, if you already had seeds of dinosaur herbivores alive. Why
>>>>> would
>>>>> life wait for 10 million years for mammals to adapt for that, dinos
>>>>> were
>>>>> already adapted?
>>>>
>>>> There actually were mammalian herbivores that survived the K-T
>>>> extinction,
>>>> among the Multituberculata and a number of other now-extinct
>>>> branches of
>>>> mammalia.
>>>>
>>>> But if you are thinking of *large* herbivores, yes, I believe the
>>>> first really
>>>> large ones were among the Pantodonta, and it took them 10 million
>>>> years to get to that point.
>>>>
>>>>
>>>>> No, this was a system failure. Failure of the character that prevented
>>>>> plants which couldn't reach the sunlight to grow, and this is what,
>>>>> actually, killed *all* the dinosaurs, without leaving pockets of them
>>>>> alive, here or there. And that happened when avian dinosaurs (or, I
>>>>> would say, dinosaurs which had bills) survived.
>>>>
>>>> You ought to be a little more specific here: "survived" doesn't hit
>>>> the spot.
>>>> "Evolved into more fearsome forms" might be closer to what you had
>>>> in mind, Mario.
>>>>
>>>> There are other problems with what you wrote in the preceding
>>>> sentence, but I need to get
>>>> back to grading the last test I've given ca. 75 students, so I'll
>>>> tackle them another day, hopefully tomorrow.
>>>
>>>          Thanks, Peter.
>>>          Well, so far I don't see a problem here. They did survive,
>>> and they did evolve, everybody who survives evolves. The point is,
>>> they didn't go extinct. You don't go extinct without a reason.
>>> Herbivores of mammalian type didn't go extinct (as you mentioned),
>>> large herbivores of mammalian type didn't exist (as far as I can
>>> grasp), or, at least, didn't exist in areas where they emerged 10 my
>>> later. The fact is that all fern eaters of a dino type (and their
>>> predators) went extinct, while not all dinos went extinct. So, the
>>> problem was in eating ferns.
>>>          The fact that ecology changed is in tune with that. The
>>> question was, did ecology change because of dinos went extinct? There
>>> is no reason for just a specific type of dinos to go extinct, or, at
>>> least, nobody mentioned it anywhere, nobody knows for the reason,
>>> there is no theory about that reason, there is no idea about the
>>> reason, there is no just-so story about the reason, absolutely
>>> nothing, there is only a "possibility" that this could have happened
>>> (but no reason for that). I mean, there is a possibility that life on
>>> Earth was started by aliens, but, hey, are we at that level of
>>> reasoning? Or, is science on that level of reasoning? If it shouldn't
>>> be, then why it behaves like they are on that level?
>>>          On the other hand, there could be some reason for ecology to
>>> change. My *idea* is that plants that crave for sunlight already
>>> evolved at poles (definitely there is some logic in it). The impact
>>> created the lack of sunlight (there were already some theories about
>>> that), so the plants that are able to collect more sunlight prevailed
>>> over ferns. This is one simple and logical explanation for this
>>> mechanism. For the mechanism that only some types of dinosaurs went
>>> extinct there is no explanation of mechanism.
>>>          I believe that I am clear enough.
>>>
>>>> How is that group coming along?
>>>
>>>          Ah, thanks, :). Besides me there are two more members, Daud
>>> Deden and Marc Verhaegen, but there is no discussion going on at all.
>>> So far I am happy, this is a good start, :) .
>>>
>> One problem with your theory is the post-Cretaceous "fern spike". For
>> a short time after the impact ferns dominated the terrestrial
>> vegetation. Another problem is that the poles get much less sunlight
>> than the tropics, so plants that "crave for" sunlight would be less
>> likely to be located there than elsewhere. And third, the post-K-T
>> lack of sunlight could have lasted a couple of years at most. Finally,
>> you have no evidence that herbivorous dinosaurs were dependent on
>> ferns, which seems very unlikely on its face.
>>
>> There also are theories about why the dinosaurs and not birds or
>> mammals went extinct. They were large. If, as is commonly thought,
>> extinctions mostly happened as a result of radiant heat from the sky
>> resulting from the re-entry of small ejecta, big animals would be less
>> able to hide under rocks and in burrows than small ones. And there you
>> have the filter to explain the extinction.
>
>         Thanks John.
>         "Fern spike", I'll have to examine this.
>         Not necessarily "crave" for sunlight, but definitely being
> better in scooping the sunlight. Like hemoglobin in blood, which
> extracts oxygen. If oxygen levels fall, obviously the animals adapted to
> low levels will thrive.
>         A couple of years could be enough.
>         I believe the teeth of dinosaurs were adapted just to strip
> ferns (but I am not sure about it).

Yes, "Fern spike" actually isn't a problem. It isn't a problem in
ferns, but actually, in trees above ferns. So, after the land cleared
up, because of the event, ferns started to cover the land rapidly. This
is a "Fern spike". But, what follows is the growth of different types of
trees above those ferns, which killed the ferns, fern eaters, and their
predators.

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