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).

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