Convergent evolution? How much convergence?

SpaceNut · 2019-02-16 14:25:06

It sure is hard to find topics sometimes that one has been posting within...

Starting with the bacterial single cell to where we are now. One could say that we have had many cradles of life which have been caused by the environmental changes which has caused life to adapt or die.

Earth first origins project seeks to replicate the cradle of life

SpaceNut · 2019-04-13 19:53:21

Very hard topic to find but here is my post to it.
New Study Says That Life May Have Started in Ponds; The new MIT study discusses how a 10 centimeter pond would be the ample environment for the creation of life.

Nitrogen is the harbinger of life. In the shallow ponds mentioned in the study, nitrogen takes the form of nitrogenous oxides. Within these ponds, the substance would have an easier opportunity to accumulate the compounds to bring about life, compared to the much larger and deeper oceans. So high enough concentration of all the necessary ingredients needed to create life.

louis · 2019-04-14 05:33:47

Good to know!

SpaceNut wrote:

Very hard topic to find but here is my post to it.
New Study Says That Life May Have Started in Ponds; The new MIT study discusses how a 10 centimeter pond would be the ample environment for the creation of life.
Nitrogen is the harbinger of life. In the shallow ponds mentioned in the study, nitrogen takes the form of nitrogenous oxides. Within these ponds, the substance would have an easier opportunity to accumulate the compounds to bring about life, compared to the much larger and deeper oceans. So high enough concentration of all the necessary ingredients needed to create life.

SpaceNut · 2020-04-04 17:24:02

repost as it relates to this topic:

Void wrote:

I lied. I am going to go wordy on you.
They say that an asteroid struck the Earth ~65??? million years ago. Among the survivors, birds, and mammals. I think most likely the survivors of such an evet would be from the Alpine areas where cold tolerance was a requirement for life. Other protective methods such as burrows, and cliff dwelling might also have helped. Just a speculation.
Where I am going with this is "Methods of procreation". (Not an X rated event). Procreation indicates that your offspring survive into the future. Birds and Mammals present various examples which seem to have success for those not yet extinct.
I think that if Mammals were not so able to kill the offspring of nested birds, and if birds therefore were not required to fly and nest in protected locations, then birds could have had big brains, and perhaps been very advanced in mind power. Many birds have mutual participation in child rearing. Many mammals do not. Some humans are like binary bird pairs in making a family for protection of the offspring. Some are less so.
The differences are something like say a bear. In general the male bears responsibility in life is to be a big bad bear. Then momma bear might be more likely to accept him, because her offspring many also be big bad bears. If he has anything to do with cub bears, it is likely to be him killing them. They failed the test for big bad bearhood.
But nesting creatures such as many birds and humans , are not as much like that. But there is a tension between nesting participation from males of humans, and being big and bad. I feel that many females do quite well with nesting instinct but not all of them. Human males in my opinion are some of each. Nesters, and to not be profane (Big Bad). And I don't use the word for rectum that is profane, quite.
Going to Mars to set up a descendent or an inheritor culture, is a form of procreation. And as for the predicament of birds, weight matters if you are going to fly there. Good binary bird methods, not big bad bears.
So, unless you are in bird school and will be punished for cheating, all the cheat methods against the malice of the universe are quite welcome for me and those like me.
I will return, I hope with Mule Method(s). Need a break.

SpaceNut · 2020-04-04 17:26:40

The life question of much smaller organisms being transferred seems to be very probable but not sure how many more cells of larger species transfered would be the question for did they make it in either direction. I do agree that larger life would rebound for Mars or for earth has been shown possible but for the travel its questionable..

SpaceNut · 2020-05-13 07:37:04

Trying to understand earths past is hard when A billion years is missing from the geologic record

"There are unconformities all through the rock record," A leading thought is that glaciers scoured away kilometers of rock around 720 to 635 million years ago, during a time known as Snowball Earth, when the planet was completely covered by ice. This hypothesis even has the benefit of helping to explain the rapid emergence of complex organisms shortly thereafter, in the Cambrian explosion, since all this eroded material could have seeded the oceans with tremendous amounts of nutrients.
technique called thermochronology. A few kilometers below the Earth's surface, the temperature begins to rise as you get closer to the planet's hot mantle. This creates a temperature gradient of roughly 50 degrees Celsius for every kilometer of depth. And this temperature regime can become imprinted in certain minerals.
As certain radioactive elements in rocks break down, Helium-4 is produced. In fact helium is constantly being generated, but the fraction retained in different minerals is a function of temperature. As a result, scientists can use the ratio of helium to thorium and uranium in certain minerals as a paleo-thermometer.
The team took samples from granite just below the boundary of the Great Unconformity at Pikes Peak in Colorado. They extracted grains of a particularly resilient mineral, zircon, from the stone and analyzed the radio nucleotides of helium contained inside. The technique revealed that several kilometers of rock had been eroded from above this granite between 1,000 and 720 million years ago.

Sounds like the theory is close enough..

Void · 2020-05-13 10:05:06

Spacenut, please forgive me for intruding.

But that is a lot of rock to grind off, and to me, it means that the ice elevations must have been uneven.

Which might support my ideas about the so called "Snowball Earth" notions.

So, to make it quick, in such a world, I have greater suspicion that strong glaciation will happen at high altitudes, and high latitudes. So, snow and ice will collect there.

But what about the low latitude ocean floors?

So, if the ice were on the Ocean floors, that seems to me to be a situation where glaciation is going to be weaker.

Here is a map of the ocean floors:
https://gizmodo.com/heres-the-most-comp … 1750109568

As in our more recent ice age, I would expect the sea level of the oceans to drop. For the snowball Earth it might be all the way down the Abyssal Plane.

https://en.wikipedia.org/wiki/Abyssal_plain

So, then as water piled up as ice on the continents, and high latitudes, for the low latitude abyssal plane(s), we could expect a very thick troposphere. And so a massive greenhouse effect on the ocean floor. And that would provide the ice to go onto the continents, and the space for the glaciers to flow downward.

This is only one reason, I do not hold fast to the standard notion of a habitable zone around a star.

Sorry if I am a painful item in your anatomy.

Done.

Last edited by Void (2020-05-13 12:26:26)

louis · 2020-05-13 11:49:57

Thanks for that Spacenut - interesting...I wasn't aware of the missing record, though I had heard of Snowball Earth.

SpaceNut wrote:

Trying to understand earths past is hard when A billion years is missing from the geologic record
"There are unconformities all through the rock record," A leading thought is that glaciers scoured away kilometers of rock around 720 to 635 million years ago, during a time known as Snowball Earth, when the planet was completely covered by ice. This hypothesis even has the benefit of helping to explain the rapid emergence of complex organisms shortly thereafter, in the Cambrian explosion, since all this eroded material could have seeded the oceans with tremendous amounts of nutrients.
technique called thermochronology. A few kilometers below the Earth's surface, the temperature begins to rise as you get closer to the planet's hot mantle. This creates a temperature gradient of roughly 50 degrees Celsius for every kilometer of depth. And this temperature regime can become imprinted in certain minerals.
As certain radioactive elements in rocks break down, Helium-4 is produced. In fact helium is constantly being generated, but the fraction retained in different minerals is a function of temperature. As a result, scientists can use the ratio of helium to thorium and uranium in certain minerals as a paleo-thermometer.
The team took samples from granite just below the boundary of the Great Unconformity at Pikes Peak in Colorado. They extracted grains of a particularly resilient mineral, zircon, from the stone and analyzed the radio nucleotides of helium contained inside. The technique revealed that several kilometers of rock had been eroded from above this granite between 1,000 and 720 million years ago.
Sounds like the theory is close enough..

Void · 2020-05-13 12:30:53

Hay Spacenut and Louis,

It is not my joy to annoy.

http://www.revimage.org/life-on-earth-7 … years-ago/

If we comprehend where the glaciers were likely to have been that would have removed rock layers, can we calculate where the glacial deposits may have ended up. Then it might be possible to recover some information about what was removed. That is, where they were not then further modified by some other process.

And to be a real jerk, here is what our last ice age did, turning sea floor into "Land". I think that a snowball Earth would have been much more extreme.

https://iceagenow.com/Sea_Level_During_Last_Ice_Age.htm

An interesting factor in all of this is if you had an atmosphere overlying what we think should be ocean floor, say 5000 feet, you can say km, I don't care. OK, km....1.524

Then what about the spectrum of light that gets to where the plants might live Lichens or Vascular?

Here is a fun fact!

https://www.popsugar.com/beauty/photo-g … et-Sunburn

So, if I am even approximately correct, the seafloor habitats that I presume might have existed, would have been vastly kinder to life than what we have now.

I don't mind if you need to put me in my place, I just would like to know why I might be wrong?

It's cool, I really don't mind, as long as the arguments are rational. (And of course I am being arrogant, presuming I understand what is rational).

Done.

Last edited by Void (2020-05-13 12:39:28)

SpaceNut · 2020-05-13 12:37:50

I agree buried even deeper beneath even the last ice age for sure.

Void · 2020-05-13 12:42:01

Yes of course Spacenut. I feel the urge to bow to you but I don't know what is your proper title.

louis · 2020-05-13 14:38:16

Doesn't stuff on the ocean beds get conveyed back into the mantle (plate techtonics) unlike the continents sitting on the plates? (Or maybe I should say, more quickly)

Void wrote:

Hay Spacenut and Louis,
It is not my joy to annoy.
http://www.revimage.org/life-on-earth-7 … years-ago/
If we comprehend where the glaciers were likely to have been that would have removed rock layers, can we calculate where the glacial deposits may have ended up. Then it might be possible to recover some information about what was removed. That is, where they were not then further modified by some other process.
And to be a real jerk, here is what our last ice age did, turning sea floor into "Land". I think that a snowball Earth would have been much more extreme.
https://iceagenow.com/Sea_Level_During_Last_Ice_Age.htm
An interesting factor in all of this is if you had an atmosphere overlying what we think should be ocean floor, say 5000 feet, you can say km, I don't care. OK, km....1.524
Then what about the spectrum of light that gets to where the plants might live Lichens or Vascular?
Here is a fun fact!
https://www.popsugar.com/beauty/photo-g … et-Sunburn
So, if I am even approximately correct, the seafloor habitats that I presume might have existed, would have been vastly kinder to life than what we have now.
I don't mind if you need to put me in my place, I just would like to know why I might be wrong?
It's cool, I really don't mind, as long as the arguments are rational. (And of course I am being arrogant, presuming I understand what is rational).
Done.

Last edited by louis (2020-05-13 14:51:24)

Void · 2020-05-13 17:41:52

And so does that mean we should give up and not look?

louis · 2020-05-13 18:08:56

No quite the reverse! - look for it before it disappears!

Void wrote:

And so does that mean we should give up and not look?

SpaceNut · 2020-05-13 18:13:29

Like grains through the hour glass these are the days of our lives....

elderflower · 2020-05-23 14:32:46

Not all of the deep ocean floor ends up subducted into the mantle. Occasionally bits of it get shoved up or welded onto bits of continental crust. These are formations called ophiolites. There is one in Oman, another forms the Lizard peninsula in Cornwall and there is one in Cyprus, which was the main source of copper in ancient times, hence the name of the island- or maybe the other way about. Maybe one of these could have been formed from crust including rocks from before the snowball Earth episodes.

Void · 2020-05-23 18:26:47

Nice!

SpaceNut · 2020-07-29 17:39:26

Scientists pull living microbes, possibly 100 million years old, from beneath the sea

Deep sea microbes dormant for 100 million years are hungry and ready to multiply by University of Rhode Island Magnified image showing microbes revived

SpaceNut · 2020-08-26 20:10:07

We may not have dna from mars or even a confirmed fossil just yet but Bacteria could survive travel between Earth and Mars when forming aggregates

https://dx.doi.org/10.3389/fmicb.2020.02050

SpaceNut · 2020-12-11 20:19:02

Mass extinctions of life on Earth appear to follow a regular pattern, a new study suggests.

BB1bQUxw.img?h=857&w=799&m=6&q=60&o=f&l=f

In fact, widespread die-offs of land-dwelling animals – which include amphibians, reptiles, mammals and birds – follow a cycle of about 27 million years, the study reports. Paleontologists had previously discovered that similar mass extinctions of marine life, in which up to 90% of species disappeared, were not random events, but seemed to come in a 26-million-year cycle. The study said that the impacts can create conditions that would stress and potentially kill off land and marine life, including widespread dark and cold, wildfires, acid rain and ozone depletion. The most infamous asteroid strike we know of is the one that killed off the dinosaurs some 66 million years ago, which overall wiped out 70% of the species on Earth.

Wonder where we are on the time cycle of these impacts since the last one....

SpaceNut · 2021-02-08 21:10:36

Is the verdict in Some Scientists Believe All Life Started on Mars BB1dvO6y.img?h=400&w=799&m=6&q=60&o=f&l=f

Persaverence is landing in a few weeks and its hope that it will "find DNA scraps on samples of material from Mars."

louis · 2021-02-09 08:22:33

Hmmm...now they tell us? When they've spent the past 50 years playing down the possibility of life on Mars...have recent robot missions found evidence then?

SpaceNut wrote:

Is the verdict in Some Scientists Believe All Life Started on Marshttps://img-s-msn-com.akamaized.net/tenant/amp/entityid/BB1dvO6y.img?h=400&w=799&m=6&q=60&o=f&l=f
Persaverence is landing in a few weeks and its hope that it will "find DNA scraps on samples of material from Mars."

tahanson43206 · 2021-02-13 16:22:27

For SpaceNut ... you may have already posted this ...

https://www.salon.com/2021/02/07/why-so … -to-earth/

"To me the idea that it all started on Earth, and every single solar system has their own little evolution of life happening, and they're all independent — it just seems kind of dumb," Ruvkun said. "It's so much more explanatory to say 'no, it's spreading, it's spreading all across the universe, and we caught it too, it didn't start here," he added. "And in this moment during the pandemic — what a great moment to pitch the idea. Maybe people will finally believe it."
Nicole Karlis
Nicole Karlis is a staff writer at Salon. She covers health, science, tech and gender politics. Tweet her @nicolekarlis.

A relative sent a link to this article, and if you don't already have it it might be worth adding to the collection.

(th)

SpaceNut · 2021-02-15 10:15:33

Scientists accidentally found life under 3,000 feet of ice in Antarctica. 'Never in a million years' would they have expected it, the lead scientist said.

The previous theory was that life couldn't exist in such extremity: no food, freezing temperatures, and complete darkness.
The creatures were found attached to a boulder in the frigid seas under the Filchner-Ronne ice shelf. Experts from the British Antarctica Survey drilled through 2,860 feet of ice, then another 1,549 feet of water to make the discovery.

SpaceNut · 2021-03-30 17:48:21

https://www.spacedaily.com/m/reports/Ph … f_999.html

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#26 2019-02-16 14:25:06

Re: Convergent evolution? How much convergence?

#27 2019-04-13 19:53:21

Re: Convergent evolution? How much convergence?

#28 2019-04-14 05:33:47

Re: Convergent evolution? How much convergence?

#29 2020-04-04 17:24:02

Re: Convergent evolution? How much convergence?

#30 2020-04-04 17:26:40

Re: Convergent evolution? How much convergence?

#31 2020-05-13 07:37:04

Re: Convergent evolution? How much convergence?

#32 2020-05-13 10:05:06

Re: Convergent evolution? How much convergence?

#33 2020-05-13 11:49:57

Re: Convergent evolution? How much convergence?

#34 2020-05-13 12:30:53

Re: Convergent evolution? How much convergence?

#35 2020-05-13 12:37:50

Re: Convergent evolution? How much convergence?

#36 2020-05-13 12:42:01

Re: Convergent evolution? How much convergence?

#37 2020-05-13 14:38:16

Re: Convergent evolution? How much convergence?

#38 2020-05-13 17:41:52

Re: Convergent evolution? How much convergence?

#39 2020-05-13 18:08:56

Re: Convergent evolution? How much convergence?

#40 2020-05-13 18:13:29

Re: Convergent evolution? How much convergence?

#41 2020-05-23 14:32:46

Re: Convergent evolution? How much convergence?

#42 2020-05-23 18:26:47

Re: Convergent evolution? How much convergence?

#43 2020-07-29 17:39:26

Re: Convergent evolution? How much convergence?

#44 2020-08-26 20:10:07

Re: Convergent evolution? How much convergence?

#45 2020-12-11 20:19:02

Re: Convergent evolution? How much convergence?

#46 2021-02-08 21:10:36

Re: Convergent evolution? How much convergence?

#47 2021-02-09 08:22:33

Re: Convergent evolution? How much convergence?

#48 2021-02-13 16:22:27

Re: Convergent evolution? How much convergence?

#49 2021-02-15 10:15:33

Re: Convergent evolution? How much convergence?

#50 2021-03-30 17:48:21

Re: Convergent evolution? How much convergence?

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