Going extinct may not be as easy as we imagine

[Skybird]

https://www-nzz-ch.translate.goog/fo...x_tr_hist=true

[mapuc]

If you thinking in one disaster only, it wouldn't be as easy as we think to erase the Human totally.

Who says it will only be one disaster- If we look at our religious books they describe several disaster after each other. Even here there will be survivors among the humans.

There's one disaster in which there will be no survivor-That is if we haven't started to expand our livings to other planets. What I'm talking about is when the sun grow and eat earth.

Another question is.

What about our own development? Right now we are called Homo Sapiens Sapiens. How would the next step be like ? And would they outrun the Homo Sapiens Sapiens or will there be survivors ?
Even here-When the first Homo Sapiens came they almost erased the Neanderthal from existing. From what I remember they lived among the Homo Sapiens for thousands of years before they finally got extinct.

Markus

[Rockstar]

Originally Posted by mapuc

If you thinking in one disaster only, it wouldn't be as easy as we think to erase the Human totally.

Who says it will only be one disaster- If we look at our religious books they describe several disaster after each other. Even here there will be survivors among the humans.

There's one disaster in which there will be no survivor-That is if we haven't started to expand our livings to other planets. What I'm talking about is when the sun grow and eat earth.

Another question is.

What about our own development? Right now we are called Homo Sapiens Sapiens. How would the next step be like ? And would they outrun the Homo Sapiens Sapiens or will there be survivors ?
Even here-When the first Homo Sapiens came they almost erased the Neanderthal from existing. From what I remember they lived among the Homo Sapiens for thousands of years before they finally got extinct.

Markus

I’m not so sure extinction is such a good choice to describe what happened to Neanderthals. Especially since some Homo sapiens carry Neanderthal DNA. Might better to say they were eventually bred out between 100,000 and 350,000 years ago.

As for extinction events like asteroids striking earth. Its the few hunter gathers left in the world who most likely will survive and carry on. Those who only know modern conveniences will be the first to go.

[Catfish]

Originally Posted by Skybird

https://www-nzz-ch.translate.goog/fo...x_tr_hist=true

Maybe reading Carson's "Silent Spring" might change this opinion

[Skybird]

Originally Posted by Rockstar

Might better to say they were eventually bred out between 100,000 and 350,000 years ago.

Plus they likely got outsmarted. Nutrition science and anthropology say that modern man lived in coastal regions or near rivers and had access to omega-3 fatty acid-enriched foods that made them more clever by growing their brains, while the Neanderthals had not, not to that degree at least. With that came greater intellectual adaptability to the challenges of life that saw Neanderthals more often loosing, compared to homo sapiens.

Our brains have shrunk again meanwhile, too, loosing - if I recall the numbers correctly - around 12% in size/volume over the past I think 15 thousand years or so. With the agricultural revolution 14 thousand years ago began the rise of settlement building and cultural development - at the cost of a general physical degeneration setting in. Skeleton, bone density, jawbone size, stamina, immunity and resilience to desease, brain size - it all declined. Modern Western industrially prcessed foods and carbohydrate-rich food add another acceleration to this degenerative process.

Another factor was climante chnage (:LOL), and that Neaderthals simpy followed their animal foods into the colder regions, because their preferred preys did not like warm climate, but were adapted to the colder climate zones. When the Neanderthals follwoed htem, he moved fiurtehr and further away from potential food alternatives, and when he hhd hunted down all big wildlife, he found himself stranded in regions where food then became scare and hunger started to decimate the Neanderthals.

[Ostfriese]

There are no realistic scenarios in which a single event can eliminate mankind completely.
An alien invasion followed by an eradication campaign might do the trick, but I dare say that's not within the scope of "realistic"

[Skybird]

From the article:

From the genetic diversity of our genome today, scientists have been able to reconstruct that the number of our ancestors fell to just over a thousand individuals 900,000 years ago. The cold and drought probably caused the community to shrink to the size of Kandersteg. It must have been hard times, at any rate the number of our ancestors hardly grew over the next 5000 generations. Only after 117,000 years did they spread out again.

[Rockstar]

Just an FYI, link to the article I got the above numbers from. Apparently it’s from one of many ‘new studies’ which crop up from time to time.

https://www.science.org/content/arti...r-y-chromosome

Neanderthals have long been seen as uber-masculine hunks, at least compared with their lightweight human cousins, with whom they competed for food, territory, and mates. But a new study finds Homo sapiens men essentially emasculated their brawny brethren when they mated with Neanderthal women more than 100,000 years ago. Those unions caused the modern Y chromosomes to sweep through future generations of Neanderthal boys, eventually replacing the Neanderthal Y.

The new finding may solve the decade-old mystery of why researchers have been unable to find a Neanderthal Y chromosome. Part of the problem was the dearth of DNA from men: Of the dozen Neanderthals whose DNA has been sequenced so far, most is from women, as the DNA in male Neanderthal fossils happened to be poorly preserved or contaminated with bacteria. "We began to wonder if there were any male Neanderthals," jokes Janet Kelso, a computational biologist at the Max Planck Institute for Evolutionary Anthropology and senior author of the new study.

But in a technical breakthrough, Max Planck graduate student Martin Petr designed a set of probes that used the DNA sequence from small chunks of modern men's Y chromosomes to "fish out" and bind with DNA from archaic men's Y chromosomes. The new method works because the Neanderthal and modern human chromosomes are mostly similar; the DNA probes also reel in the few basepairs that differ.

The researchers probed the fragmentary Y chromosomes of three Neanderthal men from Belgium, Spain, and Russia who lived about 38,000 to 53,000 years ago, and two male Denisovans, close cousins of Neanderthals who lived in Siberia's Denisova Cave about 46,000 to 130,000 ago. When the researchers sequenced the DNA, they got a surprise: The Neanderthal Y "looked more like modern humans' than Denisovans'," Kelso says.

This was a "puzzle," Petr says, as earlier studies showed the rest of the Neanderthal nuclear genome is a closer match for Denisovans. That suggests the two groups diverged from modern humans about 600,000 years ago. But the appearance of the unusual Y chromosome parallels another genetic takeover: Neanderthal remains dating from 38,000 to 100,000 years ago contain the maternally inherited mitochondrial DNA (mtDNA) of a modern human woman, instead of the ancient Neanderthal mtDNA found in earlier fossils. In that case, an early H. sapiens woman likely interbred with a Neanderthal man more than 220,000 years ago and their descendants carried the modern mtDNA.

The best scenario to explain the Y pattern is that early modern human men mated with Neanderthal women more than 100,000 but less than 370,000 years ago, according to the team's computational models. Their sons would have carried the modern human Y chromosome, which is paternally inherited. The modern Y then rapidly spread through their offspring to the small populations of Neanderthals in Europe and Asia, replacing the Neanderthal Y, the researchers report today in Science. Interestingly, the modern human mates were not ancestors to today's H. sapiens—but were likely part of a population that migrated early out of Africa and then went extinct. Traces of Neanderthal DNA in living humans were inherited from a separate mixing event between 50,000 and 70,000 years ago.

Researchers aren't sure exactly why the replacement happened. Natural selection may have favored the H. sapiens Y chromosome, because Neanderthals had more deleterious mutations across their genomes, Kelso says. Neanderthals had smaller populations than moderns, and small populations tend to accumulate deleterious mutations, especially on the X and Y sex chromosomes. Modern humans, with their bigger, more genetically diverse ancestral populations, may have had a genetic advantage. Another possibility is that once Neanderthals had inherited a modern human mtDNA, their cells might have favored interaction with the modern human Y, says computational biologist Adam Siepel of Cold Spring Harbor Laboratory, who was not part of the study.

The best way to test this scenario is to get DNA from early Neanderthals to see whether their Y chromosome looked more like the one in Denisovans. In the meantime, the study shows the admixture between modern humans and Neanderthals was "a defining feature of hominin history," says population geneticist Josh Akey of Princeton University, not part of the study. Not only did it give modern humans Neanderthal DNA, but it also changed Neanderthals in fundamental ways.

[mapuc]

Originally Posted by Rockstar

I’m not so sure extinction is such a good choice to describe what happened to Neanderthals. Especially since some Homo sapiens carry Neanderthal DNA. Might better to say they were eventually bred out between 100,000 and 350,000 years ago.

As for extinction events like asteroids striking earth. Its the few hunter gathers left in the world who most likely will survive and carry on. Those who only know modern conveniences will be the first to go.

You are right
What I tried to explain is that in the future a new Homo-something will arise and they will live among us, as I mentioned before
The Neanderthal lived side by side with Homo Sapiens until they were instinct. Even though they live in our DNA

Markus