Counting generations in one's family tree

[Eloi]

Thinking about the genetic inheritance from my earliest ancestors to me ... it occurs to me that if my family had recorded ancestors with the same care that Jews and other ancients did from the beginning of humanity, I might find many interesting details about who they were and where my relatively distant ancestors lived, before I was born on an island in the Cuban archipelago.

I could calculate with some degree of accuracy and objectivity how many generations I would have to go back in my family tree until I reached the creation of the first human couple. As far as I know no known human civilization (for all that that word entails in the sense of human development) has been dated with certainty before the year of the Biblical creation of Adam and Eve, around 4025 BC.

Evolutionist friend, tell me: what would be the number of generations that you would have to go back in your family tree, until your ancestor is no longer an intelligent human being but a simple ape that can be considered as a common animal?

[DrNoGods]

[Replying to Eloi in post #20]

Again:
Quote: "The fossils were previously thought to have dated to 1–2 million years ago[6][8][9][3]"

Again ... the key phrase there is previously thought. That does not refer to actual dating results on the fossils.

The fossils were OFFICIALLY DATED 1-2 millions years.

No they weren't, and none of the 4 references you listed state that (did you actually read them?).

Reference 6:
"However, since the age of the fossils remains unclear, one of the next challenges will be to date the remains to provide more information about the early evolution of humans and their close relatives."
No dating results are contained in this paper.

Reference 8:
"According to the dated Bayesian analysis, the most likely age for H. naledi is 912 ka."
This is an estimate based on (as the article says ) a Bayesian analysis approach. There was no actual dating performed on the fossils (eg. ratiometric, or otherwise).

Reference 9:
"As yet no secure date for this extraordinary material has been obtained, and the relationship of this species to other Plio-Pleistocene taxa has been greatly debated in the media. Here I report results of morphometric analyses that may facilitate an assessment of the age and affinities of crania attributed to H. naledi."
Again, no actual fossil dating results are presented. The author did an analysis based on cranial volumes and came up with a guess.

Reference 3:
"We were able to report that we are working on determining the geological age of the fossil deposit, applying techniques that can be used to date the site’s flowstones (sheetlike formations of calcite that grow where water flows down walls or floors in caves)."
No dates (even guessed at) are given in this article.

So no, the fossils were not "OFFICIALLY DATED 1-2 millions years." Those dates were guesses PRIOR to the availability of any actual dating results based on various comparisions and inferences because that's what scientists do ...try to explain things based on the best data and analysis that is available, and refine as needed when new information, tools, etc. become available.

The techniques to calculate the age of fossils can be various. Some of those techniques are speculative.

And?

[Eloi]

Do you know why the second reference mentions “Bayesian phylogenetic methods“?

Read this from the fourth reference:

We planned a half-hour question-and-answer session at the end of the symposium session, facilitated by team members Steven E. Churchill of Duke University and Darryl J. de Ruiter of Texas A&M University. It was one of the most interesting periods of open discussion I’ve seen at a professional conference. People offered a broad range of perspectives about the H. naledi fossils, the site, and our open-access philosophy regarding the data. But during the discussion, one question was posed above all others: How will we be able to figure out the age of the fossils?


The H. naledi analysis was unique in recent paleoanthropology for proceeding on the basis of anatomy alone, without knowing the age of the fossil deposit. This approach was taken partly out of necessity, because of the lack of many of the usual hints regarding geological age. But also, we recognized that the placement of a species into the family tree of organisms, or its phylogenetic position, is one that depends on the pattern of branching in the tree and not the age of the branches. H. naledi’s anatomical mosaic makes the age determination particularly difficult—did it acquire derived traits early or preserve primitive traits late?

Still, the question of its age is a fascinating one that will test hypotheses about the environmental setting of H. naledi and answer the question of whether it coexisted with any other hominin species. We were able to report that we are working on determining the geological age of the fossil deposit, applying techniques that can be used to date the site’s flowstones (sheetlike formations of calcite that grow where water flows down walls or floors in caves). We are also using some destructive mechanisms to examine the bones and teeth themselves. Developing the chronology is a difficult undertaking, and we are committed to being cautious as we proceed.

https://web.archive.org/web/20170516082 ... omo-naledi

Bayesian analysis,

a method of statistical inference (named for English mathematician Thomas Bayes) that allows one to combine prior information about a population parameter with evidence from information contained in a sample to guide the statistical inference process. A prior probability distribution for a parameter of interest is specified first. The evidence is then obtained and combined through an application of Bayes’s theorem to provide a posterior probability distribution for the parameter. The posterior distribution provides the basis for statistical inferences concerning the parameter.

https://www.britannica.com/science/Bayesian-analysis

Let me tell you a secret: You can't manipulate everyone.

[DrNoGods]

[Replying to Eloi in post #22]

Do you know why the second reference mentions “Bayesian phylogenetic methods“?

Yes ... they describe it up front in the paper.

"We used a large supermatrix of craniodental characters for both early and late hominin species and Bayesian phylogenetic techniques to carry out three analyses. First, we performed a dated Bayesian analysis to generate estimates of the evolutionary relationships of fossil hominins including H. naledi. Then we employed Bayes factor tests to compare the strength of support for hypotheses about the relationships of H. naledi suggested by the best-estimate trees. Lastly, we carried out a resampling analysis to assess the accuracy of the age estimate for H. naledi yielded by the dated Bayesian analysis."


That should have made it very clear that they did not actually date the fossils directly, or even try to. They used a statistical approach to try and guess the best age for the fossils because no actual dating results were available.

Let me tell you a secret: You can't manipulate everyone.

No one is trying to manipulate anyone. This isn't some conspiracy theory where the evolutionists are trying to brainwash the religious into thinking they evolved from apes. A bunch of fossils were found in a cave that had surprising characteristics. People wanted to know what they were, how old they were, where they fit into the Homo line, etc. (ie. exactly the same as for all fossil finds that might provide more information on how humans evolved ... which is how we actually did get here).

It is piecing together all of the fossil finds to date that progressively yields a more complete puzzle on human evolution, and it gets refined as the years go by and more fossils are found, more genetic work is done, etc. And all of it confirms that modern humans did evolve from an ape ancestor and we are just part of that sequence. Most people today realize this is how it actually happened, and not via some magical "creation" event a measly 6000 years ago. Only a tiny number of people still buy into that impossible story.

[Eloi]

The theory of evolution is full of "scientists" guessing.

PS: if we are talking about "science", why do you make so much reference here to the subject of the Bible and Jehovah's Witnesses? Are you treating us like the competition? Or are you giving us credit for reasoning correctly about science issues?

[brunumb]

The theory of evolution is full of "scientists" guessing.

PS: if we are talking about "science", why do you make so much reference here to the subject of the Bible and Jehovah's Witnesses? Are you treating us like the competition? Or are you giving us credit for reasoning correctly about science issues?

If you are basing the age of human beings on the Bible, what supporting evidence for its claims can you provide?

[DrNoGods]

[Replying to Eloi in post #24]

The theory of evolution is full of "scientists" guessing.

Clearly not. It would never have reached the the status of formal scientific theory (which it is) if it was all guesswork over the last 150 years.

PS: if we are talking about "science", why do you make so much reference here to the subject of the Bible and Jehovah's Witnesses? Are you treating us like the competition? Or are you giving us credit for reasoning correctly about science issues?

Because these sources are evidently where you are getting the erroneous idea that humans simply appeared on the scene, fully formed, some 6000 years ago rather than evolving from prior ape ancestors as shown by the fossil record and genetics work.

The bible and JWs are certainly no competition to real science though as far as getting at the truth of things. Very few people these days take the old bible stories as literal truth because they are so outlandish and easily debunked. Much better to look at them as allegory, or simply as myths, from a time when scientific knowledge was orders of magnitude below what is understood today. Most people no longer believe the Earth is flat, or stationary, or the center of the universe, or that a god pulls the sun across the sky or causes volcanoes to erupt because he's upset with the sacrifices. But, unfortunately, there are some who still buy into this sort of nonsense.

[Purple Knight]

They were dated BEFORE 1-2 millions years, and later 335-236 thousands, only AFTER 4 YEARS!!!!!!!
Isn't it funny what people have to swallow from these guys who call themselves "scientists"? In fact, the "homo naledi"s were still jumping from branch to branch, according to them, but they were hominids (semi-human) at the same time, also according to them.

I agree that after such drastic revisions, the obligation of trust is not there.

A few days ago I saw a video of a man who has transformed his entire body. He doesn't look human. The most interesting thing is that he says that he does not consider himself human but an alien ... like you who consider yourselves animals.

The ancient apes, poor guys ... they can't decide by themselves to be what they really are. Some today wanna make them "humans" by force.

Technically speaking, whatever can breed with a species and make fertile offspring, is itself a member of that species. Nobody is forced to accept this definition, however. It's just a very useful definition. When we talk about cats, and wanting to obtain one, what we must be concerned with is the breeding pool of cats. If you have one, and want to make more, you need another of the same kind as you already have, meaning, the same species, meaning, it will successfully combine with the one you have. If you start with a housecat, and I give you a dog, or an orangutan, it will not be useful to you. If I give you a caracal or a serval, you might struggle immensely, but still ultimately make due (...cats might secretly all be one species). And thus the usefulness of the definition.

[DrNoGods]

[Replying to Purple Knight in post #27]

I agree that after such drastic revisions, the obligation of trust is not there.

But there were no revisions. There were initial guesses at an age range made using various approaches because no direct dating results for the fossils were available (it took 4 years to get those). The initial guesses proved to be wrong once it was possible to directly date teeth and sediments, but the direct dating results were not revisions to prior dating results ... they were the first direct dating results and have not been revised since 2017.

Wikipedia
"In 2017, the Dinaledi remains were dated to 335,000–236,000 years ago in the Middle Pleistocene, using electron spin resonance (ESR) and uranium–thorium (U-Th) dating on three teeth, and U-Th and paleomagnetic dating of the sediments they were deposited in. The fossils were previously thought to have dated to 1–2 million years ago because no similarly small-brained hominins had previously been known from such a recent date in Africa."

[Purple Knight]

But there were no revisions. There were initial guesses at an age range made using various approaches because no direct dating results for the fossils were available (it took 4 years to get those). The initial guesses proved to be wrong once it was possible to directly date teeth and sediments, but the direct dating results were not revisions to prior dating results ... they were the first direct dating results and have not been revised since 2017.

They are guesses. They're still guesses. They're just much better guesses.

Especially if they date the teeth, bones, and sediments, and get a close match on all.

[DrNoGods]

[Replying to Purple Knight in post #29]

They are guesses. They're still guesses. They're just much better guesses.

Especially if they date the teeth, bones, and sediments, and get a close match on all.

Direct dating via the methods used has uncertainty (hence the 100K range given), but is not "guessing." The prior estimates were much more in the "guess" category, based on what turned out to be wrong assumptions (ie. that such small cranial volumes, and arboreal features, implied much older ages as this had not been seen before).

This was a hugely important and large find, so of course everyone wanted to know how old they were and what it meant for adding pieces to the human evolution puzzle. While waiting for direct dating results, people tried to make estimates using other approaches and those turned out to be wrong. It was presented in post 17 as if the scientists involved in all of this were knuckleheads who actually dated the fossils to 1-2 million years, then willy-nilly changed their minds to a much more recent age range. That is not at all what happened.