> Since 2004, Dr. Hublin and his colleagues have been working through layers of rocks on a desert hillside at Jebel Irhoud.
I have so much respect for archeologists. Spending over a decade in one spot, literally on hands and knees, digging and meticulously sifting through anything that is found, is to me the epitome of dedication to a craft.
But another part of me thinks: there must be a better way!
I know that expeditions often hire bands of locals to help them dig and sift. But does anybody know, have there ever been any advances in this field to make the process go faster, or require less human toiling?
Non-invasive technologies are super-cool because we may not actually want to disturb stuff until we have the technology to do it properly. Some stuff we may never want to disturb for cultural or other reasons.
Just stressing the "other reasons" part. In some countries people actually advocate for leaving stuff like this buried for fear of corrupt gov. officials handing off what they find to smugglers.
Small observation: I worked on a dinosaur dig in Montana for 2 summers as a teen. a major problem was not identification of the bones in our case, but the fragility of the bones we were digging. Maybe 50% of our time was flaking rock away slowly with a an icepick, sweeping up the crushed rock, putting it in a bucket, and moving the crushed rock to a tailings pile. Each dedicated quadrant of the dig had its own tailings pile (1x1x1M of rock had its own pile) in case a pice of fragment was lost.
I know that low cost survey Lidar will really help, and that RTK GPS is also improving things. On larger digs, documentation with drones is also likely to produce better incremental tracking of progress. But, for this to be better, improving the actual digging is still a big unsolved problem.
EDIT: the other 50% of our time was:
40% reassembling bones with superglue in an air conditioned room. (pleasant for the temperature, but maddeningly frustrating work)
10% dig notation, journaling, discussion, planning, survey, etc.
Methodology question: why is there no mention of radiocarbon dating? It's one of our most reliable methods, it works on bones, and it doesn't have the same feel as "they used this other random technique and magically got 300,000 years old so lets go with that".
To fill in the detail: Carbon-14 has an abundance of about 1 part in 10^12, and one gram of carbon contain about 10^23 carbon atoms, so about 10^11 C-14 atoms. Every single C-14 atom will have decayed in about 200k years.
Carbon-14 decay is only usable up to max 70.000 years.
But there exist many other long-lived isotopes to measure.
The uranium-thorium method, the potassium-argon method, and the rubidium-strontium method.
Samples containing radioactive beryllium could be dated as far back as 10–30 million years. A newer method of radioactive tracing involves the use of a new clock, based on the radioactive decay of 235 uranium to 231 protactinium.
We'd really like to know why the known accurate methods didn't work in this case, and why they had to fall back to indirect measurements of the flint stones.
Only for this week! Last week's New Scientist contained an article that had hom. sap. being of eastern european origin rather than african. There was quite a lot of controversy and conjecture though.
(IANAA) The archaeological record is sketchy at best for our prehistory and huge amounts of conjecture is based on very fragmentary evidence. Entire (sub) species are known only from a single bone or a few teeth.
Anyway - cheers to Morocco - cradle of humanity, for now 8)
The clock is "reset" on these types of things so frequently that I can help wondering why we speak so confidently about the origins of our species, and how long we've been here, and ultimately where we came from on this earth.
It's another data point, and must be assessed relative to other data points. Some details of the origin of our species are better known than others, and thus some are more or less likely to be 'reset'. The evidence for African origins, for example, are overwhelming and will not likely be 'reset'. The precise dating of the origin of homo sapiens - if that is even possible - is still in flux. This is the scientific process - science as error correction mechanism.
Before the Dawn by Nicholas Wade is a great book reviewing the recent science on our species from about 100k year ago to about 10k years ago. It provides the overview and context that you dont get from a NYT article such as this.
My impression is that the experts don't speak with a ton of confidence. Popularized versions tend to present the latest "this seems kinda likely, but who knows..." as fact.
1. We find human remains we can date back 100,000 years. Press release that we know humans are at least 100,000 years old.
2. We find human remains we can date back 150,000 years. Press release that we know humans are at least 150,000 years old. We were wrong about #1 (sort of).
3. We find human remains we can date back 200,000 years. Press release that we know humans are at least 200,000 years old. We were wrong about #1 & #2 (sort of).
This particular skull is apparently slightly elongated compared to than of modern humans, so that is spawning some debate, which is good. I don't know if some would consider this a parent species because of this, but probably.
An interesting paragraph I read in one of these articles on this recent discovery is that fossils this old are difficult to find because it requires an dry, arid area to survive. Assuming that humanity started in Africa will probably never be disproven because we would need to find a fossil older than 300,000 years that's not in Africa. I assume we think this based on the only evidence we have: we've only found the oldest fossils in Africa.
> This particular skull is apparently slightly elongated compared to than of modern humans, so that is spawning some debate, which is good. I don't know if some would consider this a parent species because of this, but probably.
Naive question, how do we draw the line between new species and variance of actual homo sapiens? I can imagine some interesting "specimens" of underlying skulls in some people I've encountered that could even fall in another extinct homo species from the images I've seen (sounds funny but it's real question).
I would guess that's up to each researcher. When I was familiarizing myself about some of this on Wikipedia, I noticed that by the time homo erectus came around our predecessors already knew how to control fire and make clothing.
This is more a problem with science reporting than with the science itself.
Saying 'modern humans' or 'homo sapiens' are X years old is a misleading statement. Evolution isn't some binary where all of a sudden you have modern humans. It's genetic change over time.
Better reporting would be to compare this find with relatively modern features in Morocco at 300,00 years ago, to Homo Naledi with archaic features in South Africa at 335,000 to 236,000 years ago. As other users put it, compare this data point to other data points.
This find implies that relatively modern humans had spread to multiple parts of Africa by 300,000 ya, while at the same time evolutionary cousins like H. naledi persisted in other parts.
"And if that is true, Dr. Gunz and his colleagues argue, then our species may have been evolving as a network of groups spread across the continent." This IMO is the best sentence summarizing the impact of this find, and makes the most sense evolutionarily. Instead of having one group evolve all modern traits, and then 70,000 years ago explode across Africa and then the globe, you have several groups with limited interbreeding evolving 'modern' traits. The interbreeding allows the traits to cross into other groups, and modern humans are the result of a particularly successful combination of traits where some traits arose in one group or location and some in others.
So sure, in evolutionary deep time (1-2 million years) East Africa remains the cradle of humanity. But this find updates the story that by 300,000 years ago, the groups that became human had left the cradle. That's a big story, and is a much better summation than the misleading "Humans are X years old, older than Y that we previously thought".
> and ultimately where we came from on this earth.
I will always hope that we find some clue which suggests humans came from somewhere other than Earth. That would probably be the second best thing, after proof of extraterrestrial intelligence, to spur deep-space exploration.
I'd love some good science fiction based on that idea at least. Mars seems like a plausible candidate; We ruined it/were forced to leave, fled to Earth, culled the dinosaurs, and made here home.
I know there are probably some very good evolutionary explanations for human beings, but to a complete layman like me, the difference between human and ape intelligence are way too much to attribute to an accident of natural selection.
Plus, I think an extraterrestrial source for human life just makes me think of all sorts of geeky fantasies.
What about hybridization? There's a hypothesis that once a primate mate with a pig and the resulting hybrid become humanity ancestor. It can explain a leap in evolution and explain things like lack of hair.
Isn't science marvelous? That fact that it adapts as new evidence is revealed is critical. The confidence you mention is not confidence that a final answer has been reached but rather, based on the current evidence, an answer can be formulated that is consistent with that evidence available at that time.
> The clock is "reset" on these types of things so frequently
It really isn't; this doesn't change anything, we previously knew we were at least 200k years old, that fact is still true. We now know we're at least 300k years old, that fact will also always remain true. What's at fault is your understanding of what science is saying rather than what it's actually saying.
> that I can help wondering why we speak so confidently about the origins of our species
Because it's a given that we're always speaking about current best available knowledge. What is proven true remains true, it's just refined over time as new truths are discovered. What we know continually grows, it's not like we're changing what we know to be something else, we're just growing what we know continually.
But seriously, what the heck makes more current information better? We aren't talking about significant technological advancements in the last 30 years in dating. What about releasing the click bait news story when a date is corroborated by a new piece of evidence, instead of every time some new find is dated we change the scientifically accepted just to the new number. gnaritas, its hilarious how you ask a very legitimate question, and then the responses are all "Isn't it great how the scientific method allows us to blatantly...." Instead of a response like "Oh...why the heck did we say we had so much confidence before" Regardless of what commenters say, the truth is that yes, without corroboration or quantifiable changes in technology, there is NO VALIDITY in saying that the newest number is the best number. It's another data point, and more importantly its another data point to prove that its stupid to so quickly decide that once you find something in 1 hole in 1 location, that artifact MUST be the beginning of an era!
It's not about the newest number being the best number, it's simply an older number that changes our idea of the timeline. So yes, it there is validity in it because it's "new" data that differs from our existing data giving us a fuller understanding of the timeline.
And I think you're confusing me with the OP, I didn't ask any question at all, nor do I think the OP's question is legitimate. The OP is assuming incorrectly that current science states definitively when homo sapiens began, but it doesn't, it merely says here's the oldest evidence we currently have so we're at least this old; science never said we're not older. As we cannot time travel, we can never definitively say when homo sapiens began, it will always be an estimate based on the oldest fossils found and as such that estimate can be changed anytime new fossils are found that pre-date the existing oldest fossil.
Then I want my quarter back. The pacing of this game sucks, over a third of the game-clock is mostly grinding, another third is spent on hallucinating nonsense, and the "plot" seems like it is made up as it goes along.
But that's what exciting about science. It doesn't claim to come with ready made answers about our surroundings, humans discover things on their own.
Sometimes humans get things wrong, and there is no shame in being wrong with science, it's part of the process, unlike "other domains" where people can or will never admin they are wrong, while still using the product of science every day, in contradiction to their own "science".
Please let's not have generic science vs. religion threads (a.k.a. flamewars, because that's what they turn into). This comment wasn't so bad, but it predictably led to much worse because it's impossible to say new or substantive things about anything so generic.
I don't know, the inability to admit being wrong is a human trait and can apply to anyone, including scientists and believers.
Why does everyone think that there's only two "origin" stories and they're both mutually exclusive? I believe in evolution, and I'm a monotheist. I don't reach this conclusion very easily. Why not evolution as God's* way of creating things.
*I hesitate to use this word because of the baggage it carries, but somehow Designer or Creator doesn't seem sufficient here...
Why not evolution as "God's" way of creating things? Well, why not anything? You can posit anything you want, can you test it? Is there evidence to support it?
Why monotheist? How do you know for certain there aren't more gods? How did you arrive at that conclusion? Can you test it? Could you admit your belief in monotheism could possibly be mistaken?
We can ask "why not anything?" all day and not get anywhere so it's more worthwhile to focus on the things for which evidence can actually be gathered. Evolution is testable and there exists much evidence of it occurring in the past. The other origin, not so much.
"Why not" is one way to keep an open mind. Why not this world in a multiverse. Why not this world in a simulation. Why not a simulation within a simulation. Why not a programmer who wrote the code for this world - and how is this any stranger than our other what ifs.
We're human, we don't just operate on facts - we rely on educated assumptions that we make, some of which may be strong enough to translate into belief. This may be driven by evidence, or just our humanly intuition and experiences.
But this is also human: The beauty of science is that it adapts as new evidence is revealed - someone here said this earlier. [No final answer] but rather based on the current evidence, an answer can be formulated that is consistent with the evidence available at that time.
It's human because it depends on our perspective; where we are in time, whether we find the truths (evidence) or not, and whether we are capable of perceiving all truths. Science is continually evolving in our minds - or more accurately, in the collective minds over time. Can the great jigsaw puzzle ever be solved? That's not the aim of science, as it is proud to point out, but it argues that whatever picture we come up with, it's justified as long as it's based on the current collection of evidence - this is a philosophy.
And I'm personally not satisfied with this, as a way of life. Why don't I deserve the truth in its entirety, in my lifetime? You would ask, why do I even question whether I deserve or not? I guess it's a human thing. But for me, as a person, I intuit closest to monotheism. Monotheism provides a framework where anything is possible, but bound by the belief in the Great Programmer who can do whatever he wants. It can work for anyone, regardless of their time and place; and for me as a person fortunate to live in an advanced age, I can accept evolution, because I think it's pretty robust and who am I to question how he creates the world. This for me is more liberating than having to accept whatever picture current evidence is showing - actually, I look forward to witness more development. It's also quite a comfortable position to be in; if science does show that we live in a simulation, that's OK, if it shows that we live in a multiverse, that's cool too.
I used to be a monotheist and found the certainty it provided quite reassuring. It took a lot of time and contemplation in order to move beyond that, but now I'm quite comfortable to live with the uncertainty resulting from a non-faith outlook.
There are even some traditions that acknowledge the uncertainty of what we know e.g. [1]
But, after all, who knows, and who can say
Whence it all came, and how creation happened?
the gods themselves are later than creation,
so who knows truly whence it has arisen?
Whence all creation had its origin,
he, whether he fashioned it or whether he did not,
he, who surveys it all from highest heaven,
he knows - or maybe even he does not know.
The thing is it's just not very interesting what you "intuit". You're free to do it, but it's of no consequence. Some things that are interesting are (1) observations of reality that allow us to choose among competing hypotheses for how reality works and what has happened in reality, and (2) such testable hypotheses.
If there is a god, of course there are consequences. (This opens up another mess of a rabbit hole so I'll stop here!)
You're right, I "intuit" it because it's unifying and seems to cover all bases, and therefore quite a comfortable position to be in. I also "intuit" it because of the vast indescribable complexity of this world, and it's not just the equations but the thrill, humility and beauty of it all is too much that I have to accept that it doesn't just happen.
But in my earlier point, I wanted to show that a belief in a 'Great Programmer' is not incompatible with a belief in science. I am free to be interested in those two things you mentioned, but I can also attribute the wonders to a god. In a way this is like enjoying an unfinished picture/ story, but knowing how the thread begins and ends: everything comes from him, and everything returns to him. It's like sitting in the privileged seat to witness a slice of this drama. And for me, the least I can do is to acknowledge the great auteur behind it.
That's great but it doesn't prove anything. You're free to believe anything you like, or anything you intuit, but that has no bearing on whether it's true or not.
So, the reason I find those two origin stories can't coexist? Simply because there is no evidence to suggest one of them is remotely true. It's nothing personal. I too believe many things, but I'm happy to admit I may very well be wrong. Call them operating assumptions.
Yes but see, the same uncertainty also goes to you. Evidence may paint a picture, but evidence is also continuously fluid so there is never a correct picture. A more accurate picture, possibly. But even so, we're not just ruled by rational thinking. Even scientists are driven by a thing called wonder and curiosity - you need those facilities together to make progress. Call intuition as one tool to take advantage of.
But hey I may be wrong too. There's no telling unless He says "Game's up, now who amongst you could see me." I admit that there is that fear in me, but as I explained in another child post, I just can't put down the super complexity and beauty of this world to a chance.
(If my tone seems condescending, I apologise as this is not in my intention at all.)
Of course I can only be as certain as the evidence we have. I also know that our understanding will probably evolve and change and we learn new information.
As for chance? Well, for every Earth (only one we know of) there are (as far as we know) billions of dead planets. After billions and billions of dead planets I'm perfectly will to accept that one with life is just chance.
That's not the only chance though. It's a chance within a chance within so many other chances over many, many years, from the moment the Big Bang happened.
For sure our knowledge will grow, but I am not so sure if this will apply to our understanding. Yet the more we know, the more we seem we don't know!
Hey thanks for letting me indulge in this thread, I was hoping to test my thoughts and learn something new (I did) :)
Unfortunately, you can't test evolution in the same way that you can test for example if an artificial organ will function in an animal. You can only speculate about the past.
The current Pope is cool with evolution. I think this is a common view, especially among religious scientists. Only some people think evolution is incompatible with divine creation.
Not that you're wrong, but this isn't exactly news. St Augustine, back in the late 4th century/early 5th, was "cool" with evolution, if you care to use those words:
"Th[e] tree surely did not spring forth suddenly in [a mature] size and form, but rather went through a process of growth with which we are familiar. …[It] took its shape as it [gradually] developed with all its parts. … One [form of tree] comes from the other [form of tree], therefore, in succession, but both come from earth and not earth from them. Earth, then, is prior and is their source. The same is true of animals." (http://www.historyandapologetics.com/2015/02/st-augustine-on...)
While he didn't think that a new genus could arise in this way, he was pretty clearly on the right track, especially given the rather sketchy knowledge on the subject of biology in his day.
I have so much respect for archeologists. Spending over a decade in one spot, literally on hands and knees, digging and meticulously sifting through anything that is found, is to me the epitome of dedication to a craft.
But another part of me thinks: there must be a better way!
I know that expeditions often hire bands of locals to help them dig and sift. But does anybody know, have there ever been any advances in this field to make the process go faster, or require less human toiling?