Monkey stone tools shed doubts on the human origin of archeological sites | Hacker News Reader

Monkey stone tools shed doubts on the human origin of archeological sites

journals.sagepub.com

174 pointswslh119 comments

I only skimmed the article, but I just wanted to point out that the provided HN title differs significantly from the actual paper title, in a way that is potentially misleading.

The stone tools use in question is not the flintknapping that we usually think of. It is, in essence, just picking up a rock and using it as a hammer to bash things. Nor is this paper purported to reset the timeline on early human anthropology. The archaeological sites in question are a specific set of sites in Brazil where evidence of that kind of tool use had been interpreted by some to be evidence of early human presence in the Americas. As the article itself points out, though, that has been a subject of debate for decades. The earliest citation for the monkey hypothesis for the origin of these sites that I noticed the article mentioning is from 25 years ago.

Cool! I was unaware there were non-human primates that made and used stone tools. Sucks for the archaeologists of course, but I get the impression that theirs is a profession where you must constantly revise in light of new evidence.

Now, if it turns out that ancient DNA is all bunk, I’ll be very sad indeed. Understanding the origins of the human primates is so interesting, but maybe we will never have enough good data to be confident of much. There are limits to what we can figure out, but that’s never stopped anyone from telling a good story!

But looks like this, as of now anyway, only applies to new world species and thus sites in the South American continent and not Africa or Asia.

It's been known for awhile that modern humans aren't the only tool users. Neanderthals and other archaic humans are straightforward examples, but western chimpanzees also do it pretty frequently. Even outside the apes, macaques are known to use stone tools for foraging and sexual gratification.

Lots outside primates, too.

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

Birds, dolphin, octopuses, otters...

Sure and I guess Neanderthal tools would have produced similar tool shapes to those produced by historical humans.

What this paper is saying is that S.Am. primates may be responsible for primitive tools previously associated/attributed with/to humans (due to how they look/characteristics) in some South American sites but this aspect casts some doubt on the origin of those sites and thus affects chronological occupation of the continent by people.

Modern humans (homo sapiens) are ~200,000 years old. Tool use goes back ~2.5 million years.

These days, homo sapiens is more like 300-350 ky old, and (Lomekwian) tool industry is 3.4 My old :

https://tauromachy.wordpress.com/2018/07/05/the-lomekwi-tool...

Which puts into question the naming of homo habilis (="handy man", that 2.5 My old Oldowan tool industry you seem to mention comes from) and australopithecus (responsible for Lomekwian) as "not-homo".

Tool use is of course much older (other primates) and other animals also do it : dolphins, crows...

Can this capuchin-monkey example be called "tool industry" ?

Who wrote that? They seem clear that they have no expertise.

https://tauromachy.wordpress.com/2018/06/06/a-kind-of-introd...

Lou Keep.

Also known for :

https://loukeep.substack.com/p/vagaries

But especially :

https://samzdat.com/

They might not have expertise, but they know how to write. And (from my own, admittedly layman's searches) I haven't seen anything contradicting the main claims.

> They might not have expertise, but they know how to write.

That describes the sophists (by the modern meaning), those who can communicate persuasively but are liars. I'd much rather have the opposite.

No, it doesn't : to be able to lie you need to have expertise. You can bullshit though. Or, and so far this is my impression here, you can also take the expertise of others and present it better (that's what the best science journalists do !)

Question for any archaeologists or zoologists. Do seagulls using the coastal rocks to break open oysters and clams by dropping them from the air qualify as using tools? If not, what is this type of activity considered?

IIRC that should count as using tools, but that's still a step away from making tools.

Are nests tools for child-rearing? Or is that making furniture without the use of tools?

Beavers make dams and build lodges. Bees build hives and have division of labor… at dome point we have to declare a cutoff.

Sure, I just think it's interesting, and that surely you do need to think about why you're interested in whether an animal 'makes' or uses 'tools' to know where that cut-off should be, otherwise it's a bit arbitrary and self-fulfilling ('only humans and some apes use tools' ... 'where tool is defined as a manufactured object held in the hand'!) isn't it?

IIRC, Bees build their hives with their own secretions. I see this as categorically different than animals that make nests out of various items laying around. In the case of a beaver I think it is more advanced than a birds nest because they actually harvest specific trees instead of using what’s on the ground already.

That's a good question (I think, I'm not one of those either) - it's about as close as they could possibly come with the body parts available, so if we're interested in the intelligence and ability to reason about using things to do other things ('tools') then surely it is.

Surely it's possible for an animal even to know its limitations, and desire to do something outside of them. Like I might think 'if only I could fly up and fix my gutter', say.

I wonder if monkey archeology will have artefacts described as being ‘for ritual use’?

Landfills become "ceremonial mounds" filled with trinkets and household necessities for the afterlife.

The site at Onkalo is still a mistery. One might suspect that the barrels are some kind of Sarkophagus. Surely a mighty warrior king was burried here with his troops

I assume landfills have been much rarer in past times.

Ex-archaeologist here. You are correct, less people less trash, but you might be surprised.

Archaeological landfills are called middens[0], and they're more like trash heaps than landfills, but there's a lot of them around the world.

A quick primer from dig it Scotland on middens: https://www.digitscotland.com/a-load-of-old-rubbish-what-mid...

[0] https://en.m.wikipedia.org/wiki/Midden

I’d assumed that a large part of it was that things were broadly biodegradable. Bone and pottery seems to be found, but a lot has rotted away.

Near me there are a lot of middens and it’s just shells now, presumably from nearby Maori pa sites.

I am no expert, but I have always joked that instead of the Stone Age, it probably should be called the Wood Age. There were probably some awesome wooden structures or techniques that have been now lost to the ages because they are no longer around.

Good point, bearing in mind that working wood with only stone and wooden tools is a lot harder than with metals

Working, well, anything we're still going to see traces of would've been even harder harder with only stone and wooden tools than it would be to work wood. It seems pretty reasonable to guess that if we see a culture with stonework and pottery and access to wood, they probably also did stuff with the wood that hasn't survived. (We can then look for evidence, like tools that seems like they they make the most sense to be using for woodwork.)

I'm not sure if it's correct, but I remember a tv show about archeology in East Asia, and they claimed that the problem is that they made too many tools of bamboo (that decompose) instead of tools of stone (that is forever).

Not picking on you, more on this kind if comment.

I think it is easy to be snide about fields like archaeology when you come from a field of absolutisms and proofs, but what else are they supposed to do with gaps in knowledge? We don't have to approach CS work wondering if the 1s and 0s we found were naturally occurring, or put there by some level of intelligent being. Our field in entirely of human construction.

The extension of this attitude leads to situations where Talib is berating a Classics professor for there being 'no data to back up her claim'! As if we can't study anything without data, or we should ignore history until there is something for a mathematician to work with on it.

Perhaps we should poke fun at the physicists who talk about 'dark matter' in the same way.

What a boring world it would be without shifting knowledge of the known and unknown.

On the other hand "I don't know" is a valid, and (should be) an acceptable answer.

'ritual use' is code for, I don't have a clue what practical use this thing could have.

This isn't about known v unknown, it's about being intellectually honest and admitting the unknown.

I can’t know is what’s lacking from the zeitgeist. Too many people say I don’t know which implies they can. No, often it is can’t know.

Really?

What is the meaning of life? Where did the universe come from?

Some of the most interesting questions are unanswerable / don't have a correct answer.

In the field of archaeology there generally isn't the absolute 'can't know' though. Until the Rosetta stone came along we didn't know what various hieroglyphs meant. But the hypothetical existence, however remote of another Rosetta stone means we can know the answer to these various questions.

"I can't know" is good shorthand for "this cannot be known with precision, given available information."

Good scientists discuss and, when possible, quantify uncertainty.

Is it good shorthand? Seems as flawed as hypothecating ritual use.

Again if you don't know something, just say you don't know. If something can't be known, hypothecate, fine, but be honest about your ability to know.

Good scientists should surely be precise and intellectually honest at minimum.

Yes, it's good shorthand.

> But the hypothetical existence, however remote of another Rosetta stone means we can know the answer to these various questions.

Partially flawed logic here aside, a Rosetta stone needs to be qualified in this case. We most likely (almost definitely) cannot know whether these tools at these sites were made and used by hominins or monkeys without time travel, as the sites themselves have been processed and additional discoveries likely eliminated as a result of the destruction of the sites. A Rosetta stone in this setting would be a recorded observation by hominins that lived in the time of themselves making and using these tools at every site that is at question, made in a format we could interpret, because anything else leaves open the possibility that at least one of them, and thus many other sites, were made by monkeys.

Recovering this Rosetta stone, or its equivalent, is so unlikely that can’t is the better answer.

I disagree that it's flawed logic.

It is possible to know, we just don't. You for example are presupposing that no technology will come along that will eg allow us to detect fingerprints, or tooth marks in bones or nuts found nearby. You're also presupposing that no new sites will come to light.

If anyone postulated the existence of the Rosetta stone before it's discovery, do you think anyone would have said it's existence was in any way likely?

It’s flawed logic because you are collapsing the idea that you can imagine it with the idea that it can happen. Whether or not it can happen is unknowable, i.e. can’t be known, which is the point you were refuting.

I gave 2 concrete examples. Are both of those impossible?

> Whether or not it can happen is unknowable, i.e. can’t be known, which is the point you were refuting.

If I play the lottery, it is unknowable whether I will ever win, it can't be known. That doesn't mean I will never win the lottery. The possibility of me winning the lottery is independent of possibility of me knowing whether I'm going to win. Which is kind of the point.

But eventually I might win the lottery, and the unknowable question of whether I will win the lottery will have a concrete answer. So by definition, it was never unknowable to start with!

But you can't know something you've never personally experienced. You're collapsing that which you can experience with that which you can't and assuming that because there are things unknown that are possible to experience they are the same as things that are unknown that you can't experience. That's a very different type of knowing.

It is certainly more accurate to say that one may believe in something to be true, but one can't know.

I was personally amused by the GP’s joke about the absurdity of there being any bright lines between different hominid species.

And I was also amused by your quip about the laziness of the dark matter explanation for gravity we don’t understand.

IMHO there is a place for humor here as long as it’s on topic.

Just my 2c.

I liked the joke, but I had to pick on one of the several similar comments... and picked this one

Honestly, I feel like "ritual use" makes for a good placeholder. Cliché is better than creativity, in this instance.

Everyone knows "ritual objects" means stuff without known/obvious use. We know that people's stuff is often hard to explain, with context. This captures it.

Also, a lot of what people do is ritual. We may not see our culture this way, but it's often a good description.

What's a credit card signature? What's a baseball trophy, fidget spinner or star ears figurine?

> Everyone knows "ritual objects" means stuff without known/obvious use

How to distinguish between "for ritual use (for real)" vs. "for ritual use (nudge, nudge, wink wink)"?

Why not say "we don't know yet", instead? Like a normal person.

Because we don’t know if anything from archeology is “for ritual use (for real).” Sometimes people just do odd stuff because it’s cool. Mount Rushmore should make you wonder about giant ancient statues.

In 10,000 years people might be looking a remnants of Christ the Redeemer statue and think it’s clearly for ritual use. But we know it isn’t for ‘ritual use (for real)’ so someone making such an obvious leap would be wrong, thus making other such seemingly obvious leaps could just as easily be wrong.

I would think that Christ the Redeemer would be a good example of something that is largely for ritual use

What specific rituals would you you say it was built for?

Christian deity worship

I understand your point, but that’s not a specific ritual.

Sacramental wine is created for a specific ritual, houses of warship are made for many rituals but it’s easy to pick one of them as an example. But you can’t point to a specific example here because that’s not what it was built for.

To be clear people have weddings for example at all kinds of interesting buildings, but only some of them where built for that reason. This might seem trivial but it is a meaningful distinction otherwise essentially anything interesting becomes a ritual object.

I do see your point too; it could very much be argued that it’s not for ritual use per se, but it’s debatable, and not a good example of something that’s certainly not for ritual use, which is how the commenter was using it

> we don’t know if anything from archeology is “for ritual use (for real).”

I apologize for being unable resist thinking of a counterexample any time someone makes a generalization. Would household utensils found in a sealed burial chamber be a clear case of ritual use for real, or did dead people in ancient times put them to some practical use we haven't identified?

I do think people getting buried in clothing qualifies as ritualistic when the body was presented for an open casket funeral.

However, people still regularly get buried with their wedding rings or similar such items. Do you consider that behavior ritualistic, or just sentimental?

> Do you consider that behavior ritualistic, or just sentimental?

If you squint a little is a bit of overlap in the definitions of those words. I think that’s where the practice lies.

Sentimental: A: marked or governed by feeling, sensibility, or emotional idealism

B: resulting from feeling rather than reason or thought

Ritual: 1: the established form for a ceremony specifically : the order of words prescribed for a religious ceremony

2A: ritual observance specifically : a system of rites

B: a ceremonial act or action

C: an act or series of acts regularly repeated in a set precise manner

https://www.merriam-webster.com/dictionary

That’s fair.

I can’t help but point out that “if you squint a little” is grounds for a great deal of debate. It’s exactly the kind of thinking that makes some sort of “ritual object (for real)” hard to distinguish even when actually living in the culture in question.

Touché!

Mount Rushmore is a good example.

Ancestral leaders, mythical heroes, apocryphal stories. When we describe the cult of a dead Pharaoh of living roman emperor, we're quite comfortable using terms like "cult," "rite," and such. When describing contemporary culture, we call it a political monument, a cultural heritage symbol or a national monument. To future archeology, it's all the same. Washington can be described in the same terms Nefertiti and the reverse. Visitors to the statue are pilgrims. Events taking place there are "performed rites."

It's not wrong describe constitutional judges as a priests endowed with mysterious abilities to commune with spirits of the past to gain knowledge of constitutional mystery. These rites are not that different from the oracle of Delphi.

Why/how isn't Christ the Redeemer a "ritual object." It's a statue of a god worshipped extensively by the people who live in Rio. It has artistic, religious & cultural meaning. Every day, millions of people cross themselves, say prayers, take mass or perform other christian rites. Why is Christ the Redeemer different to the Sphinx or Jupiter?

You can replace "ritual object" with "cultural object."

If we want to use cultural object then sure but saying ritual object implies something.

Suggesting the Kaaba in Mecca is the same category of thing as a giant ball of yarn roadside attraction misses a great deal of context.

Similarly the Supreme Court isn’t really different than any other aspect of government. They have their rituals, but the court had no problem adapting to COVID restrictions and having everyone work remotely.

I once read a great article on HN which I now can't find, which linked Skinner's superstitious pigeons with the development of human technology.

As told by this article, the Burke and Wills expedition in Australia encountered friendly aboriginals who shared with them a grain called nardoo which they ritually prepared. The preparation was convoluted, with many steps which seemed superfluous. After relations broke down, the party attempted to prepare and consume the nardoo as they had observed but quickly succumbed to illness and death.

It turns out that nardoo is extremely toxic without being processed in a very specific way. To Burke and Wills this process looked like a religious ritual. Perhaps many of the steps in the preparation were pointless, but the superstition of the aboriginals in doing it exactly this way was vital because a small change in the process could lead to illness.

We definitely still see this sort of superstition in Western cooking today, Adam Ragusea does a lot of fun mythbusting in this area.

Similar to theories on why Judaism forbids eating shellfish and pork, potentially pointing to a history of death from spoiled shellfish and pork, thus leading to a religious doctrine to avoid them.

People, including knowledgeable physicists and astronomers talk about about dark matter all the time, and with good reason. Let's make theories but be upfront about their shortcomings, especially if they're funny.

> what else are they supposed to do with gaps in knowledge?

Not saying anything about it, or saying "I don't know what that's about" sound like OK choices to me.

Having been in a position where I would maintain archaic software, I can tell you there certainly are gaps in knowledge in CS as well.

> We don't have to approach CS work wondering if the 1s and 0s we found were naturally occurring, or put there by some level of intelligent being. Our field in entirely of human construction.

Well, in hardware engineering and on the lower levels of software you may well have to keep it in mind:

https://community.hiveeyes.org/t/soft-errors-caused-by-singl...

> but I get the impression that theirs is a profession where you must constantly revise in light of new evidence

We call it “science”.

I think the difference being that in for example maths, once something is proven, that’s it. but very little is so concrete in archaeology, and even when something can be said confidently, new evidence can come to light and change those norms

Mathematics is not a science. Every science has the potential for what you describe, perhaps more or less depending on its sparsity of data. The sparsity of data in archaeology is extremely high.

Of course none of this means there were no humans in South America 30kya. It only means this particular site might not be good evidence for such presence.

If no other sites show unambiguous evidence of human presence, we might need to account for that.

There is a site near Los Angeles, excavated by Richard Leakey, that has been rejected as indicating early human presence because there was too much stone-tool evidence, and because "everybody knows" there were no people there 200kya.

Now that we have the unambiguous Cerutti Mastodon site from 130kya, it might need to be re-evaluated.

Generally the null hypothesis is that people went anywhere they could go whenever they could, no matter how inconvenient that is for anybody's chronology narrative.

The Cerutti mastodon site seems pretty far from unambiguous: https://en.wikipedia.org/wiki/Cerutti_Mastodon_site#Criticis...

Wikipedia is the last place to consult for current scholarship. Pages are typically "curated" by retired professors with an ax to grind, who carefully scrub anything that contradicts their grad-school thesis.

The criticisms that have been thoroughly debunked keep surfacing again. Most egregiously, BS about construction machinery.

The only legitimate criticism I have seen is that they didn't find flakes from stone blade maintenance, or a hearth. Of course, that work could have happened 50 feet away, or 500, and not been found. There is way more than enough evidence without.

> Now that we have the unambiguous Cerutti Mastodon site from 130kya, it might need to be re-evaluated.

I don't think you can describe that as "unambiguous"; there is plenty of criticism.

The other site you're referring to is the Calico site, which was excavated by Louis Leakey, Richard Leaky's father. It wasn't just that there were "too many" of them, it was also that the presence could be explained by natural phenomenon. Does this prove it wasn't human-made? No. But given everything else we know, it's unlikely.

> Generally the null hypothesis is that people went anywhere they could go whenever they could, no matter how inconvenient that is for anybody's chronology narrative.

That's not really how that works. The first evidence of modern humans is in Africa about 300,000 years ago. The first evidence of humans anywhere outside of Africa is about 200,000 years ago, in the middle-east. East-Asia about 80,000 years ago; Australia: 65,000 years ago.

130,000 or 200,000 years ago just doesn't fit in with ... anything.

Perhaps pre-modern humans arrived in the Americas much earlier; but AFAIK there is no evidence of that either, or considered very plausible.

Considering how much shit people have always got over evidence that "doesn't fit in with ... anything", how surprising is it that you mostly only know about evidence that does?

The null hypothesis is always that mammals go where they can. Period. You need an explanation for any circumstance when they evidently couldn't go somewhere. It doesn't matter what fits your preconceptions and biases. Humans are mammals.

People got to Crete 200,000 years ago. By boat. Were they H. erectus? H. n.? H. sap.? Nobody knows. People got to Australia 70kya. By boat. We are pretty sure those were H. sap. Anybody who can get to Australia, sailing out of sight of land, can get to lots of other places just as easily: the Philippines, Japan, the Aleutians, etc. Particularly when sea level is 120m lower.

The null hypothesis (if that's even a good one, which I'm unconvinced about, but whatever considering we see plenty of animals that have evolved in the same area without leaving it) is not some ultimate arbiter of what's true. I don't know why you keep referring to it like your claim must be true because it's your null hypothesis or something.

The null hypothesis is what you legitimately need proof to refute.

That is not to say that the rule is applied correctly everywhere.

> The null hypothesis is always that mammals go where they can. Period.

That's not how null hypotheses work

The null hypothesis is that 2 variables are uncorrelated. You can't just call your hypothesis "the null hypothesis" to try to make it sound more likely.

It is a matter of where the burden of proof legitimately is, and what evidence you need to bring.

If you think humans were blocked from access to North America, you need a mechanism to have blocked them, and evidence for it. We know that the fossil record is absurdly thin, and get our noses rubbed in it each generation, but seem never to learn better.

A human being with the ability to hunt and gather their calories could easily walk across the planet. That endurance is practically our species' special sauce. Without a clear reason why that couldn't happen, we should be open to much more complex narratives of human history than existing dogma asserts.

This is probably true for neanderthals, denisovans, and H. erectus too. They were outside of Africa for much longer than 200kya. These were by all measures humans, albeit very strange ones to our eyes. They almost certainly used language and tools. A basic premise of the posted article is that even monkeys use tools... As for language, it seems more of a religious than scientific question that any primates lack high information content vocal communication.

It is, also, hard to see how tool use in capuchins could be anything other than cultural transmission. I know how biologists are subjected to years of withering abuse for ever mentioning cultural transmission outside Homo, but the excuses have worn thin.

Cultural transmission outside Homo is everyday fact now.

> A human being with the ability to hunt and gather their calories could easily walk across the planet.

What evidence is this based on? This is fantasy, particularly 200kya.

> neanderthals, denisovans, and H. erectus … were by all measures humans

This is untrue. We have no evidence that any of them used language or even symbolic thought.

Burials with grave goods are reliable proof of symbolic thought. Beads are reliable proof.

Denisovans used rotary drills 70,000 years ago.

Nothing about H. sap. was different 200kya except culture. Physical remains are so thin, and so little even looked for, that lack of it anywhere tells you practically nothing.

Ok but this does not match what you said above. There is a long timeline here and interbreeding is a factor. Denisovans are certainly possibly just small H sapiens but H erectus did not exist 200 kya and Neandertals had a substantially different brain case. My guess is if they got language they got it via interbreeding with H sapiens.

The lack of evidence does create a lot of space for suggesting pretty much anything.

"The last known occurrence of Homo erectus is 117,000–108,000 years ago in Ngandong, Java."

Denisovans' rotary drilling predates known H. sap. rotary tech by tens of millennia.

An article talking about this: "Monkeys Trash Theory of People in Americas Tens of Thousands of Years Ago" https://www.haaretz.com/archaeology/2023-01-05/ty-article/mo...

I'm kind of suspicious that neither the abstract nor the article shows a picture of anything resembling a stone tool. Perhaps the field has been defining random rocks with hammer marks as "stone tools" for excitement, and showing a picture would have made people say "well a monkey could have done THAT" all along?

This is exactly what has happened in many cases.

“Shed doubts”???

Since when is that a turn of phrase? You “cast” doubt (like a shadow), and “shed” light.

If you can shed light on something, why can't you shed a couple doubts on it too?

Because that would be ridding yourself of doubt, not gaining new doubts.

If you "shed light" are you not casting light or exposing to light the subject?

So in this context you would gaining new doubt.

I always assumed this came from shod as in a horse shod with shoes.

For some discussion, see https://languagelog.ldc.upenn.edu/nll/?p=3828

We used to think that humans were the only animals to use tools, but this was disproven long ago: otters use rocks to break open shellfish, birds use tools to create their nests, etc.

Then, we thought that humans were the only animals to fashion tools, not merely pick up objects from their environment. This was also disproven. Primates sharpen sticks to hunt, bend twigs to get ants out of trees, etc.

Today, we believe humans' unique relationship to tools is recursive: we're the only animal ever observed to use a tool to make a tool.

It's this capacity for self-referential thought that sets us apart from the rest of the creatures on earth.

There's tremendous intelligence in the animal kingdom: Octopuses and crows can solve complex problems, dogs can manipulate humans, dolphins can transmit visual imagines to one another through sound.

But self-referential thought is why a human built this website and other animals could not.

There’s always something that sets us apart, isn’t there? Something that makes “us” better than “them”. Or so we tell ourselves as we continue to rape the planet and kill our cohabitants. The mind can be quite resourceful when faced with cognitive dissonance.

I attended a talk in college by a guy who had measured a bunch of cultural attitudes toward animals, nature, the environment, etc. from different cultures all around the world, then ranked them from most empathetic to least empathetic.

He found the #1 contributing factor to be whether or not that human population coexists with monkeys.

Monkeys are the link that connect us to the animal world. Looking at the face of a creature that is similar to your own is tremendously powerful.

I think it's natural to wonder about our place in the world, but you're right: we shouldn't think of ourselves as distinct from it.

"Monkey stone tools shed..."

For a second I read it that way and thought "Bloody hell they've got toolsheds now?"

Are there photos?

I initially misread this as being about a monkey with a toolsheld.

If those were monkey tools, why monkeys didn't evolve since then?

They did.

A common misunderstanding of evolution is that it means a population of X becomes a population of Y. In actuality, it means a population of X becomes a population of X AND Y. If X and Y aren't competing for the same resources (speciation commonly happens to take advantage of a different set of resources), then there is no reason they can't coexist indefinitely.

I blame Pokémon for this erroneous view of evolution. Your Charmander has evolved in to a Charizard!

This made me laugh but also made me think about what does and does not evolve. Sharks and the coelacanth fish are often mentioned as modern animals that “have never needed to evolve”. Guess it’s just based by comparing current physiology/structure to what fossil records can be found. Of course “everything evolves” but that depends on a frame or reference in time

> everything evolves

Not necessarily, some things go extinct.

Or, evolves in to what?

Perhaps we can be certain that every changes. Maybe that's cyclical too.

Sharks and coelacanths have evolved exactly as much as humans.

The difference is that they have kept a more-or-less constant body plan, and evolved details less easy to see.

The monkeys have also evolved exactly as much as we have. Again, it is less easy to see the evolved differences from their ancestors, because their bodies are so superbly adapted to their way of life and so have not changed much.

Surely this is wrong if we're talking about genetic drift which has no reason to be linear with time ?

It's also wrong if you're considering the number of generations available for evolutionary selection pressure. But it's less wrong than what it's rebutting, so I'm happy to say it's rhetorically correct. (It'd need to be a bit more precise to be pedagogically correct, à la lies to children, in my book, because it is still misleading.)

Acknowledging, generation time is a legitimate counter.

This is not true. They have not evolved/derived as much for a number of reasons including differing mutation rates, minimal environment change, selection against adaptation, etc.

It is not visible vs invisible changes that progress at some fixed proportion to reproductive rate; that is a gross oversimplification and conceptually inaccurate.

See e.g. Sewell Wright’s fitness landscapes.

Isn't 'need' the wrong word.

They just haven't happen to produce an advantageous mutation ..... That changes their form enough to cross some arbitrary line where we would define 'evolving'

In case you are seeking an answer, consider that birds instinctively build nests but (most) don't put roofs on them although the process would be a logical continuation of what they can already do.

Because what they have is good enough.

Without selective pressure, evolution just dithers around what already works.

There will be reasons they got to where they are, that they remain just indicates those reasons have not gone away.

I'm not so certain that it's logical, considering how birds would tend to be away from the nest during the warm days in search for food, and back incubating the eggs during the cold of night, while a roof over a freestanding nest would require much more investment of materials and effort (especially for a species without hands !) ?

And of course a lot of species of bird achieves this by nesting in (vertical) holes.

Also the nest needs to be hidden and a roof would be much harder to spot. So building a roof, that does not draw attention and can resist strong winds would indeed be much harder. Also usually there is some sort of roof and protection by overlapping branches and their leaves.

Imagine a penguin looking at a albatross and saying:

"If they are eating fish like us since many million of years, why didn't albatross evolve since then?"

I choose albatross because the birds more related to penguins are albatross or something similar https://en.wikipedia.org/wiki/Procellariiformes

I'm not sure what happened when the ancestors of penguins split from the ancestors of albatross, but let me guess: <guess> They lived in different areas. In one areas there were less fishes per area and they had to continue flying to catch enough fishes. In the other are there were more fishes, but they lived in deeper water, so they have to enhance the diving abilities. <)guess>

Perhaps my guess is bad, or very bad, but I hope you can imagine that the same birds living in different areas may have different food source and different fishing strategies, so in each are the birds that were better for that strategy outnumbered the other birds, and after 60-80 millions year they look very different.

Both evolved. albatross look quite birdy like the ancient ancestor, penguins look weird.

Great explanation, one thing missing is extinction events. Small extinction events in a matter of decades (for birds) drastically influence characteristics that are favored or disfavored - like a drought, or too much rain, or invasion by another species or whatever. Apparently[1] the characteristics that help animals eat in threatening times are the ones that drive evolution.

[1] The Beak of Finch book

> I'm not sure what happened when the ancestors of penguins split from the ancestors of albatross

My guess, similar to yours will added a reason :)

Flying consumes a lot of energy. My guess is some albatrosses found a place where there was a lot of food, very safe and then hardly ever needed to fly. Thus the move to penguins.

Without an extinction event, they can stick around for as long as possible. Both evolved. It's like how we had neanderthals, denisovans and homo sapiens and homo heidelbergensis all on this planet at one point.

Becoming more intelligent isn't necessarily the final outcome of evolution.

Upvoting because the question, while looking dumb, is very legitimate, if only for some of the answers it calls for.

And that’s what makes good questions.

Two easy options: lack of a sufficiently complex language to transfer ideas and social organization. If a species doesn't get over those hurdles, evolution happily takes another path.

And about intelligence: we may not be (or have been) that much more intelligent than certain other apes, but we can learn from other humans from thousands of years ago thousands of miles away. That makes a difference.

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