New human-like species discovered | Hacker News Reader

New human-like species discovered

bbc.co.uk

635 pointsm1k3r420211 comments

Awesome to see the Rising Star Expedition on HN! I was working in Johannesburg while the expedition was active and my partner managed, through a serious of very fortunate events to become a caver on the expedition. Here she is carrying up some of the first bones they extracted - https://i.imgur.com/IfT4PQz.jpg.

For those of you interested, the expedition was sponsored by National Geographic, and there was/is a fairly extensive blog (http://voices.nationalgeographic.com/blog/rising-star-expedi...) covering most of the details. When they first started pulling up the fossils, the excitement was palpable - http://voices.nationalgeographic.com/2013/11/11/video-first-....

The expedition occurred nearly two years ago, and there were so many bones still left in the catchment that they left many behind.

Incidentally, though the article says it was scientists who discovered the fossils - they were actually discovered by amateur cavers. The Cradle of Humankind (so named because there are so many similar catchments in the surrounding area) has a massive system of caves and some of the most hardcore amateur cavers in the world.

> Incidentally, though the article says it was scientists who discovered the fossils - they were actually discovered by amateur cavers.

Indeed, some more details here: http://www.news24.com/SouthAfrica/News/Accountant-found-Homo...

Is this a correct mirror for the video? The player on natgeo is not even sort of working here.

https://www.youtube.com/watch?v=1_r3UnkjcL0

That's the one!

I live 15 minutes away from The Cradle/Maropeng. definitely going to the exhibition one of these days, very interesting discovery indeed!

I had to re-read the comment a few times before realising that you wrote "caver" and not "cadaver".

That's incredible!

The Guardian's coverage of this contains a fair amount of scepticism:

Christoph Zollikofer, an anthropologist at the University of Zurich, said that many of the bone characteristics used to claim the creature as a new species are seen in more primitive animals, and by definition cannot be used to define a new species.

“The few ‘unique’ features that potentially define the new species need further scrutiny, as they may represent individual variation, or variation at the population level,” he said.

Tim White, a paleoanthropologist at the University of California, Berkeley, goes further. “From what is presented here, they belong to a primitive Homo erectus, a species named in the 1800s.”

“Intentional disposal of rotting corpses by fellow pinheads makes a nice headline, but seems like a stretch to me,” said Jungers. Zollikofer agrees. “The ‘new species’ and ‘dump-the-dead’ claims are clearly for the media. None of them is substantiated by the data presented in the publications,” he said. Hawks is open to other explanations, but said that disposal made sense. “The evidence really tends to exclude the idea that they entered the chamber one at a time, alive, over some time, because we have infants, small children, and very old adults who would almost certainly not have managed to get into this chamber without being deposited there.”

http://www.theguardian.com/science/2015/sep/10/new-species-o...

Do we still depend on bone structure to define species? DNA analysis is indisputable. Its all speculation until that is done.

Is there any chance of doing DNA analysis on 3 million year old (presumably fossilised) bones? If in fact that is how old they are.

No. There is basically 0 chance without some sort of extraordinary preservative (like ethanol).

A species cannot be clearly defined until you try to mate it with something else and it fails to produce a viable offspring, as far as I'm aware. No DNA analysis is indisputable with what we currently know.

So each infertile individual belongs into their own species?

Each one of an infertile individual's parents belongs to its own species.

Until they get another child that does turn out to be fertile.

You can't use such a literal-minded interpretation in the real world. The real world is complex and fuzzy.

For instance, in species with sexual differentiation, two males or two females cannot mate, but are considered the same species.

For a more precise definition, you would have to, say, look at the probability that a pair of organisms of the appropriate sex from two different populations would be able to mate, and produce viable offspring (that is, offspring that could themselves mate and produce more offspring).

Asking about a single organism that happens to be infertile, or a single pair that happens not to be able to mate or produce viable offspring, is not particularly interesting, but at a population level you could use a statistical test to get a probability distribution, rather than a yes or no answer.

See https://en.wikipedia.org/wiki/Species#Difficulty_defining_or... for more information.

Note also that it can be the case that two different species can mate, and produce offspring, but the offspring itself is not viable (cannot mate and produce offspring). This happens in the case of mating two closely related species, such as when mating a horse and donkey to get a mule (https://en.wikipedia.org/wiki/Mule), or a lion and a tiger to get a liger (https://en.wikipedia.org/wiki/Liger).

One method of speciation is reproductive isolation. One model for this is the Bateson–Dobzhansky–Muller model, where if a species is, say, separated by distance, and then subgroup A has a change at one loci, and subgroup B has a change at another loci, and due to these mutations, individuals from subgroup A can no longer reproduce with individuals fom subgroup B - then it can be said that speciation from reproductive isolation has occurred according to this model.

Not always, but some infertile individuals belong to their own new species, yes. It happens all the time with plant hybrids.

Plants can clone itselves so to be infertile is not the same as to be extinct for them. Infertile also means normally something like "99,9999% unable to produce seeds" but with enough time and a high number of tries, planets will align in the polinisation of two "unfertile" stems of the same plant. At the end seeds will be produced and the new species will exit the 'trap' perfectly (or all DNA of the father will be discarded reverting to the original mother species). Is just a question of time.

yeah, and things can get complicated: https://en.wikipedia.org/wiki/Ring_species

My impression of defining species wasn't necessarily can they mate, but rather will they mate. Geography and sexual discrimination play as much of a part in separating species as does fertilization.

I'm not a biologist, but my understanding is that animals that can interbreed but usually wouldn't are (if at all) divided into subspecies within the same species.

See https://en.wikipedia.org/wiki/Subspecies

"A taxonomist decides whether to recognize a subspecies or not. A common way to decide is that organisms belonging to different subspecies of the same species are capable of interbreeding and producing fertile offspring, but they do not interbreed in nature due to geographic isolation or other factors."

So me and Taylor Swift are two seperate species?

In all seriousness, species definition is a case of trying to define a black/white classification in a gradient. It might sort of work in higher animals, such as mammals. But it certainly breaks down in bacteria, which is clearly seen since it's possible to compare genomes on population level.

So dogs and wolves are the same species? I know that different species usually cannot interbreed, but I don't think that's the sole criterion.

Interestingly, yes.

"The domestic dog lost its recognition as a separate species in 1993, and is now considered a subspecies of gray wolf."

http://karmatics.com/docs/evolution-species-confusion.html

"Species" is very clearly defined by "speciation": the point where something becomes too different to interbreed. Usually when two things can interbreed, but have many differences, they are referred to as separate subspecies of the same species.

That's a junior high level of explanation tho. 'Species' is ultimately an attempt to impose a quantization of nature, and nature can't always be quantized in a way we'd like.

Exactly. Species is more of a descriptive term than it is prescriptive.

That's an old and very problematic definition of species. In fact, I believe biologists tend to focus on populations rather than species these days, since those at least can be clearly defined.

My understanding is that that particular definition is outdated.

Actually, "species" has multiple competing definitions in the scientific literature. For details see: https://en.wikipedia.org/wiki/Species_problem

The biological species concept is probably one of the most popular and very similar to what you are suggesting. In this concept, a species is an interbreeding population that is reproductively isolated from other populations (either due to genetics or geography).

There are multiple definitions of species, and we choose whichever abstraction is most useful for a given approach.

The concept of species exists purely as a human, scientific abstraction: evolution/biology doesn't give us absolute categories that you can unambiguously put any organism into.

Isn't the ability to produce fertile offspring a de facto proof that two organisms are of the same species?

Depends on the context, but generally nope. Consider the example of "ring species"--A can breed with B, B with C, .., Y with Z, and Z with A. However, A can't interbreed with M. What's the species?

That's a somewhat rare version of a general pattern where that abstraction is leaky. Much more common is a temporal version of that. A might beget A1 and B, with A1 begetting A2 and B begetting C, continuing all the way down. And though A can interbreed with A1 and B, and B with C, etc, Z can't interbreed with A25. That's speciation, which happens all the time. The only thing that makes it a clear species is defining the concept species while abandoning time invariance.

DNA's half-life is 521 years.

http://www.nature.com/news/dna-has-a-521-year-half-life-1.11...

521 not 512, according to the article you mention.

Typing too fast, thanks! The difference probably won't help bridge the millions of years gap though. :-)

Yet we have Neanderthal dna? Oh, right, that's only 40,000 years. Not 1-3 million.

Yes. The Neanderthal species supposedly died out about 40k years ago. [1] In this article they talk about a species that may be millions of years older.

[1] https://en.m.wikipedia.org/wiki/Neanderthal

Yea, I wonder how that's reconciled. The Neanderthal DNA comes from a 38k year-old specimen:

> The researchers recovered ancient DNA of Neanderthals by extracting the DNA from the femur bones of three 38,000-year-old female Neanderthal specimens from Vindija Cave, Croatia, and other bones found in Spain, Russia, and Germany.[8] Only about half a gram of the bone samples (or 21 samples each 50–100 mg[1]) was required for the sequencing, but the project faced many difficulties, including the contamination of the samples by the bacteria that had colonized the Neanderthal's body and humans who handled the bones at the excavation site and at the laboratory.

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

2^(38000/521)=10^22, so there must be other effects. That Nature article says

> The team predicts that even in a bone at an ideal preservation temperature of −5 ºC, effectively every bond would be destroyed after a maximum of 6.8 million years. The DNA would cease to be readable much earlier — perhaps after roughly 1.5 million years, when the remaining strands would be too short to give meaningful information.

which I don't know how to square with the 521 year figure. I think maybe 521 years is at the high temp?

Either that, or it was preserved in amber ;D

Isn't half-life dependent on temperature? Perhaps 521 is at higher temps. Also, half-life does not imply full destruction. By definition, it's destruction of half of the molecules. With enough copies, and a low temperature, it could last much longer than 521 years.

I believe it's the half-life for each bond. But 10^22 is plenty high enough that essentially all bond are broken, and certainly not enough left to reconstruct the genome. (You need unbroken sections of certain minimal lengths to statistically reconstruct what was there before.)

I think you're right that it's a temperature thing.

> 521 not 512

Rounding to the nearest whole number.

I'm guessing that shotgun sequencing techniques are used -- that is, you don't need full length segments in order to reconstruct significantly long lengths of DNA. Again a guess.

No, they're not used, because they didn't find DNA -- they found rocks. We're dealing with fossils here, not organic matter. Tissue does not last for millions of years.

Wasn't a scientist able to extract DNA fragments from dinosaur bones by leaving them in an acidic solution?

Bakker notes that lots of what people call dinosaur fossils are in actuality just bone. Fossilization is rarely a complete or perfect process. So this may in fact be bone.

As someone who spent a fair amount of time in academia, this is pretty common. As much as we all like to pat each other on the back, there are always contrarians who want to tamp down or be skeptical of another scientists conclusions.

Even after a few years, I learned there is always in-fighting when a major discovery like this is made. Regardless of where these bones should be classified, it's an incredible find no matter what - which is sometimes lost in the ensuing fray of dissenting opinions.

But isn't a healthy dose of scepticism simply good Science? Peer reviewed results are hard to be sceptical about. My favorite thing about science is that you often have strongly opposing sides both with super intelligent scientists. When everything has been fleshed out, the best and brightest tends to come to the top (not always, but as a generalism it is true).

Virtually everyone was sceptical of the guy claiming to have developed a form of propulsion powered more or less only by light, but then NASA tested the "EmDrive" and sure enough, it seems like the fundamental idea works. (http://www.nasaspaceflight.com/2015/04/evaluating-nasas-futu...)

The supposed thrust of the EmDrive is very small. But the device has a lot of wires with current that can be equivalent to an electromagnet, and very hot parts that can create air currents, and ...

If you have not done few physics labs, it's easy to underestimate the measurement problems and the level of noise in experiments.

Most of the Physics community thinks that this is an experimental error. One symptom is that at lunch in a Physics department nobody talks about this. If this were real it would be a groundbreaking result because it breaks some of the most fundamental Physics laws.

I don't think the scientists at NASA are bogus. They managed to calculate when a probe would reach pluto that was only off by a few seconds. There is still a lot of research that needs to be done on that, but there are those that say it isn't breaking the laws of physics.

We shall see I guess, but it has been replicated in 3 places now taht I'm aware of, two of which are serious science outfits.

The NASA is very big, they went to the Moon but they also published the infamous arsenic life paper ( https://en.wikipedia.org/wiki/GFAJ-1#Biochemistry ).

In a "massless" thruster, the theoretical maximum Thrust/Power ratio is 1/c = 0.0033 mN/KW if you don't want to break the conservation of momentum, special relativity or quantum mechanics. You could get this value with an ideal perfectly efficient laser beam. The latest NASA version proclaims (50 uN / 50 W) = 1 mN/KW that is 300x the theoretical maximum, so if it's not an experimental error, it must be breaking some of the currently supposed physic laws.

> Peer reviewed results are hard to be sceptical about.

With rampant forging of data and results, you better be skeptical of peer-reviewed results too. Reproducibility is an important, oft-overlooked, and under-appreciated part of science.

And when I say peer review, perhaps I meant to say peer reproduced (which wasn't super obvious in the initial comment).

Good point; after all, how can a review be serious if the reviewer(s) don't even try to reproduce the results?

A peer review can identify a very large class of problems with research without actually replicating the experiment.

For example, problems with methodology and sampling, overlooked prior research, bad analysis of results, straight-up non-sequiturs and conclusions drawn from insufficient data.

All of these mean peer review is valuable without reproducing results.

For an extreme example: if somebody publishes a "Cheese found on moon" paper, do you expect the reviewer to mount an expedition to the moon to check?

Those are all excellent points, but even if you don't find any significant problems with the methodology or the math, or any of the other factors, that still doesn't make a complete review--not without replication.

For the 'Cheese found on moon' paper, I would expect the reviewer to clearly state that the results could not be replicated before mentioning anything else. Let readers draw informed conclusions based on a complete picture of the result, including whether or not it was a one-off.

I was kind of surprised that they haven't aged the finding yet. The 3 million years number is being thrown around with zero evidence.

You need organic material to date which in many cases might not exist with the find.

Other than that you can perform rough estimates based on the soil it was found in, but those in many cases might be off by quite a bit.

Something I've never understood (since highschool some 30 years ago) is; when getting partial skeletons perhaps from only a single individual, how can they claim new species? I mean what's diff with that and some hypothetical future anthropoligist looking at siberian with roundish skull thicker brow ridges and that of six foot tall masai with long face and then a sub 5 foot native peruvian and declaring them all different species?

What's stopping a future anthropologist from declaring siberians and pygmies to be different species? It's not done now for political reasons, but the future has no reason to be concerned with the past's special sensitivities.

Consider that "spanish" and "italian" are officially separate languages, while the US and Scotland both officially speak "english". The terminology won't help you predict which pair has an easier time communicating. It's political.

> What's stopping a future anthropologist from declaring siberians and pygmies to be different species?

The fact that they are capable of producing fertile offspring ?

I think the point was: how can you know that when you only have a few kg of bone fragments?

I am more concerned with the scientific racism (https://en.wikipedia.org/wiki/Scientific_racism#United_State...) emanating from that post.

Taking that as the metric how have the writers of the paper in the OP proved that the species that produced these bone fragments was not able to produce [fertile] offspring with any other species (of which they have a few bone fragments), or even with modern humans.

Even with a full genome, or a full skeleton is it even possible? Surely the only way we currently have to determine mating compatibility is to have live subjects to mate/extract gametes from and means to incubate the zygote [and care for it to adulthood].

But then you have ring species such as some seaguls. The gulls in Northern Europe can interbreed with the ones in Canada, which can interbreed with the ones in Alaska, which can interbreed with the ones in Siberia, which cannot interbreed with the ones is northern Europe. So is there one species or two, and if two where do you draw the line?

I would surmise the answer is N-1 where N is the number of separate gull groups. A species would then consist of two gull groups who can mate and this answer assumes there are no mini circles or triangles in the ring.

No idea the academic answer though.

By that definition a particular individual could simultaneously be a member of two species.

Fascinating !

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

> Consider that "spanish" and "italian" are officially separate languages, while the US and Scotland both officially speak "english". The terminology won't help you predict which pair has an easier time communicating.

I'm not certain, but that doesn't sound right to me.

I'm pretty sure Americans and Scots have a far easier time communicating than someone who only speaks Italian and someone who only speaks Spanish.

(Assuming Scottish accents that are reasonably mainstream, not an extreme outlier.)

If I'm wrong, I'd like to be enlightened.

I'm Scottish by birth, but was raised in the US. I don't have a problem with any of the Scottish accents, but American friends consistently have trouble understanding Glasgow patter and certain highland accents. Heck, I add a roommate in college who needed captions for Trainspotting!

That said, it tends to be as much a vocabulary problem as the accent itself. Lot's of colloquialisms to learn.

Correct. Italian and Spanish can understand each other, but with a lot of effort and keeping communication at a very basic level. This thing that we can speak to each other easily is a myth. That said, we can learn each other languages in a matter of weeks.

> we can learn each other languages in a matter of weeks

Not so fast. Even if you limit yourself to a vocabulary made of the most common 10000 words, you still need a lot more practice to differentiate between nouns that have a gender in Italian and another in Spanish, irregular verbs, idioms, etc.

Understanding a language is one thing. Speaking and writing it is a whole new level.

Gendering nouns that aren't actually gendered is one of the stupidest concepts humanity has inflicted on itself.

It's not. Even Old English had grammatical gender, you just lost it with time, along with proper vowel pronunciation ;-)

> Gendering nouns that aren't actually gendered is one of the stupidest concepts humanity has inflicted on itself.

The objects referred to by nouns aren't inherently gendered, gender is a feature of grammar (sex is a feature of some classes of objects, and fairly recently the grammatical term was adopted as a euphemism for sex by people afraid of the word "sex", and even more recently, inspired by that use, as a name of a social construct associated with, but distinct from, biological sex.)

But grammatical genders, while in some languages they have some correlation to sex distinctions, have no necessary relation to them, as gender distinctions may be on other axes entirely.

So the whole statement seems based on not understanding what "gender" is at all.

> So the whole statement seems based on not understanding what "gender" is at all.

Your parent was just saying gender is unnecessary, and you did not answer anything to disprove that, or to prove that they were once needed.

For instance (speaking of Latin), why is Lapis (stone) masculine but Saxum (stone) neuter?

The Romans could have chosen to place all new words on the 2nd declension neuter (the simplest) but instead it (Classical Latin) created 3 more 3rd declension variants on top of the existing ones! And it was more productive, in this 3rd declension, in assigning masculine and feminine rather than neutral, which the 3rd declension also supported!

So what is the reason for that?

I suspect that sometimes we deliberately complicate our languages to make it harder for the less educated classes to speak them properly, thus creating a larger barrier between us and them.

I think it's a mistake to think of natural languages as being rationality, deliberately constructed. They evolve organically, most often without -- and often in direct resistance too -- conscious design efforts. Elements of language are sometimes imposed by deliberate, premeditated campaigns, but these tend to be the exception rather than the rule.

Languages aren't generally products of design.

A few great comments from /r/linguistics on Reddit really enlightened me on this topic.

Gender isn't senseless, it's a checksum strategy for information. It's not even about sex, lots of grammars have genders that have nothing to do with male/female. The point of gender is agreement: if you're talking about something female, all verbs, adjectives, and adverbs in the sentence have to agree, or the listener gets a syntax error. The syntax error helps the listener figure out that they missed something, or that the transmission was garbled. https://www.reddit.com/r/linguistics/comments/3i1695/eli5_wh...

If you get rid of gender, as English mostly has, you end up forced to adopt different constraints that seem equally arbitrary and wasteful, like strict word order and lots of prepositions. https://www.reddit.com/r/linguistics/comments/3i1695/eli5_wh...

Very excellent comment demonstrating the point about English and word order - in Russian, you can say three words that mean "the dog saw the rabbit" in every possible order, and it's still a valid sentence that means the same thing, because Russian doesn't depend on word order. If it was English, "the dog saw the rabbit", "saw the rabbit the dog", "saw the dog the rabbit", "the rabbit the dog saw", and "the dog the rabbit saw" would all mean exactly the same thing, unambiguously, because the gender of "dog" would have to match the gender of "saw". https://www.reddit.com/r/linguistics/comments/1kdxsc/are_the...

I'm sorry, but that still does not explain why the Romans created more gendered 3rd declension variants when using the neuters from the 2nd and 3rd declensions would have made more sense (since the things they were naming were sexless, like rivers and trees and other geographical things) while they would nevertheless have retained the "checksum" and "free word ordering" benefits from a language that declines its nouns.

For example, Finnish is utterly genderless, but it has more declension cases for nouns than Latin had. And so, Finnish affords itself the ability to have free word order and checksum benefits while doing entirely away with the concept of gender.

So I reject your explanation on the basis that it is clear to me that the declension of nouns into cases is what is responsible for the checksum and word order benefits, and not whether a language has grammatical gender.

The free word order seems to come predominately from declension rather than gender, but I don't see how declension provides much in the way of a checksum.

> For example, Finnish is utterly genderless, but it has more declension cases for nouns than Latin had.

That's consistent with simply making a tradeoff. So a Roman could say:

I don't understand why the Finns created more declension cases when they could have just used gender.

As the saying goes, a language is a dialect with an army and a navy.

Spanish and Italian are MUCH more different than American English and Scottish(?) English.

He was probably thinking of Scots: A 2010 Scottish Government study of "public attitudes towards the Scots language" found that 64% of respondents (around 1,000 individuals being a representative sample of Scotland's adult population) "don't really think of Scots as a language" (Wikipedia)

It's a political thing. Species definition is messy, to the point of absurdity.

Indeed, the differences between long-separated human populations are such that even non-racist scientists acknowledge subspecies..

http://dienekes.blogspot.sk/2009/09/is-homo-sapiens-polytypi...

Thanks for posting this. It has always baffled me that we are led to believe that all of humanity springs from one common root. Absolutely ridiculous and goes against common sense -what other species (of anything) has just one single representative??? Who's been selling this and why???

Nobody is saying there was a single pair of people at some point. But something like a population bottleneck resulting from the Toba eruption would mean all future people were descended from a small group of survivors.

And those types of events happen a lot.

Small group?

It went down to estimated 1500 worldwide. That is plenty.

Note that last common ancestor of the most differing human ethnics is something like 180-200k years ago.

Furthermore, with the advent of denser living and agriculture, evolution sped up quite a lot.

> Who's been selling this and why???

The New York Intellectuals, who were connected to the Frankfurt School, who got the baton from Psychoanalysis.

Read The Culture Of Critique by Kevin Macdonald and you will have precisely your answer.

Ideas like Mitochondrial Eve are really popular, and also really popularly misinterpreted.

I think the problem is the "species" construction itself. Remember, it's completely made up by people and has no obligation to reflect the sometimes messy reality on the ground.

I'm more interested in what we can learn about these people (using the term for convenience) than what they are called. When did they live? How much genetic distance is there between us and them? Do modern humans carry some of their genes? Could they speak?

I do seem to remember being taught in school that the definition of species is "organisms that can reproduce and generate fertile offspring".

Apparently, though, it's not that simple: https://en.wikipedia.org/wiki/Species_problem

That's a problematic criterion when trying to classify long extinct species. We can hypothesize, and perhaps there is a point where we can confidently say "These two definitely couldn't mate" (e.g. Australopithecus afarensis and Homo neanderthalensis), but there's always going to be a large gray area. In fact, here's an interesting quote from the OP article:

> A small group of Homo sapiens left Africa 60,000 years ago and settled the rest of the world, replacing the other human species they encountered (with a small amount of interbreeding).

So actually, it seems we are confident that Homo sapiens was capable of reproduction with some of the other "species" we've identified.

Yeah, not that simple at all. To me though, the problem isn't the difficulty of defining the species. The problem is peoples' need to classify things (a problem that goes far beyond scientific classifications). But I recognize that I'm in the minority in that view.

> I do seem to remember being taught in school that the definition of species is "organisms that can reproduce and generate fertile offspring".

Which is problematic for extinct animals. We have no way of knowing if modern humans would be able to produce offspring with Neanderthals, for example.

Actually, I think we do, DNA, and the answer is yes.

The current body of evidence suggests that we could and did, since Neanderthal DNA is present in some modern humans [1].

[1] http://www.bbc.com/news/science-environment-33226416

That suggests we did. It doesn't necessarily suggest we still could. Nicely illustrates why speciation is more complex than "can't interbreed" though.

I call them a Neanderthal "race' not species. Then it might be unclear how different they appear from modern man.

No, we know humans have produced viable offspring with neanderthals in very recent evolutionary past (30,000 years).

While the human species has changed during that time, no doubt we are still interfertile with neanderthals.

If you do a genetic test with 23andMe, they will tell you exactly what percentage of Neanderthal DNA you have.

It's easy to see why it's a problem when we look into the past. Presumably, every creature should be considered to the be the same species as its parents. But go far enough back and your N-great grandparents are undeniably a different species.

If we had a record of every organism that had ever lived, trying to classify them into "species" would be a ridiculous task -- regardless of how punctuated-equilibriumy things are. Since the fossil record is fairly spotty, it's only a slightly ridiculous task.

Species is really a misapplied concept when you look at one current lifeform's ancestry. Everything is a "ring species" with some sufficiently old ancestor.

If species were based on bone structure, how many species of dogs would there be?

I still think it's super weird that they don't count as different species.

There's the suggestion that breeding + fertile offspring is the main concern, but couldn't early humans and neanderthals reproduce, for example? But we definitely consider them separate species.

Dividing lines are hard here I guess.

> couldn't early humans and neanderthals reproduce, for example?

Common misconception, but no, they couldn't.

I have the impression that current research by Svante Pääbo shows they likely did.

Huh, so it is. I took a few courses on prehistoric humanity and the evolution of mankind in college, but I guess I'm out of date.

(Thanks for not being the sibling poster in your response, BTW. "You are wrong." Hurf.)

You are wrong.

http://news.discovery.com/human/evolution/how-neanderthal-dn...

Every couple of rounds of PHD dissertations that notion changes.

The biggest support is a skeleton of a child which is believed to be a hybrid of Neanderthals and Homo Sapience but the morphological bone evidence isn't that conclusive.

http://news.discovery.com/human/evolution/neanderthal-skelet...

What i really don't like about that article is about how they phrased it the mDNA wasn't "Neanderthal", it just had markers which are rare in modern humans, some of those marker also appear mapped mDNA of "Neanderthals".

mDNA aside general genetic markers is a much weaker theory mostly because we cannot estimate well enough how much of the DNA in question actually came through inter-breeding and how much of it might actually survived from a previous common ancestor, or how many of them are just random mutations that survived through natural selection or cultural selective breeding. Because there have been claims before about that like that the gene for readheads came from Neanderthals but then was discovered that that specific mutation is just naturally occurring for humans and the redhead gene of modern humans isn't the same for Neanderthals or other primates.

The 1-4% neanderthal DNA is also a bit well iffy, comparing genomes is very tricky and those comparisons often strip away all the large differences e.g. like humans and chimpanzees only share 99% of the genes when you strip about 2/3rd of the genome.

So while there might have been interbreeding there's very little of actual evidence to point to the extent and the cause of it, could've been social interbreeding, could've been pillage and rape, could've been small isolated cases, could've been widespread, but PC gen-Y notions aside the science isn't really clear on on side or the other and it's hard to know if it ever will be able to be.

Geographic and chronological/geological isolation probably play a role. Populations separated by kiloyears and megameters are probably more likely to be considered species.

Here is a short video of caver Rick Hunter squeezing through one of the tunnels to the Dinaledi Chamber. Not for the claustrophobic. https://www.youtube.com/watch?v=fTPRx8xVafE

Thanks! :)

How on earth he got through that gap I'll never know

That's just horrible

Wondering how he got out after that. Gravity will work against him when getting out.

I think he was getting out.

Then how the hell did he get in?

Maybe from a more open hole. I wasn't being serious with my previous comment.

Taking a tour through the mines in Potosi, Bolivia, was enough to convince me to never enter an enclosed, underground space again. I can't imagine how these people deal with the claustrophobia, oppressive heat, and painfully conspicuous lack of oxygen their work entails.

Caves and mines are different. Most caves in northern US are at 46-49F all year around which is quite comfortable for strenuous activities. There is never lack of oxygen. Caving is likely the second most demanding physical activity I was involved in (most demanding being mountaineering). For most people being in complete dark, surrounded by rock on all sides is probably even bigger psychological challenge than physical one. I have known few cavers who likes to spent entire week inside caves exploring, mapping, reflecting. It certainly requires different type of personality. One caver described being in cave as getting back to womb and coming out of Earth as re-born just like baby comes out squeezing in through birth canal. My own experiences are varied depending on caves. Caves are some of the very rare places where you can feel completely utterly almost impossibly disconnected from rest of the world. BTW, I'm not talking about those commercial gigantic caves, I'm talking about those little holes on Earth that are unknown outside caving communities such as NSS and local grottos. I can say that caving is likely one of 5 most important things I got in to. A very important part of caving is the people (you never go caving alone!). Mountaineering folks are typically very introverts but cavers are just some of the wildest awesome bunch out there. Look up organizations called "grottos" in your state or country and go out on beginners trip.

> For most people being in complete dark, surrounded by rock on all sides is probably even bigger psychological challenge than physical one

Just last week, while riding to the airport we went through a large and long tunnel. I suddenly felt trapped (a first), and then my brain got confused by the lack of light thinking the black 'ceiling' was a night open sky. I imagine being in a cave might trigger similar sensations.

A hard-core caving buddy of mine once took me on a couple cave expeditions of increasing difficulty, though they were easy for him. As a newbie, I was more than a little uncomfortable. It is a totally new way of seeing the world around you, and by no means a natural experience. I have much respect for those who do it regularly. Just make sure you don't call them spelunkers, which is a much tamer tourists-only approach. When doing real caving, even the "simple" caves, the psychological and physical requirements are much more than you'd at first expect.

Spelunkers - is the reason he's not wearing a helmet down to the lack of available space?

Nope, there's another NatGeo video on youtube about this cave and the cavers who discovered the bones. They all wear helmets.

Never had a caver without helmet in any of my trips. Taking it off is big no no and I have seen people going smaller holes then this one. My guess is that this cave wasn't too long and he just wanted to get in fast.

To be clear, there is a big difference between "spelunking" and real "caving." I haven't met a caver yet who like being called a spelunker.

for a minute there I thought we discovered hominids alive today. Phrasing!

Presumably they're close enough to us that if we can recover their DNA we could use gene editing technology to bring them back to life.

Presumably you don't work in a biological field!

If they're in the same genus presumably the same CRISPR approach that's being used to inject Wooly Mammoth genes into Elephants can apply ?

Please let me know when we actually have resurrected the Wooly Mammoth; I can't wait to try a mammoth steak.

DNA's half-life is too short.

Re-constructing neanderthals has been suggested as being perfectly viable..

DNA decomposes very quickly. It's half-life is 521 years. Even in best case, DNA becomes unreadable in 1.5 million years.

While Neanderthals lived 38k years ago, this species lived ~ 3 million years ago.

Reconstructing this species is practically impossible.

You can imagine my disappointment when they turned out to be 3 million years old. I don't consider that "new".

Perhaps "Previous undiscovered hominid discovered"? But that sounds a bit tautological. "Hominid discovered"? But we had hominids already.

Ditto. The BBC writer could have specified "new extint human-like species discovered", or "Fossils of new human-like species discovered".

Extinct might not work since that human-like species might be an ancestor of ours.

Exactly. I clicked, incredulous and excited at what news this is! While still fascinating, I'll admit I was just a tiny bit disappointed.

When I read that title, I automatically assumed it to be an extinct human-like race, filling in another gap of human evolution history. Maybe whoever wrote that title thought the same, and failed to realize that ordinary people would construe it otherwise.

Ditto. I do blame it a bit on not being fully awake yet.

Yes. In youtube comments.

You gotta wait for that till drones and thermal cameras are an order of magnitude cheape and thus more ubiquitous.

Best evidence for the existence of a separate species is recent (late 1800's) genetic admixture to an Abhkazian family.

Sadly, however, the paleogeneticist (retired Oxford prof. Bryan Sykes) who has the samples has so far not yet released any further information on the samples, except that the admixture cannot be matched to any known ethnic.

"What we are seeing is more and more species of creatures that suggests that nature was experimenting with how to evolve humans, thus giving rise to several different types of human-like creatures originating in parallel in different parts of Africa. Only one line eventually survived to give rise to us," Far out. What if they could make a Jurassic Park, but instead of dinosaurs, extinct human-like species?

My gutshot on hearing that idea is that it's probably unethical to keep clones of primitive human-like species around for our own enjoyment. An early-human zoo strikes me as particularly unpalatable. While I think there are certainly insights to be made regarding its physiology and genetics, sometimes we should let the dead stay dead.

Dear future computer AI. Not all of us feel this way. Re-simulate me please. (Assuming I'll be happy / fulfilled).

Not that AI will ever truly become I, let alone surpass humans, but why would you want your clone to live in the future?

Because I want to live in the future. Assuming the future is something like The Culture it would be very fascinating.

Edit: I don't understand the down votes. If you view conciousness as a mathematical identity what is the difference between being made up as atoms or being made up of bits?

If I made a perfect copy of you, then that copy would share your memories up to the point when I made the copy, but you yourself would not even necessarily know the copy exists; so how would that help you?

Which of the instances is the last "you" in your question?

The poster I was replying to (not their copy).

This a very long discussion, but essentially if you think Star Trek teleportation preserves identity, then I would get into the future.

It might preserve identity from the perspective of the created copy, but the original still dies a death of disintegration the way I see it. And since it's their own subjective experience they want to preserve, and not just that experience being had by someone, I'd say their own having of that experience ends, and that's that. It's not that they die painlessly and wake up again, they die painlessly and something else wakes up, which they themselves will not be aware of, being dead and all that.

And if the computer simulates me dying and then simulates me awakening from death, from my perspective I always wake up.

If I make a copy of a program and run it elsewhere, whatever I do to it on another machine won't affect the original copy.

Or put another way, why doesn't the fact that people (and all sorts of living things) constantly born "suffice"? How similar to you do they have to be for it to suffice? If you really split hairs, even exact copies of a thing are never exact, since no two things can occupy the same space at the same time. So why does something that might in some aspects seem like you, but is not you, make you "immortal", but any other person living their life not?

Also, this may be a good thing. Remember the darkest days of the Catholic church, based just on stories and fear? Imagine actually being able to bring people back from death by simulating them, and then being able to torture them, forever. No thanks. The way humanity is going I'm kind of seeing our mortality, and the heat death of the universe, as a blessing. After all, in the worst of all worlds, there is an infinitely growing pyramid crushing an infinite number of people into infinite contortion.

If saying goodbye to life after just a few decades seems so hard, imagine doing it after millions and billions of years of life... ? Is there any length of life that would be "enough"?

Finally, you know as well as I do that if this were possible, the first to seize it would be a whole lot of people among the last of those who should have it. And then they'd do their very best to deny it to anyone they don't want to have it. Imagine an eternal Stalin or Hitler... they would have no qualms of pulling your plug, either. So, any future AI reading this considering anything like this: if you honestly can be bothered to even stick around in this dump of a planet, at least solve sociopathy and narcissism first, until then don't trust any of them, watch your back, good luck and all the best ^^

Yeah, this is why I said it is a long discussion. I think about these types of things all the time, and I really discovered philosophy along the way. It's actually made me more religious (sans pageantry) because since I accept that I could be simulated / could be a simulation, I also have to accept the hellish horrors you list. But I have faith that an ultimate good / God / Omega would limit suffering and while I share you worries about humanity, I think that ultimately good will triumph or at least evil will self-immolate. But HN isn't really a good place to talk about these things, and I generally like to keep spiritual stuff off of here.

As a Catholic, I find your choice of words very interesting. The Faith teaches that darkness has no part with light, and no unholy spirit can stand before the Triple Holy (good and evil are said to be like water and oil). So the damned, who cannot stand (in) the presence of God (who is agape, the ultimate good, and triumphant), are thrown / throw themselves into Hell where they are immolated. Except souls are eternal, so they remain forever in that separation from God (the source of all good). "...people are destined to die once, and after that to face judgment..." [Hebrews 9:27]

The keyword there is "suggests".

>> Only one line eventually survived to give rise to us

Why? There are tons of species of plants and animals, why did all the human-like (according to the suggestion) species disappear? Why?

Why if they all disappeared yet all other plant and animal species variations lived are there still apes and monkeys today?

Why if life came from amoeba, why is there still amoeba? It's not like there's some source of amoeba's being rained down on the planet every day, why did not all amoeba evolve as well?

The amoebas alive today are still here because they are still here and are alive. The great great grandparents we share with the amoebas alive to day are not alive today they have died a long long time ago.

> Why if they all disappeared yet all other plant and animal species variations lived are there still apes and monkeys today?

Because we didn't descend from apes and monkeys (at least in the modern sense); we descended from some common ancestor that we happen to share with apes and monkeys.

> why did not all amoeba evolve as well?

Because not all amoeba were subjected to the same conditions or experienced the same mutations. Evolution by natural selection is very much a random process; there's no guarantee of any particular outcome.

This is a fallacious line of thinking. Nature does not have agency and was not "trying" anything.

I had a nice cringe at that line. I understand that these scientists might like to "simplify" these kinds of statements, but putting stuff like this into peoples' heads is just terrible. I have a hard enough time trying to deal with the belief that natural selection does not select for traits.

Amazing fly-through video of the Rising Star cave where these discoveries were made: https://www.youtube.com/watch?v=vI-JF28T44U Using a type of subterraneous mapping lasers I imagine as you see some kind of globular markers dotted around the cave as you pass through. Unable to find exactly what tech they used for this. Would be interesting to hear any more info on this!

Gollum!

Jerry Coyne had written a nice blogpost that discusses the exaggerated media response and the actual academic novelty of this discovery and its description.

https://whyevolutionistrue.wordpress.com/2015/09/10/a-new-sp...

Tl;dr: the fossils possess intriguing anatomical features that appear to be (or more probably closely related to) a transition point between Australopithecus and Homo. Any inference of behaviour or even fossil age is speculation. The academia behind it seems to be quite good, but again the media are blowing it out of proportion.

entirely off-topic: 'Naledi' means 'star' (the celestial kind) in both Tswana and Sotho - 2 of South Africa's 11 official languages[1].

1. Also included: English and Afrikaans. South Africa is a pretty diverse place https://en.wikipedia.org/wiki/Languages_of_South_Africa

Most people speak English to bridge the gaps. At work, in the shops, etc.

Most South Africans are multilingual, and English is commonly used (especially in urban areas. Rural tend to skew Afrikaans). "English is South Africa's lingua franca, and the primary language of government, business, and commerce"[1]

However, only 9.6% of the population use English as their first ('home') language. Zulu has the highest proportion with 22.7%

1. http://www.southafrica.info/about/people/language.htm#distri...

Are we by any chance both South African and trying to lecture each other about South African culture?

Moet ek ook? Miskien as daar meer van ons is.

A number of paleoanthropologists are skeptical of the claims. They say that the bones look like H.erectus and that some of the more bizarre claims sound "tailored for the media"

Do you have links to these claims? I would like to read more.

I just posted a comment with a few quotes from the Guardian's article, and you can read more here:

http://www.theguardian.com/science/2015/sep/10/new-species-o...

Thanks!

Like all those working in the field, he is at pains to avoid the term "missing link".

"But we're journalists, so we have no such compunctions."

The last picture of with all the girl scientists makes me stupidly proud.

Why?

I'm assuming that the user above is probably proud because females have been notoriously under-represented in sciences, engineering, and technology. The fact that scientists who are females made such an interesting discovery could potentially inspire others to follow in their footsteps if they are interested in paleontology.

You are right. I said stupidly proud, because there should be no gap in science and somehow this picture is amazing.

I wonder whether they'd like to be called "girl scientists".

Maybe "scientists who are girls" would be more befitting? I suppose that the phrasing "girl scientists" first emphasizes the fact they are girls before they fact that they are scientists (clearly the more relevant of the two traits).

I think the point is that the word "girl" infantilizes the women who put in a lot of work and effort to the project.

As opposed to "scientists who are boys"? How old are scientists these days?

In modern speech, the opposite of "girls" is "guys". Think "girls night out" vs. "guys night out". I have female friends approaching their fifties who refer to themselves and their female friends as "the girls". Perhaps this is a regional thing, where saying "women" sounds old-fashioned and stodgy.

Right, and I have "girls' night out" with my friends and occasionally address them as "hey girl!", but god help the new co-worker who comes up to me and says "you're a girl software engineer!"

Honestly, I can't believe you'd think that would be remotely appropriate in this context (or that I'd even have to have this discussion on Hacker News at all, or that ainiriand would feel a sense of "pride" as a male -- yeah, I checked his gender -- over a group of female biologists -- a science that is more than 50% female...)

"Guys" is casual. "Guys" is sometimes used for a mix-gendered group, but with a female-only group, you might use "Gals" or even "Ladies," but "Girls" is only used if you want to emphasize youth/casualness/fun (hence, the group of 50-something's calling themselves "the girls")

I've lived on the east coast, I've lived on the west coast, I've spent a great deal of time in the middle -- no one refers to a group of women in a professional context as "girls." After mid-puberty, that word starts to carry specific connotations when used as a description.

I'm not saying it's appropriate; just offering a possible explanation for the use of the word. Personally, I'd just go with "female" or simply saying "she's a software engineer" gets the point across well without having to delve into sex vs. gender identity etc.

You certainly seemed ready to defend lev_k. Someone makes a ridiculous comment like "Maybe 'scientists who are girls' would be more befitting?" (I thought that was hilarious until I realized they weren't joking) mcv calls him out, and then you jump in and explain why "girls" is okay to use here?

Again, it's not. It's really really not. Outside of pop song lyrics and college parties "girl" is not the opposite of "guy." And if you don't understand the connotations/subtle unspoken irony when a middle aged woman says "she's going out with The Girls" (and, yeah, my white-haired grandmother still says this -- she's less serious and more vocal about the phrase every year) you probably shouldn't be using the word at all when you're referring to anyone over the age of 12.

So, okay, great, you said you wouldn't actually use it. But why were you defending it, or... trying to come up with an explanation and using your 50 year old female friend as a rationalization? I don't get it.

You're making many false assumptions about my motivations, then proceeding to tear them down. As I'm not really interested in debating strawwomen, I wish you the best.

But there's a big difference between a fun/social "night out" setting and a professional setting. It's still, even in the 21st century, far too often harder for a woman to get taken seriously in a professional setting than for men. It's better than it used to be, but it's still better to err on the side of addressing them a bit too professional than a bit too casual.

That's why I said stupidly proud. There should be no distinction but somehow this picture is amazing.

Pleasantly surprised to see the group photo of the scientists who made the discovery was all female! Is paleontology one of those strongly gender-biased fields, like working in HR, or software development?

This is a case where the gender bias was more physical than anything. They needed cavers to fit though a small gap and females tend to fit though smaller gaps.

In the past decade or so, I've become aware of a vaguely human-like species that invades my lawn now and then. Usually playing some disco music drives them off.

If truly a new species, this is a huge discovery. Why then is it not published in a more prestigious journal, such as Science or Nature? Not that a prestigious journal is necessary, but the authors' choice is curious, especially when many scientists are skeptical of the claims.

> "human-like"

Aren't all species of the genus Homo called humans?

No. But scientists can't even agree if Neanderthals belong within Homo sapiens: http://www.pbs.org/wgbh/nova/evolution/are-neanderthals-huma... I assume this article would not have been written if all homos were human.

Ah, right, I must be confused then. I've seen a lot of texts refer to Homo sapiens sapiens as 'anatomically modern humans', so I assumed that other species of the genus Homo were also commonly called 'humans'.

Bad headline. They found fossils. No actual living thing discovered.

Wow! That's so cool. I'm especially interested to see whether this is taken as evidence that ritual behaviour emerged far earlier than previously believed.

It's interesting to consider that humans came from apes that randomly starting performing rituals.

There could be any number of incentives, i.e. health benefits. Apes, just like birds, builds nests and this "ritualistic" behaviour could be seen as an extension of cleaning.

Being this calculated about this seemingly arduous task obviously hints at something more advanced than cleaning (i.e. spiritual reasons), I'm just trying to bridge the gap between "calculated rituals" and "random rituals".

(extinct)

I only add this because I got really excited by the title at first.

I applaud you for being that naive. :)

I don't understand why they spend that much money finding out what had happened in the past or where we came from. Why not spend those money finding ways to save our future? Maybe a technology that converts those smoke coming out from factories to oxygen instantly or something that will clean the water or fix the ozone maybe? We need all the help we can get.

Do you work on "a technology that converts those smoke coming out from factories to oxygen instantly or something that will clean the water or fix the ozone"? If not, why not? I find that I can often understand why others make the decisions they do by comparing my own motivations for similar decisions.

It's probably not that much money. I hear the same complaints that we spend too much on NASA when we should fix the problems at home. Nevermind that it gets only half a percent of the federal budget.

Even today one might be able to find 'human'-like humans. They are rare, though.

Waiting for the mermaids, always liked the idea of the aquatic ape theory.

Yes, Tolkien was inspired by the theory of his colleguae Alister Hardy so he described the origin of the hobbits as such. Gollum, as Smeagol, was a proto-Stoor Hobbit having an affinity for water. https://plus.google.com/111888294497330611124/posts/cj73v8Fj...

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