
Oldest Human DNA Yet Found Raises New Mysteries - Irene
http://www.nytimes.com/2013/12/05/science/at-400000-years-oldest-human-dna-yet-found-raises-new-mysteries.html?_r=0
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terabytest
It's so mind boggling to think that the "Homo Erectus" existed as far back as
1.8 _million_ years ago, yet most of our recent (and known history) happened
in the last 5000 years, and we see that as a huge evolution.

What the heck happened between 1 million years ago and now? The human race
changed a lot and matured very much, but it's so incredible that such a big
evolution only happened in the last few thousand years and the rest has taken
hundreds of thousands of years.

~~~
simonh
Agriculture. It's a several orders of magnitude improvement in the population
density an area can support, which makes population centres possible, which
makes specialisation viable, which makes everything else possible. If someone
had developed agriculture 100,000 years ago, we'd currently be about 90,000
years more advanced than we are now.

Agriculture appears to have been developed independently in the Middle East,
China and Americas about 10,000 years ago, but I and some others believe there
was more dissemination of ideas, mainly via individual travellers or small
groups of travellers, than conventional historians take into account.

~~~
gizmo686
This seems to beg the question of what caused agriculture to appear. Although
given that it did appear, your explanation seems like a plausible explanation
of how it spread and led to the rapid progress we have seen since.

A boring answer to this question is that it was simple incremental changes
driven by random mutations and natural selection (eg. evolution). For example,
we might have started to occasional plant the seeds of plants as we found
them, which could become us regularly doing so. Then we might have started
moving the seeds to more central locations, and eventually arrive at
agriculture as we know it today. These adaptations may have started before
homo-sapiens. If it happened long enough before (so that there is another
species with a common ancestor that did this), we could check this by looking
for agricultural tendencies in species related to us (If anyone is aware of
research on this hypothesis, please post).

A more interesting hypothesis is that agriculture was the result of an abiotic
change. Instead of gradually developing agricultural tendencies, we
'immediately' became agricultural following some other event, such as a change
in climate. This seems to be consistent with my understanding of climate
history, which puts us in a relatively short window of nice climate.

~~~
DougWebb
10,000 years ago is the end of the last ice age, before which climates were
shifted, sea levels were lower, and most of the land humans tend to like to
live on (near sea level) are now deeply submerged.

We think agriculture and city-building started around that time, but it's
possible we just haven't found older evidence because it was destroyed when
the ice age ended and sea levels rose.

It seems incredibly arrogant to me to think that our ancestors, who were
virtually identical to us much of those million+ years, required at-minimum
hundreds of thousands of years to figure out what seeds are and how to make
them grow. These are people who knew how to live off the land and were far
more familiar with plants and animals than most of us could dream of being.
These people invented astronomy, art, religion, clothes, tools, fire. They'd
notice that plants produced seeds, that seeds wound up on the ground, and that
new plants grew where the seeds fell.

~~~
simonh
I don't buy the atlantis "they're all under the sea" theory at all. We are
expected to believe that they only built cities by the coast and none at all
along rivers or round lakes? None of these civilizations spread to areas where
the sea level has not risen so much? Far too contrived for my tastes.

Il flip your arrogance accusation around. These people developed agriculture
and even cities tens of thousands of years ago, yet none of them managed to
put together a sustainable survivable civilization? None of them managed to go
from basic agriculture to even slightly more advanced agriculture that would
have launched them on the track to specialization, even given hundreds of
thousands of years in which to try? Why not? What was wrong with them?

To a hunter-gatherer, which is a nomadic lifestyle, cultivation in a fixed
area for long enough to both sow and later reap a crop is not at all obvious.

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batbomb
They have more on this on the Nature podcast. I also highly recommend
listening to the Nature podcast. It's free, and they usually interview authors
of these articles, and it's presented in an elevated fashion that you won't
get by reading the NYTimes.

[http://www.nature.com/nature/podcast/](http://www.nature.com/nature/podcast/)

~~~
jrkelly
That NYT author, Carl Zimmer, is also pretty solid. He's doing a twitter Q&A
now if you want to ask him Qs:
[https://twitter.com/carlzimmer/status/408327412250734592](https://twitter.com/carlzimmer/status/408327412250734592)

~~~
batbomb
Yeah this article is actually quite good, better than most science articles
I've read from most major media outlets. I wasn't meaning to belittle this
specific article, but I thought I'd point an actual interview with author
Svante Pääbo.

Also, again, I think the Nature podcast is by far the best podcast for general
science, so if "[people] fucking love science", I'd recommend listening to it
weekly over liking a facebook page, especially as they cover their weekly
publication on a slightly more accessible level. Also, Science (the
periodical) has a pretty okay podcast too.

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leot
The age of this DNA reinforces just how much of what we value today about
"what makes us human" (creativity, intelligence, language, etc.) has lots to
do with the knowledge accumulated via our culture, and relatively little to do
with genetic differences.

Whenever someone talks about how smart we are genetically, ask yourself if
this is the kind of smart we were 10,000+ years ago.

~~~
gizmo686
The way I think about it is that there is a tipping point in intelligence
where a species can build on its own discoveries at a much accelerated rate,
similar to the concept of a singularity in AI. As 10,000 years is not that
long from an evolutionary perspective, we are about the dumbest that a species
could possibly be in order to reach that singularity point, otherwise we would
have done it earlier.

Of course, this ignores factors such as non intelligence based adaptations
(such as thumbs), antibiotic factors (climate). It also ignores the facts that
intelligence is composed of many components, and our singularity might have
happened after an improvement is some metric that does not contribute much to
overall intelligence. For example, the ability to speak does not make an
individual animal more intelligent, but it does facilitate the accumulation of
intelligence through generations.

~~~
leot
Why do we need a tipping point?

Proposal:

1) Human progress arises from the development and improved use of
tools/technology (and I'm including concepts like "if", as well as skills, as
kinds of technology)

2) Our tool use abilities interact multiplicatively/geometrically. E.g., [what
I can do with a hammer and a shovel] is not the sum of the [things I can do
with hammers] and [the things I can do with shovels]

3) Our tool-use-abilities started meagre

4) Tool use is not uniquely human, but humans are better at it

5) Accidents of history and human development have allowed for the
accumulation of tools (agriculture, e.g.)

... this "explanation" (or what have you) yields exponential growth curves
that, I propose, would look very similar to those of humans. If there was a
"tipping point" perhaps it was (5) -- the introduction of some substrate upon
which cultural knowledge could grow.

~~~
maxerickson
I think language works as a tipping point in that sequence. For technology to
interact as you say, it has to spread easily.

~~~
leot
Why do we take as the default hypothesis that language is, as you seem to be
implying, a monolithic "thing"?

A more plausible hypothesis seems to me to be that language itself is
constituted _by_ a suite of cultural tools/skills. A language with a very
limited vocabulary (especially one restricted to largely unhelpful words, e.g.
"Justin Bieber", or "toe wart") is much weaker than one that has benefited
from decades of cultural and generational digestion and iteration (i.e., a
language that includes concepts like "however", or "on the condition that", or
"art", or "gravity").

------
tokenadult
As another comment says, the author of this New York Times article, Carl
Zimmer, is a very solid science writer who knows a lot about evolution. I have
occasion to discuss human population genetics with psychologists who study
behavior genetics, and when population genetics issues come up in those
discussions, some of the new discoveries are surprising even to them. It's
hard for reporters, us, and even the working researchers to keep up with the
new findings in human population genetics. I'll share a finding here that
surprised some researchers I discussed it with this week.

The first human genome to be sequenced was that of Craig Venter, who would be
called a "white" man in the United States. The second human genome to be
sequenced was that of James Watson, who is also regarded as "white" in either
the United States or Britain. One of the first dozen or so human genomes to be
sequenced was that of Korean scientist Seong-Jin Kim,[1] and his genome, even
though "Asian," is more similar to Venter's than Venter's is to Watson's, and
more similar to Watson's than Watson's is to Venter's.[2] Even though lineages
are traceable in broad outlines by looking at human genes, there are quite a
few human beings who resemble someone in someone else's group more than they
resemble people in their own group. "The fact that, given enough genetic data,
individuals can be correctly assigned to their populations of origin is
compatible with the observation that most human genetic variation is found
within populations, not between them. It is also compatible with our finding
that, even when the most distinct populations are considered and hundreds of
loci are used, individuals are frequently more similar to members of other
populations than to members of their own population. Thus, caution should be
used when using geographic or genetic ancestry to make inferences about
individual phenotypes."[3]

So what's going in these studies of early hominid DNA is that we necessarily
have tiny sample sizes, and we actually have no idea how much genetic
variation there was in the population we call Neanderthal, how much in the
population we call Denisovan, and so on. We will want to sequence as much
ancient DNA as we can, and meanwhile sequence more modern human DNA from more
people from more places around the world. But we won't be able to trace back
the ancestry relationships unerringly, no matter what we do.

[1]
[http://genome.cshlp.org/content/early/2009/05/26/gr.092197.1...](http://genome.cshlp.org/content/early/2009/05/26/gr.092197.109)

[2] [http://www2.webmatic.it/workO/s/113/pr-1611-file_it-
Barbujan...](http://www2.webmatic.it/workO/s/113/pr-1611-file_it-
Barbujani%20Pigliucci%20CurrBio.pdf)

[3]
[http://www.genetics.org/content/176/1/351.full](http://www.genetics.org/content/176/1/351.full)

~~~
qubitsam
Ok, I have to ask this, and I apologize in advance for it being out of topic.

How on earth are you well informed on so many topics spanning different fields
of science and literature? Your comments are amazingly well informed, and I
would like to know how you do it.

~~~
cdr
He knows how to sound informed, which is the important part. Large walls of
text, big words, selective citation of valid sounding papers.

~~~
trentnix
He's probably also disciplined enough not to sound off on topics that he
doesn't know anything about.

I was consulting (software) at a client site and one of the employees at the
client remarked that I seemed to know everything about everything. I just
replied that it was a trick - I only talk about the things I'm informed on,
and when a question came up on a topic I didn't know anything about, I just
redirected the conversation back to my expertise. I had a hammer and worked
hard to make everything a nail. :)

~~~
berntb
So... when you're not a consultant with a need to impress people, you instead
redirect the conversation to subjects other people know, which interests you?
:-)

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delicious
fun fact: Denisovan sounds a bit like Dennis, doesn't it? Surely a
coincidence... The remains were found in the Denisova Cave, which was named
after a hermit who live there, Denis
[http://en.wikipedia.org/wiki/Denisova_Cave#History](http://en.wikipedia.org/wiki/Denisova_Cave#History)

------
bushido
Simpler explanation/story (Pun intended) == Battlestar Galactica

