Discoverer of Lucy skeleton hopes to find what made us human

Australopithecus afarensis, 'Lucy'
A reconstruction of a female Australopithecus afarensis. Image: Wikimedia Commons.

This month marks the 40th anniversary of the discovery of Lucy, the partial skeleton of an apelike creature that walked upright 3.5 million years ago. The 1974 find would forever change humanity's understanding of where our species came from and how Homo sapiens evolved.

Donald Johanson is the paleoanthropologist who found Lucy's remains in the Hadar area of central Ethiopia. He and his colleagues named the fossil after the Beatles song "Lucy in the Sky With Diamonds," which played repeatedly the night he made the discovery.

These days Johanson serves as the founding director of the Institute of Human Origins at Arizona State University. He spoke to the Los Angeles Times about Lucy's impact on paleoanthropology and what he hopes to find next.

Q: Before Lucy, what was the accepted narrative of human evolution?

A: In the early 1970s when I first went into the field, there was a tug-of-war going on between Europe and Africa. Most people thought our most primitive origins were in Africa, but where we really became human was Europe.

Q: How did the discovery of Lucy change that?

A: She shifted, very dramatically, anthropologists' view of where we obtained our human features. She showed us it happened in Eastern Africa, and more specifically in the Afar region of Ethiopia where she was found.

She also allowed us to say conclusively that upright walking went back as much as 3.5 million years. That was a major leap in our understanding of the sequence of events of .

Q: How do you know she walked upright?

A: Because we had her pelvis. It's a very rare discovery to find a pelvis, and hers is so strikingly different from the pelvis of a four-legged animal like a chimp. A four-legged animal has a high narrow pelvis with the hip bones facing forward. Our pelvis is squat and wide with the hip bones forming a bowl.

Lucy's body still had relatively short legs and relatively long arms, which is the kind of anatomy we see in more tree-living or arboreal species. So she was an important bridge for us between more ancient sorts of things and more modern sorts of things.

Q: Why was upright walking an evolutionary advantage in Lucy's time?

A: Walking upright had the advantage of freeing the forelimbs from locomotor needs, allowing them to be used for other things, like carrying food back to a home base and sharing it with members of one's own tribe or band.

We don't know what all the benefits were, but it was obviously a major landmark breakthrough. The apes have been in decline since as long as we can remember, but there are, what, 8 billion of us today?

Q: How has the science of continued to change since Lucy's discovery?

A: When I entered the field, we had maybe six or seven different Homo fossil species. Now we have 15 or 20. So what has changed is that we understand it was not a straight line from the most ancestral species to modern humans, that there were many false starts.

Q: Are there major holes in the story of our origins that you would especially like to see filled in?

A: At the Institute of Human Origins we are working to answer the specific question: What are the evolutionary foundations of modern humans?

The features that distinguish us from all other animals are symbolic language, our cooperation, and a culture that allows us to make cumulative developments that no single individual could make alone. So, how did all of that come about?

Q: Anything else?

A: I'd also like to know where our particular genus came from - the genus Homo. Everyone in the world is Homo sapien, but there were other, earlier Homos too. Lucy's species, Australopithecus afarensis, died out about 3 million years ago, but the oldest Homo evidence we have is from 2.3 million years ago. That means the emergence of our own genus happened between 2.3 and 3 million years ago, and that is where people are looking.

Q: Is there a specific geological place where you think the answer might be found?

A: We have people who have planned expeditions to strategically target geological strata from the 2.5- to 3-million-year period in the Afar region of Ethiopia north of where Lucy was found, and in Kenya.

These layers are devilish to work in because they don't have many fossils in them, but they have some fossils, so there is a possibility that something can be found in there that could finally link Australopithecus with Homo.

Q: Some people feel that the world has been picked over, and there is nothing left to discover. Do you agree?

A: One of the changes in paleoanthropology that is so healthy is a switch from discovery-driven to a much more introspective level of scientific research.

There are thousands of fossils in vaults throughout the world that have only been superficially studied. We can now look at trace elements and see what diets were like, or use CT scans to look at tooth formation and what it can tell us about life histories.

We also have geological deposits throughout Africa that have not been thoroughly examined and I think new discoveries will be made and be surprising.

As I tell my students, you are only limited by your imagination.


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JVK
Nov 05, 2014
Excerpt: "We can now look at trace elements and see what diets were like, or use CT scans to look at tooth formation and what it can tell us about life histories."

The link from diet to tooth formation and life histories is clear in species from nematodes to modern humans. Nutrient-dependent RNA-directed DNA methylation and RNA-mediated events link amino acid substitutions to cell type differentiation that is controlled by the metabolism of nutrients to species-specific pheromones. The pheromones control the physiology of reproduction and fixation of the amino acid substitutions.

Nutrient-dependent/pheromone-controlled adaptive evolution: a model. http://www.ncbi.n...24693353

Excerpt: "Differences in the behavior of nematodes are determined by nutrient-dependent rewiring of their primitive nervous system... Species incompatibilities in nematodes are associated with cysteine-to-alanine substitutions... which may alter nutrient-dependent pheromone production."

Nov 05, 2014
jvk Hands down winner of the most narcissistic poster here.

JVK
Nov 05, 2014
Thanks. Have you ever considered addressing the data? I think theorists are the narcissists. They are so convinced that their ridiculous theories are supported by experimental evidence of biologically-based cause and effect, that they ignore any evidence that refutes their claims -- and make stupid comments.

Does evolutionary theory need a rethink? http://www.nature...-1.16080


Nov 06, 2014
The cute image of Lucy we see in the photo is the product of a professional studio for special effects with increased quality control. Wizards of this studio make a compilation of several bones with human and simian origin to create computer aided desired image of our distant hypothetical ancestor.Recent history knows many such artistic experiments. Sensationаlists and careerists eager for scientific recognition and fame, often make compromise with his conscience and thanks to such unscientific practices today many people have misconceptions about the world we live in.

Nov 06, 2014
Very timely article, since it ties in with the concurrent article on cultural transmission baboons, the only 2nd case observed.

Evidently cultural transmission, one of Johanson's key traits, is a basic trait in primates, that sometimes gets lost. And chimps are much more specialized than baboons and humans. (E.g. knuckle walking, which transformed the generic hands that we share with baboons and other apes.).

Too bad about the problem of fossilization in the key sediments. But we are getting there, full resolution on human heritage is a possibility.

Nov 06, 2014
Oops, sorry Vietvet, seems voting can't be revoked. I didn't see the only sane comment among the anti-science medievalists. You'll have 5 stars from me, even though I think all creationists are egocentric: they have being lied to, and sunk cost and (for comment posters on science threads) Dunning-Kruger doesn't allow them to check out even a web encyclopedia for the facts.

As a student said the other day, 'there is nothing to debate between an established fact and denialists. It's like discussing the existence of Canada.' (Re the Non-Discovery Non-Institute trying to hijack the good name of a university for anti-science activities.)

I'll let them lie. It condemns their nefarious, immoral religions, and they are welcome to that.

JVK
Nov 06, 2014
Binding thermodynamics of a glutamate transporter homolog http://www.nature...548.html

The article helped establish how excitatory amino acid transporters link the conserved molecular mechanisms of RNA-mediated amino acid substitutions to brain development and behavior. See also: http://www.scienc...14001362

If you don't understand how protein folding is biophysically constrained, you should quit touting pseudoscientific nonsense and learn why mutations cannot possibly lead to the evolution of biodiversity.

It makes no sense to keep acting as if others know nothing about ecological variation and ecological adaptation just because you know nothing about biologically plausible links from the epigenetic landscape to the physical landscape of DNA in the organized genomes of species from microbes to man. Your displays of ignorance benefit no one.

Nov 06, 2014
If you don't understand how protein folding is biophysically constrained, you should quit touting pseudoscientific nonsense and learn why mutations cannot possibly lead to the evolution of biodiversity
and if you don't comprehend that your own model causes mutations then you should remove yourself from the serious discussions of science
when you claim that mutations are pseudoscience and they cannot lead to the evolution of biodiversity, then you are saying that your own model cannot lead to the evolution of biodiversity
remember.. I asked
DOES your model make any changes to the nucleotide sequence of the genome of an organism, virus, or extrachromosomal genetic element?
This is a yes or no answer
(this is the DEFINITION of mutation) to which you answered
YES!
--Thanks for asking
so this proves you are not only incapable of even learning a new word in your own chosen fields lexicon
but pusing pseudoscience

when jk makes up definitions, she promotes PSEUDOSCIENCE

Nov 06, 2014
It makes no sense to keep acting as if others know nothing about ecological variation and ecological adaptation just because you know nothing about biologically plausible links
and yet... this has never stopped you from posting here!

again, when you make up your own kohl-slaw word salad with your own special adapted meanings for words, you are NOT doing science, you are promoting PSEUDOSCIENCE
http://sci-ence.o...-flags2/

and there is NO science in the creationist movement: https://en.wikipe...Arkansas
so continuing to promote a failed faith based ideal is nothing but proving empirically with your own words that you are:
1- a pseudoscience troll
2- blatantly stupid
3- ignoring empirical evidence for a faith
4- not a legitimate scientists

you have also lied and claimed to have decades experience in diagnostics medicine although you never finished college and this is a violation of the law

jk=liar=pseudoscience

Nov 06, 2014
Very timely article, since it ties in with the concurrent article on cultural transmission baboons, the only 2nd case observed.
@Torbjorn_Larsson_OM
are you talking about this one?
http://phys.org/n...firstCmt
and the linked study
"Cultural evolution of systematically structured behaviour in a non-human primate," N. Claidière, K. Smith, S. Kirby, J. Fagot. Proceedings of the Royal Society B, 5 November 2014
http://dx.doi.org...014.1541

excellent reading
i went looking after i read your post.. so thank you for the heads up

I am sure Vietvet understands, too... we all make mistakes, especially when the comments are flooded with spam, pseudoscience like jk and creationists stupidity like viko

Thanks again

Nov 07, 2014
How can be restored the image of an animal or ancient man by several found bones and how they can be reliably dated? In this case, in addition to the imagination of what else can rely researchers? Often after isotopic analysis of differnt bones or tissues from the same animal or humanoid, the results are startlingly contradictory.

Nov 07, 2014
How can be restored the image of an animal or ancient man by several found bones
@viko-tard
believe it or not, we know a lot about anatomy these days
you should read up on forensics
how they can be reliably dated?
first, you usually have to introduce yourself, and then it is good to get the fathers permission... and make sure you are proper and don't act out because that may indicate a poor background and then you can kiss reliability away
https://en.wikipe...arbon-14
http://science.ho...-142.htm
http://www.tim-th...ric.html
In this case, in addition to the imagination of what else can rely researchers?
complete gibberish and nonsense
the results are startlingly contradictory
fallacy based upon delusion and faith based stupidity
refusal to learn only means you are stupid, not some faith hero

try learning science

JVK
Nov 07, 2014
Small Proteins Can No Longer Be Ignored http://www.ncbi.n...4166647/ Excerpt: How do small proteins evolve?

RNA: The genome's rising stars http://www.nature...443-127a Excerpt: "In the absence of a rich body of literature, ideas are often exchanged at conferences on RNA, epigenetics and genomics."

http://perfumingt...bmit.y=0 Search Results for: RNA-mediated Number of Results: 133

I will attend a pre-conference poster session presentation next week where I expect to learn more about nutrient-dependent RNA-directed DNA methylation and RNA-mediated amino acid substitutions that differentiate cell types manifested in morphological and behavioral diversity in species from microbes to man. The link from the pheromone-controlled physiology of reproduction to chromosomal rearrangements is also becoming clearer.

What will others learn between now and then?

JVK
Nov 07, 2014
Exploding genomes and chromosomal rearrangements via RNA-mediated events
http://perfumingt...-events/

"It is like the genome just exploded and then was put back together," he said. "Up until recently, it has been impossible to determine how one human chromosome could be aligned to any gibbon chromosome because there are so many rearrangements."

Is the explosion of the genome in gibbons akin to the "big bang" theory in the context of how biodiversity arose?

If not, the challenge to theorists is to explain why they accept the "big bang" theory but not the biological facts about nutrient-dependent pheromone-controlled RNA-mediated events that link chromosomal rearrangements to biodiversity via conserved molecular mechanisms.

Instead, they accept what may be the most ridiculous theory ever invented and defined by population geneticists who knew nothing about RNA-mediated events.

JVK
Nov 07, 2014
Landscape and variation of RNA secondary structure across the human transcriptome. http://www.nature...946.html

"These results highlight the potentially broad contribution of RNA structure and its variation to gene regulation."

This is what viko_mx and I have been trying to convey to the anonymous fools and idiot minions of biology teachers like PZ Myers who participate in discussions like this, but repeatedly add only pseudoscientific nonsense. They willfully prevent intelligent discussion because they cannot grasp any aspect of biologically-based cause and effect.

Only theories make sense to them -- and only because they were taught to believe in them by others who were taught to believe in them -- and therefore never attempted to find experimental evidence that linked physics, chemistry, and conserved molecular mechanisms to biodiversity.

Theories about mutations are all mental midgets can think about.


Nov 07, 2014
@jvk
"Theories about mutations are all mental midgets can think about."

The only mental midgets here are you and viko mx with your creationism pseudoscience.

JVK
Nov 07, 2014
Thanks for providing yet another example.

Others, for comparison, see the review of the book I co-authored in 1995, or anything else I've published since then.

http://www.jstor....83232157

Nov 07, 2014
I will attend a pre-conference poster session presentation next week
you really should try getting an education first... and buying a dictionary
What will others learn between now and then?
besides that you lie and that you cannot comprehend the basic terms and words used in biology so you make up your own definitions?
Instead, they accept what may be the most ridiculous theory ever
there is more evidence for evolution than even the BB
also- your own model that you WRONGLY think is the answer to everything is a PART of evolution theory, supporting it's foundation with proof of beneficial mutations, moron
Theories about mutations are all mental midgets can think about
i wouldn't call you a mental midget... that is far to nice a description
your model causes mutation and you've even admitted as much!
so arguing against mutation only means you are:
1- stupid
2- against your own model

Nov 07, 2014
They willfully prevent intelligent discussion
lets examine this statement and see WHO is pushing pseudoscience
jk says
Theories about mutations are all mental midgets can think about

[kohl-slaw nonsense] seems more appealing than an alternative in which mutations somehow lead to the evolution of biodiversity

If you don't understand how protein folding is biophysically constrained, you should quit touting pseudoscientific nonsense and learn why mutations cannot possibly lead to the evolution of biodiversity
lets stop there for a moment for impact

now... remember when i asked
DOES your model make any changes to the nucleotide sequence of the genome of an organism, virus, or extrachromosomal genetic element?
This is a yes or no answer
(this is the DEFINITION of mutation) to which you answered
YES!
--Thanks for asking
you do NOT comprehend terms and definitions in your chosen field

so you are now promoting PSEUDOSCIENCE and stupidity

Nov 07, 2014
cnt'd
so what we can see above is blatantly clear:
kohl and her blatant stupidity supports MUTATIONS, but only with her model

apparently, mutations in ANY other model are argued against out of sheer stupidity because she does NOT comprehend the science behind it

when she argues that
Theories about mutations are all mental midgets can think about
this is a direct self deprecating comment that shows the fallacy of jk's blatant creationist and delusional religious based intentions which affect her by not allowing her to see reality

Pseudoscience is a claim, belief or practice which is falsely presented as scientific, but does not adhere to a valid scientific method, lacks supporting scientific evidence or plausibility, cannot be reliably tested, or otherwise lacks scientific status.

when you IGNORE the lexicon of a field to make up your own terms and conditions, like jk does
YOU PROMOTE PSEUDOSCIENCE
http://sci-ence.o...-flags2/

JVK
Nov 07, 2014
A new angle on infertility http://medicalxpr...ity.html

The article extends my model of nutrient-dependent RNA-directed DNA methylation and RNA-mediated amino acid substitutions to a mouse model of pheromone-controlled reproduction. An induced mutation revealed how a Cys429 to Ser amino acid substitution led to specific organ defects, not to the evolution of biodiversity.

1) The "...C429S mutation revealed that b-catenin possesses an intrinsic capacity to fine-tune Wnt/b-catenin signalling in vivo."
2) "...human and mouse b-catenin proteins share 100% amino acid sequence identity..."
3) "The Wnt4/b-catenin pathway is indispensible for female sex determination32,33 and is also essential for subsequent ovary differentiation11."

Mutations perturb protein folding; amino acid substitutions stabilize it, which is how they link the epigenetic landscape to the physical landscape of DNA in the organized genomes of species from microbes to man.

Nov 07, 2014
Mutations perturb protein folding; amino acid substitutions stabilize it
and like a complete idiot you go on about mutations again calling them negative all the time while ignoring:
1- your own model which CAUSES MUTATIONS
2- Lenski

you only dig your own hole deeper, and your kohl-slaw doesn't work with people educated and experienced in the biological field

you are only saying that you do NOT comprehend what is going on because you choose to interpret the evidence based upon your faith/religion and your ego, which causes you to fail to comprehend the science and make up your own definitions like any other PSEUDOSCIENCE CRACKPOT
http://sci-ence.o...-flags2/

Nov 08, 2014
multiple steps
Im unsure where to put the emergence of 'consciousness' and 'humanity'... (animals 'love their children too')
when gesture crossed the fixative of reference and pointing emerged ,
by sign and vocalization linkage that increased preverbal communication efficiency by orders of magnitude .
by evolving morphemes to expand the number of calls into vocalization
by naming , a category division of the general 'perceptual associations' of ground and air threat (heads up , heads down) to snake , tiger , eagle , and leopard . ie. 'conceptualization'
teaching and social memorization , a high effort construct of shared logic between communicators.
discovering boolean , predicate , and propositional logic and creating the words that implement language
(climbing Chomskys Hierarchy ). [which raises the question of philogical computational classification]

just a few steps that come to mind

Nov 08, 2014
I apologize for the last line , narcissism and self glorification

Nov 09, 2014
@Captain Stumpy: Yes, that discovery.

And thanks for the consolation!

JVK
Nov 09, 2014
Role of olfaction in Octopus vulgaris reproduction http://www.scienc...14004006
reported as: http://blogs.scie...s-heart/

cites in context: "Future work on O. vulgaris olfaction must also consider how animals acquire the odours detected by the olfactory organ and what kind of odour the olfactory organ perceives. The OL acting as control centre may be target organ for metabolic hormones such as leptin like and insulin like peptides, and olfactory organ could exert regulatory action on the OL via epigenetic effects of nutrients and pheromones on gene expression (Kohl, 2013; Elekonich and Robinson, 2000).

Kohl, 2013 is an extension our 1996 review of RNA-mediated cell type differentiation that Elekonich and Robinson, 2000 extended from microbes and mammals to invertebrates.
http://www.ncbi.n...24693353 Nutrient-dependent/pheromone-controlled...

Nov 14, 2014
not only do animals love -> their <- children , some of them will even adopt humans

history is replete with examples of human conquest , infanticide , and forced breeding

who is boko haram for $200 alex

JVK
Nov 14, 2014
Video: How to anesthetize an octopus
http://news.scien...s_thread

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