South African skeleton shows humans learned to walk upright in the trees

December 10, 2018, University of Liverpool
South African skeleton shows humans learned to walk upright in the trees
Credit: University of Liverpool

The analysis of the world's most complete skeleton of an early human ancestor, conducted by a research collaboration involving the University of Liverpool, offers conclusive evidence that human ancestors became efficient upright walkers while they were still substantially tree dwelling animals.

The first bones of the 3.67 million old skeleton, specimen StW 573 nicknamed 'Little Foot', were 12 foot bones and leg bone fragments identified in boxes in the 1990s. The rest of the skeleton has undergone two decades of painstaking excavation, cleaning, restoring and analysis. It was found in a very deep cavern, with the bone embedded in a concrete-like matrix. The bone is very delicate and in some cases literally paper-thin. However, it has given scientists a far greater understanding of how our species evolved.

Limbs intact

The over 90 percent complete skeleton of an old female, much more than twice as complete as the famous Lucy, and considerably older as well, Little Foot is a member of the genus Australopithecus, a widespread and varied genus of hominins to which Lucy belonged, and which was an early precursor to modern-day Homo sapiens which appeared roughly 300,000 years ago. Little Foot is the first fossil of Australopithecus ever to have been discovered with its limbs intact.

The studies support the argument of her discoverer, Professor Ronald Clarke of the University of the Witwatersrand, that there were two species of Australopithecus living at the same time in South Africa's 'Cradle of Humankind', Australopithecus africanus, which was small, like Lucy, and probably primarily tree-dwelling, and Australopithecus prometheus, which was probably just within the range of modern human stature.

Important finding

As part of the study, which has been reported in Nature Science, Professor Robin Crompton, Honorary University of Liverpool Research Associate in Musculoskeletal Biology, and his colleagues analysed how she would have walked.

Professor Crompton, states: "This hominin, for the first time in the fossil record, had longer lower limbs than upper limbs, like ourselves. This is an important finding, as the slightly older hominin Ardipithecus, which came before Australopithecus, had longer arms than legs – more like other great apes such as the gorilla.

"That means she was being selected for long stride length in bipedalism. Moreover, unlike Lucy, 'Littlefoot' had a hip joint like our own, able to transmit large forces from the trunk to the leg and vice versa. Although Little Foot's legs were longer than her arms, they had not yet achieved the great relative leg length found in humans. Thus, she would not have been as good at carrying objects as we are. However, she would have been much better at climbing trees than modern humans.

"It is most likely that she would have resided in an area that was a mix of tropical rainforest, broken woodland and grassland, through which she would roam around. She would have lived primarily on forest fruits and leaves"

The study involved collaborators from; Aintree University NHS Trust's Department of Rheumatology, University of Brighton's School of Health Sciences, University of Birmingham's School of Biosciences, University of Manchester's School of Earth and Environmental Science, Birmingham-Southern College's Department of Biology (Alabama, U.S.A.) and University of the Witwatersrand's Evolutionary Studies Institute (Johannesburg, South Africa).

The paper is titled "Functional Anatomy, Biomechanical Performance Capabilities and Potential Niche of StW 573: an Australopithecus Skeleton (circa 3.67 Ma) From Sterkfontein Member 2, and its significance for The Last Common Ancestor of the African Apes and for Hominin Origins."

Explore further: Cranium of a four-million-year-old hominin shows similarities to that of modern humans

More information: Robin Huw Crompton et al. Functional Anatomy, Biomechanical Performance Capabilities and Potential Niche of StW 573: an Australopithecus Skeleton (circa 3.67 Ma) From Sterkfontein Member 2, and its significance for The Last Common Ancestor of the African Apes and for Hominin Origins, Nature Science (2018). DOI: 10.1101/481556

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RobertKarlStonjek
not rated yet Dec 10, 2018
Bonobos walk upright around 40% of the time. They can carry weight and manipulate things with their hands whilst walking, so hominids in the human lineage were far from the first to do this, assuming that Bonobos existed back then.
FredJose
1 / 5 (7) Dec 11, 2018
offers conclusive evidence that human ancestors became efficient upright walkers while they were still substantially tree dwelling animals

There is nothing conclusive about this at all - evolution NEVER happened, except in the minds of those who want to see it that way.
We all have the same evidence, we just choose to interpret it differently according to our own worldviews which in this particular case in the article happens to be the godless , evolutionary worldview in which everything made itself.
One reason the study cannot be conclusive is that it neglects to answer the question as to how, where and why the creatures actually had leg bones, sinew and muscles with a nerve system connection to a brain that controlled its actions. Where did that all come from? There is no definite, cogent answer in the evolutionary worldview, only lots of hand waving and an appeal to great faith in time.
Da Schneib
4.9 / 5 (8) Dec 11, 2018
@FreddyJoe blurts, from its trailer park,
evolution NEVER happened
It's happening now, @FreddyJoe. Right now today, and we have observed it. This isn't cutting edge, it's well accepted fact with lots of examples, from moths that evolved to match the bark of soot-coated trees around London, to the Central European blackcap warbler changing its wing shape and bill shape to migrate to Britain and get goodies from backyard bird feeders instead of Spain to raid the fruit trees, to bacteria evolving antibiotic resistance.

This is just stupid. You might as well insist that there aren't any stars in the sky, or there's no such thing as air.
SCVGoodToGo
5 / 5 (7) Dec 11, 2018
If ignorance is bliss, Fred must be the happiest 'man' on Earth.
torbjorn_b_g_larsson
4.2 / 5 (5) Dec 11, 2018
evolution NEVER happened


Trolling uselessly, since the article describes precisely observed evolution and we can all read it:

"... offers conclusive evidence that human ancestors became efficient upright walkers while they were still substantially tree dwelling animals ... an early precursor to modern-day Homo sapiens ... was being selected for long stride length ... significance for The Last Common Ancestor of the African Apes and for Hominin Origins ...".

If you are not interested in - or distraught by - known or newfound facts, don't comment at all; readers are definitely not interested in trolling.
Crvm737
5 / 5 (1) Dec 11, 2018
Bonobos walk upright around 40% of the time. They can carry weight and manipulate things with their hands whilst walking, so hominids in the human lineage were far from the first to do this, assuming that Bonobos existed back then.


The problem with your hypothesis is that the Chimpanzee split took place long after our split of common ancestor with Chimpanzees. So they aren't around back then but neither were we. The species of common ancestor for both lineages is extinct.
Da Schneib
not rated yet Dec 12, 2018
Bonobos walk upright around 40% of the time. They can carry weight and manipulate things with their hands whilst walking, so hominids in the human lineage were far from the first to do this, assuming that Bonobos existed back then.


The problem with your hypothesis is that the Chimpanzee split took place long after our split of common ancestor with Chimpanzees. So they aren't around back then but neither were we. The species of common ancestor for both lineages is extinct.
Around, oh say, 10 million years ago. Both lineages have evolved since then along different lines.

Modern humans are actually closer to ardipithecus and australopithecus than to pan (chimps), but both of them are extinct too.
Da Schneib
not rated yet Dec 12, 2018
Australopithecines could walk competently on two feet. "Competently" means they could run on two feet, though perhaps not as fast as anatomically modern humans (they couldn't win a marathon, and might not be able to finish it).
marc verhaegen
not rated yet Dec 13, 2018
Fantastic fossil, but in no way it "shows humans learned to walk upright in the trees".
Ostriches have rel.shorter legs & more horizontal spines than wading herons & flamingoes.
Australopiths often lived in swamp forests & wetlands (perhaps only seasonally), see e.g. K.Reed 1997 JHE 32:289.
Extant great apes also regularly or occasionally still spend some time in forest swamps, google e.g. "bonobo wading" &"gorilla bai".
Apparently, Little Foot (Au.prometheus) was one of the many orthograde(vertical) aquarboreal australopiths, some probably spent more time in the branches (arm-hanging cf curved phalanges), other spent more time in the swamps (wading cf longer legs), see our 2002 TREE paper (Verhaegen, Puech & Munro "Aquarboreal Ancestors?" Trends Ecol.Evol.17:212-217).
Human locomotion (cursorial bipedalism) is IMO a late-Pleistocene derivation from this ancient common-hominid orthograde aquarborealism, google e.g"Ape and Human Evolution 2018 biology vs anthropocentrism".

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