Bipedal locomotion in zoo apes: Revisiting the hylobatian model for
bipedal origins

Abstract

Bipedal locomotion is a hallmark of being human. Yet the body form
from which bipedalism evolved remains unclear. Specifically, the
positional behaviour (i.e. orthograde vs. pronograde) and the length
of the lumbar spine (i.e. long and mobile vs. short and stiff) of the
last common ancestor (LCA) of the African great apes and humans
require further investigation. While fossil evidence would be the most
conclusive, the paucity of hominid fossils from 5–10 million years ago
makes this field of research challenging. In their absence, extant
primate anatomy and behaviour may offer some insight into the
ancestral body form from which bipedalism could most easily evolve.
Here, we quantify the frequency of bipedalism in a large sample (N =
496) of zoo-housed hominoids and cercopithecines. Our results show
that while each studied species of ape and monkey can move bipedally,
hylobatids are significantly more bipedal and engage in bipedal
locomotion more frequently and for greater distances than any other
primate sampled. These data support hypotheses of an orthograde,
long-backed and arboreal LCA, which is consistent with hominoid
fossils from the middle-to-late Miocene. If true, knuckle-walking
evolved in parallel in Pan and Gorilla, and the human body form,
particularly the long lower back and orthograde posture, is conserved.

Open access: https://doi.org/10.1017/ehs.2022.9

Most bipedal, least aquatic?

Pandora wrote:

> Bipedal locomotion is a hallmark of being human. Yet the body form
> from which bipedalism evolved remains unclear. Specifically, the
> positional behaviour (i.e. orthograde vs. pronograde) and the length
> of the lumbar spine (i.e. long and mobile vs. short and stiff) of the
> last common ancestor (LCA) of the African great apes and humans
> require further investigation. While fossil evidence would be the most
> conclusive, the paucity of hominid fossils from 5–10 million years ago
> makes this field of research challenging. In their absence, extant
> primate anatomy and

This is what "Gets" me.

Why is it missing?

The most obvious answer is: They're looking in the wrong place.

So what's the right place?

Well first and foremost is Asia. Listen to the good Doctor. Investigate
other possibilities. To NOT do that is to try and uncover the answers by
assuming that you already have the answers.

"Well we can't look for them in Asia because we know they're here, in
Africa." Okay. So if you know where the fossils are, dig them up already!

And if you don't know where the fossils are, STOP pretending that you
do and go look for the goddamn things!

Oo! You can't wrestle your grip off of Africa, right? So if they exist, this
LCA you're talking about, I can tell you exactly where they are. If they
exist in Africa.

But you already know:

Pick a date. Be it 5 million years or whatever, choose your date for this
magical LCA of yours. Next, go look in 5 million year old river deltas.
Look in 5 million year old flood plains. Look in the bends of 5 million
year old rivers.

Volcanoes! It's tricky, a lava flow is going to essentially vaporize any
animal if crosses but, there are other types of eruptions... other types
of volcanic debris. Look at Pompeii, for Christ's sake.

I don't think you'll find your LCA there but we both know that you'll
find SOMETHING, and whatever it is you're call it a human ancestor.

"It re-writes the book on human evolution," you'll exclaim.

Guaranteed.

You know, EXACTLY like every other goddamn time...

-- --

https://jtem.tumblr.com/post/712901970583846912

Bipedal locomotion in zoo apes:
Revisiting the hylobatian model for bipedal origins
Kyle H Rosen, Caroline E Jones & Jeremy M DeSilva 2022
Evol.Hum.Sci. doi org/10.1017/ehs.2022.9

Bipedal locomotion is a hallmark of being human.(& of hylobatids, kangaroos, birds etc. --mv) Yet the body form from which bipedalism evolved remains unclear.(no: google "aquarboreal" --mv) Specifically, the positional behaviour (i.e. orthograde vs. pronograde) and the length of the lumbar spine (i.e. long and mobile vs. short and stiff) of the last common ancestor (LCA) of the African great apes and humans require further investigation. While fossil evidence would be the most conclusive, the paucity of hominid fossils from 5–10 million years ago makes this field of research challenging.(paucity? Oreo-, Ourano-, Graecopith were probably hominid & aquarboreal, the Trachilos BP footprints were clearly BP: most likely late-Miocene hominids in Medit.swamp forests were BP & aquarboreal --mv) In their absence(no --mv), extant primate anatomy and behaviour may offer some insight into the ancestral body form from which bipedalism could most easily evolve.(yes, google "aquarboreal" --mv)
Here, we quantify the frequency of bipedalism in a large sample (N = 496) of zoo-housed hominoids and cercopithecines. Our results show that while each studied species of ape and monkey can move bipedally, hylobatids are significantly more bipedal and engage in bipedal locomotion more frequently and for greater distances than any other primate sampled.(yes, see our Med.Hypoth. & Hum.Evol.papers --mv) These data support hypotheses of an orthograde, long-backed(?? apes have less lumbar vertebrae than OWMs --mv) and arboreal LCA, which is consistent with hominoid fossils from the middle-to-late Miocene.(of course: the hominoid LCA was already BP & aquarboreal --mv) If true, knuckle-walking evolved in parallel in Pan and Gorilla, and the human body form, particularly the long lower back(no: 5 lumbar vertebrae, 7 in cercopiths --mv) and orthograde posture, is conserved.(I was one of the first to hypothesize parallel evolution of KWing in Pan//Gorilla, Med.Hypoth.16:17-32,1985 & Hum.Evol.9:121-139,1994 --mv)

IOW, not revisiting but confirming our view: Mio-Pliocene Hominoidea were already BP in coastal & swamp forests: wading upright + climbing arms overhead in the branches above the water, google "aquarboreal".
This also implies that BP australopiths were related to Gorilla or Pan (E & S.Afr.apiths resp.), e.g. Hum.Evol.9:121-139,1994 & Hum.Evol.11:35-41,1996, rather than to Homo: Pliocene Homo was on his way to Java (Mojokerto early-Pleistocene), e.g. see my book p.299-300, google "GondwanaTalks Verhaegen".

JTEM is so reasonable wrote:
> Pandora wrote:
>
>> Bipedal locomotion is a hallmark of being human. Yet the body form
>> from which bipedalism evolved remains unclear. Specifically, the
>> positional behaviour (i.e. orthograde vs. pronograde) and the length
>> of the lumbar spine (i.e. long and mobile vs. short and stiff) of the
>> last common ancestor (LCA) of the African great apes and humans
>> require further investigation. While fossil evidence would be the most
>> conclusive, the paucity of hominid fossils from 5–10 million years ago
>> makes this field of research challenging. In their absence, extant
>> primate anatomy and
>
> This is what "Gets" me.
>
> Why is it missing?
>
> The most obvious answer is: They're looking in the wrong place.
>
> So what's the right place?
>
> Well first and foremost is Asia. Listen to the good Doctor. Investigate

What's he a doctor in? LOL

Primum Sapienti wrote:

> JTEM is so reasonable wrote:
> > Pandora wrote:
> >
> >> Bipedal locomotion is a hallmark of being human. Yet the body form
> >> from which bipedalism evolved remains unclear. Specifically, the
> >> positional behaviour (i.e. orthograde vs. pronograde) and the length
> >> of the lumbar spine (i.e. long and mobile vs. short and stiff) of the
> >> last common ancestor (LCA) of the African great apes and humans
> >> require further investigation. While fossil evidence would be the most
> >> conclusive, the paucity of hominid fossils from 5–10 million years ago
> >> makes this field of research challenging. In their absence, extant
> >> primate anatomy and
> >
> > This is what "Gets" me.
> >
> > Why is it missing?
> >
> > The most obvious answer is: They're looking in the wrong place.
> >
> > So what's the right place?
> >
> > Well first and foremost is Asia. Listen to the good Doctor. Investigate

> What's he a doctor in? LOL

What answer *Magically* transforms the total lack of fossils into an
abundance?

What answer makes your bullshit "Cite" truthful & accurate?

Have you any grasp of the topic at all? Any?

-- --

https://jtem.tumblr.com/post/713876271508193280

JTEM is so reasonable wrote:
> Primum Sapienti wrote:
>
>> JTEM is so reasonable wrote:
>>> Pandora wrote:
>>>
>>>> Bipedal locomotion is a hallmark of being human. Yet the body form
>>>> from which bipedalism evolved remains unclear. Specifically, the
>>>> positional behaviour (i.e. orthograde vs. pronograde) and the length
>>>> of the lumbar spine (i.e. long and mobile vs. short and stiff) of the
>>>> last common ancestor (LCA) of the African great apes and humans
>>>> require further investigation. While fossil evidence would be the most
>>>> conclusive, the paucity of hominid fossils from 5–10 million years ago
>>>> makes this field of research challenging. In their absence, extant
>>>> primate anatomy and
>>>
>>> This is what "Gets" me.
>>>
>>> Why is it missing?
>>>
>>> The most obvious answer is: They're looking in the wrong place.
>>>
>>> So what's the right place?
>>>
>>> Well first and foremost is Asia. Listen to the good Doctor. Investigate
>
>> What's he a doctor in? LOL
>
> What answer *Magically* transforms the total lack of fossils into an
> abundance?

Can't answer the question I see.

> What answer makes your bullshit "Cite" truthful & accurate?
>
> Have you any grasp of the topic at all? Any?

Primum Sapienti wrote:

> Can't

I get it, you're a bot. There's no intelligence behind you, A.I. or
otherwise. But...

> Bipedal locomotion is a hallmark of being human.

No it isn't. This is wrong. It's stupid. Bipedal locomotion goes
back at least what, 7 million years? Probably a great deal
longer than that, especially if teeth are "Evidence."

Officially Homo, humans, don't go back even half that far. So
our genus is a relative newcomer to bipedalism. Most of the
history of bipedalism has been occupied by non-humans.

This makes a difference. It's a filter. It's putting a fence around
your thinking, which was clearly flawed even before you made
the mistake of posting this.

-- --

https://jtem.tumblr.com/post/716268653482524672

Op woensdag 3 mei 2023 om 06:29:07 UTC+2 schreef JTEM is so reasonable:
....
kudu runner:
> > Bipedal locomotion is a hallmark of being human.

:-D
Some of these fools will never understand, JTEM.
Early-Miocene hominoids were already BP: google "aquarboreal".
Humans & hylobatids (still?again) are BP.

> No it isn't. This is wrong. It's stupid. Bipedal locomotion goes
> back at least what, 7 million years? Probably a great deal
> longer than that, especially if teeth are "Evidence."
> Officially Homo, humans, don't go back even half that far. So
> our genus is a relative newcomer to bipedalism. Most of the
> history of bipedalism has been occupied by non-humans.
> This makes a difference. It's a filter. It's putting a fence around
> your thinking, which was clearly flawed even before you made
> the mistake of posting this.