On Saturday, March 26, 2022 at 4:32:48 PM UTC-4, Paul Crowley wrote:
> On Saturday 26 March 2022 at 02:46:58 UTC, DD'eDeN aka note/nickname/alas_my_loves wrote:
>
> >> Which of the following is more parsimonious?
> >>..
> >> A) A taxon split, into X and Y.
> >> Both X and Y changed their forms drastically
> >> finding new roles (or allied sets of niches) in the
> >> forest -- abandoning their former niches.
> >.
> > More likely their niches abandoned them due to climate change or other externality.
> Essentially nonsense. Gibbons have been around
> for 20+ Myr. Large apes: chimps/gorillas/orangs
> for 10+
Genetically.
> >> B) A taxon split, into X and Y.
> >> X was the old taxon, and stayed pretty much the
> >> same, occupying the same set of long-established
> >> niches; Y was new, and radically different -- as
> >> the result of finding and occupying a wholly new
> >> niche (or set of niches)
> >.
> > Less likely unless the diverging populations were separated in
> > 2 different locations (or as in Homo, a new ground shelter evolved).
> Separation for a few 100 K years (or even
> a million) is common. See Bonobos --
> presumably the Congo river changed its
> course. In this case both populations
> continued (more-or-less) in their ancient
> niches.
Rivers change courses. Climate changes niches.

> > See scapula position in tarsiers, lemurs, tupaia vs baboons.
> You'd need to study live animals to see
> where their scapulae are located. but
> these animals are so small, that their
> location is almost irrelevant.
Really? Bats?
Tarsiers
> weigh around 100 grams -- half an apple or
> two medium eggs. Tupaia are only slightly
> larger. These are tiny, nearly mouse-sized.
> Size matters. Muscle power and bone
> strength scale more than proportionately.
Mice have bigger brains than blue whales proportionately.
>
> That's highly relevant when a taxon with
> a new body form comes into existence.
> Smaller animals can afford much more
> plasticity.
Yey mice mostly stay the same size and shape.

Modern small gibbons weigh
> ~5 kg. The very first ones were probably
> less than half that.

??

A monkey of that size
> could brachiate to some extent --

??

much
> better than one double its size with the
> same anatomy.

?!

If the circumstances
> favoured more of that activity, the small
> monkey could readily specialise in it.

How many do? None.

> >>> but the common ancestor had a skeletal frame midway
> >>> between them, very typical of nonspecialized arboreal-terrestrial taxa.
> >>..
> >> A childish conception of evolution. It's like
> >> claiming that hominins and chimps had an
> >> ancestor that was equally adept (and equally
> >> clumsy) at both bipedal and quadrupedal
> >> running & walking.
> >..
> > Nope, entirely wrong. Upright bipedal habit allows scapula to shift,
> Firstly, we're talking about chests,

Then why'd you bring up scapulae?

> and the bones and ligaments around
> them. Bipedalism is primarily about
> legs and the pelvis.

??

Secondly, it's
> about evolutionary developments
> before 20 ma when there were no
> bipeds.
>
??

> If you were right, you should be able to
> refer to numerous primate (& other?)
> species (> ~2kg) which have scapula in
> the gibbon/hominoid position -- on
> their backs. Let's see the list.
>
What drugs are you on?

> Hominoid chests became shallow and
> broad so that the spinal column could
> be central. That was to enable fast
> brachiation.

Wrong. First upright climbing and slow brachiation.

Find other mammals >~2kg
> with shallow, broad chests.

Why?

> > palmigrade pronograde quadrupedalism forbids shift, ape knucklewalking
> > allows the shift.
> Nonsense on every level. K/walking is
> quadrupedal, with a horizontal trunk.

You snipped too much. What are you responding to?

On Sunday 27 March 2022 at 03:14:08 UTC+1, DD'eDeN aka note/nickname/alas_my_loves wrote:

>>> More likely their niches abandoned them due to climate change or other externality.
>>...
>> Essentially nonsense. Gibbons have been around
>> for 20+ Myr. Large apes: chimps/gorillas/orangs
>> for 10+
> ..
> Genetically.

Do you think each taxon now occupies quite
different niches from (say) 10 ma, while
retaining their genetic inheritance?

>> Separation for a few 100 K years (or even
>> a million) is common. See Bonobos --
>> presumably the Congo river changed its
>> course. In this case both populations
>> continued (more-or-less) in their ancient
>> niches.
>..
> Rivers change courses. Climate changes niches.

The climate has been extremely variable
for the past 1-1.5 myr --- with ice-ages and
interglacials. Yet there seems to be no
change whatever in either the chimp or
the bonobo niches.

>>> See scapula position in tarsiers, lemurs, tupaia vs baboons.
>>..
>> You'd need to study live animals to see
>> where their scapulae are located. but
>> these animals are so small, that their
>> location is almost irrelevant.
>..
> Really? Bats?

The physical demands placed by flight
on bats and birds are so great that each
have to be 'precisely engineered'. That
does not apply to much more generalist
ground-living (or tree-living) mammals.

>> Tarsiers
>> weigh around 100 grams -- half an apple or
>> two medium eggs. Tupaia are only slightly
>> larger. These are tiny, nearly mouse-sized.
>> Size matters. Muscle power and bone
>> strength scale more than proportionately.
>..
> Mice have bigger brains than blue whales proportionately.
>..
>> That's highly relevant when a taxon with
>> a new body form comes into existence.
>> Smaller animals can afford much more
>> plasticity.
>..
> Yey mice mostly stay the same size and shape.

Mice species come and go with great
rapidity, but the body form remains
much the same. I am talking about NEW
body forms -- particularly that of gibbons/
hominoids.

>> Modern small gibbons weigh
>> ~5 kg. The very first ones were probably
>> less than half that.
>..
> ??

As I said, we need a lot of plasticity
here. You don't get that in big, slow-
reproducing animals.

>> A monkey of that size could brachiate to some extent --
>..
> ??

What's the problem? If there's a long
thin horizontal branch with fruit at the
end of it, the small proto-gibbon
monkey brachiates along it and gets
the fruit, faster and more effectively
than a non-brachiating monkey.

>> much
>> better than one double its size with the
>> same anatomy.
>..
> ?!

One double the size has much greater
problems acquiring such skills. Ever
notice how small Olympic gymnasts
usually are?

>> If the circumstances
>> favoured more of that activity, the small
>> monkey could readily specialise in it.
>..
> How many do? None.

Modern gibbons are already quite
small. They leave not enough room
for even smaller ones,

>>>> It's like
>>>> claiming that hominins and chimps had an
>>>> ancestor that was equally adept (and equally
>>>> clumsy) at both bipedal and quadrupedal
>>>> running & walking.
>>>..
>>> Nope, entirely wrong. Upright bipedal habit allows scapula to shift,
>>..
>> Firstly, we're talking about chests,
> ..
> Then why'd you bring up scapulae?

See the next line -- the bones and ligaments
around the chest (i.e. incl. scapulae).

>> and the bones and ligaments around
>> them.

>> Bipedalism is primarily about
>> legs and the pelvis.
> ..
> ??

What's your problem? It would not
be too difficult to portray a bipedal
baboon, with the standard chest
(narrow and deep) but with almost-
human legs and pelvises

>> If you were right, you should be able to
>> refer to numerous primate (& other?)
>> species (> ~2kg) which have scapula in
>> the gibbon/hominoid position -- on
>> their backs. Let's see the list.
>..
> What drugs are you on?

What's your problem? You claim that
scapulae can readily move from the
side (as in monkeys, etc.) to the back
(as in gibbons/hominoids). So why
doesn't it happen? Why can't you
quote examples?

>> Hominoid chests became shallow and
>> broad so that the spinal column could
>> be central. That was to enable fast
>> brachiation.
> ..
> Wrong. First upright climbing and slow brachiation.

I know that this is your 'opinion'. God
alone knows how you arrived at it. It's
based on nothing. It's contrary to all
available evidence.

>> Find other mammals >~2kg with shallow, broad chests.
> ..
> Why?

You claim that they exist -- or should exist.
All you need are animals (incl primates)
that climb trees (when upright) and do
a bit of brachiation.

>>> palmigrade pronograde quadrupedalism forbids shift, ape knucklewalking
>>> allows the shift.
>>..
>> Nonsense on every level. K/walking is
>> quadrupedal, with a horizontal trunk.
> ..
> You snipped too much. What are you responding to?

You claim that palmigrade pronograde
quadrupedalism forbids the shifting of
the scapulae from the side to the back.
Whereas ape quadrupedalism allows it!

On Sunday, March 27, 2022 at 4:10:41 PM UTC-4, Paul Crowley wrote:
> On Sunday 27 March 2022 at 03:14:08 UTC+1, DD'eDeN aka note/nickname/alas_my_loves wrote:
>
> >>> More likely their niches abandoned them due to climate change or other externality.
> >>...
> >> Essentially nonsense. Gibbons have been around
> >> for 20+ Myr. Large apes: chimps/gorillas/orangs
> >> for 10+
> > ..
> > Genetically.
>
> Do you think each taxon now occupies quite
> different niches from (say) 10 ma, while
> retaining their genetic inheritance?
> >> Separation for a few 100 K years (or even
> >> a million) is common. See Bonobos --
> >> presumably the Congo river changed its
> >> course. In this case both populations
> >> continued (more-or-less) in their ancient
> >> niches.
> >..
> > Rivers change courses. Climate changes niches.
> The climate has been extremely variable
> for the past 1-1.5 myr --- with ice-ages and
> interglacials. Yet there seems to be no
> change whatever in either the chimp or
> the bonobo niches.
> >>> See scapula position in tarsiers, lemurs, tupaia vs baboons.
> >>..
> >> You'd need to study live animals to see
> >> where their scapulae are located. but
> >> these animals are so small, that their
> >> location is almost irrelevant.
> >..
> > Really? Bats?
>
> The physical demands placed by flight
> on bats and birds are so great that each
> have to be 'precisely engineered'. That
> does not apply to much more generalist
> ground-living (or tree-living) mammals.
> >> Tarsiers
> >> weigh around 100 grams -- half an apple or
> >> two medium eggs. Tupaia are only slightly
> >> larger. These are tiny, nearly mouse-sized.
> >> Size matters. Muscle power and bone
> >> strength scale more than proportionately.
> >..
> > Mice have bigger brains than blue whales proportionately.
> >..
> >> That's highly relevant when a taxon with
> >> a new body form comes into existence.
> >> Smaller animals can afford much more
> >> plasticity.
> >..
> > Yey mice mostly stay the same size and shape.
> Mice species come and go with great
> rapidity, but the body form remains
> much the same. I am talking about NEW
> body forms -- particularly that of gibbons/
> hominoids.
> >> Modern small gibbons weigh
> >> ~5 kg. The very first ones were probably
> >> less than half that.
> >..
> > ??
>
> As I said, we need a lot of plasticity
> here. You don't get that in big, slow-
> reproducing animals.
> >> A monkey of that size could brachiate to some extent --
> >..
> > ??
>
> What's the problem? If there's a long
> thin horizontal branch with fruit at the
> end of it, the small proto-gibbon
> monkey brachiates along it and gets
> the fruit, faster and more effectively
> than a non-brachiating monkey.
> >> much
> >> better than one double its size with the
> >> same anatomy.
> >..
> > ?!
>
> One double the size has much greater
> problems acquiring such skills. Ever
> notice how small Olympic gymnasts
> usually are?
> >> If the circumstances
> >> favoured more of that activity, the small
> >> monkey could readily specialise in it.
> >..
> > How many do? None.
>
> Modern gibbons are already quite
> small. They leave not enough room
> for even smaller ones,
> >>>> It's like
> >>>> claiming that hominins and chimps had an
> >>>> ancestor that was equally adept (and equally
> >>>> clumsy) at both bipedal and quadrupedal
> >>>> running & walking.
> >>>..
> >>> Nope, entirely wrong. Upright bipedal habit allows scapula to shift,
> >>..
> >> Firstly, we're talking about chests,
> > ..
> > Then why'd you bring up scapulae?
> See the next line -- the bones and ligaments
> around the chest (i.e. incl. scapulae).
> >> and the bones and ligaments around
> >> them.
>
> >> Bipedalism is primarily about
> >> legs and the pelvis.
> > ..
> > ??
>
> What's your problem? It would not
> be too difficult to portray a bipedal
> baboon, with the standard chest
> (narrow and deep) but with almost-
> human legs and pelvises
> >> If you were right, you should be able to
> >> refer to numerous primate (& other?)
> >> species (> ~2kg) which have scapula in
> >> the gibbon/hominoid position -- on
> >> their backs. Let's see the list.
> >..
> > What drugs are you on?
> What's your problem? You claim that
> scapulae can readily move from the
> side (as in monkeys, etc.) to the back
> (as in gibbons/hominoids). So why
> doesn't it happen? Why can't you
> quote examples?
> >> Hominoid chests became shallow and
> >> broad so that the spinal column could
> >> be central. That was to enable fast
> >> brachiation.
> > ..
> > Wrong. First upright climbing and slow brachiation.
> I know that this is your 'opinion'. God
> alone knows how you arrived at it. It's
> based on nothing. It's contrary to all
> available evidence.
> >> Find other mammals >~2kg with shallow, broad chests.
> > ..
> > Why?
>
> You claim that they exist -- or should exist.
> All you need are animals (incl primates)
> that climb trees (when upright) and do
> a bit of brachiation.
> >>> palmigrade pronograde quadrupedalism forbids shift, ape knucklewalking
> >>> allows the shift.
> >>..
> >> Nonsense on every level. K/walking is
> >> quadrupedal, with a horizontal trunk.
> > ..
> > You snipped too much. What are you responding to?
> You claim that palmigrade pronograde
> quadrupedalism forbids the shifting of
> the scapulae from the side to the back.
> Whereas ape quadrupedalism allows it.

Tarsiers & lemurs are proto-primates which unlike monkeys did not become dog-like running quadrupeds. They tend to posture upright, with heads swiveling on a vertical axis in orthograde fashion. This was the ancestral form of primates, not the quadrupedal baboon form. Apes moved scapulae slightly rearward, monkeys slightly sideward. Ape ancestors never had baboon-like ancestors with deep narrow chests, but did have the generalized mammalian arboreal form, slightly deeper and narrower chests than modern apes. They had inherited the upright cranial orientation from proto-primates, and this induced the habits of upright vertical climbing, upright bipedal branch walking, upright slow brachiation while monkeys went more to ground-based pronograde quadrupedalism (though all primates tend to sit upright).
Most of what you said above does not reflect my opinion.

On Monday 28 March 2022 at 10:13:04 UTC+1, DD'eDeN aka note/nickname/alas_my_loves wrote:

> Tarsiers & lemurs are proto-primates

You've no good basis for that assertion.
Tarsiers are so different from the bulk
of primates (being nocturnally active
for a start) that they're most unlikely
to be representative of anything early.
Lemurs came from tiny numbers which
rafted from Africa ~40 ma. Africa
probably had a great variety of primates
(and proto-primate hang-ons) at the
time.

> which unlike monkeys did not become dog-like running quadrupeds.

Primates generally live in trees. Dog-
running quadrupeds (i.e. baboons)
seem to have evolved around 2 ma
when there were relatively few
diurnal predators around (hominins
had got rid of most).

> They tend to posture upright, with heads swiveling on a vertical axis in
> orthograde fashion. This was the ancestral form of primates, not the
> quadrupedal baboon form.

True, but they still had the ancient
dominant mammalian body-form,
like that of terrestrial animals: narrow
and deep chests. A powerful reason
is needed to change something so
fundamental and their ancestors
never one.

> Apes moved scapulae slightly rearward, monkeys slightly sideward.

This is nonsense. Your hypothetical
midway position is impossible for an
animal that has to cope with gravity.
No extant animal >~2kg has scapulae
in that position

> Ape ancestors never had baboon-like ancestors with deep narrow chests,

All primates had ancestors with deep
narrow chests -- that's the default form
with the heart in its optimal position.
Apes changed from that -- for powerful
reasons that also involved a centralised
spine, the loss of tails and an aversion
to bodies of water.

> but did have the generalized mammalian arboreal form, slightly deeper
> and narrower chests than modern apes.

Fantasy. You've no evidence for this.

> They had inherited the upright cranial orientation from proto-primates,
> and this induced the habits of upright vertical climbing, upright bipedal
> branch walking, upright slow brachiation while monkeys went more to
> ground-based pronograde quadrupedalism (though all primates tend to
> sit upright).

Monkeys (& not apes) also sleep upright
-- usually huddled together along a
branch. That's 12 hours of the 24 being
vertical, apart from their daytime
climbing, eating, sitting and grooming.
All this 'verticality' should have the effect
you postulate on their anatomy -- on
their spines, chests and locations of their
scapulae. But it doesn't. Drastic changes
in anatomy only come about as the result
of intense selective pressure.

Vertical climbing, walking on branches
and slow brachiation do not provide the
selective pressure you imagine.

(I don't think you grasp 'selection' at all,
and you attribute all change to genes, or
randomness, or some such.)

> Most of what you said above does not reflect my opinion.

It was mostly questions that you
can't answer

On Monday, March 28, 2022 at 4:52:56 PM UTC-4, Paul Crowley wrote:
> On Monday 28 March 2022 at 10:13:04 UTC+1, DD'eDeN aka note/nickname/alas_my_loves wrote:
>
> > Tarsiers & lemurs are proto-primates
> You've no good basis for that assertion.
> Tarsiers are so different from the bulk
> of primates (being nocturnally active
> for a start) that they're most unlikely
> to be representative of anything early.
> Lemurs came from tiny numbers which
> rafted from Africa ~40 ma. Africa
> probably had a great variety of primates
> (and proto-primate hang-ons) at the
> time.
> > which unlike monkeys did not become dog-like running quadrupeds.
> Primates generally live in trees. Dog-
> running quadrupeds (i.e. baboons)
> seem to have evolved around 2 ma
> when there were relatively few
> diurnal predators around (hominins
> had got rid of most).
> > They tend to posture upright, with heads swiveling on a vertical axis in
> > orthograde fashion. This was the ancestral form of primates, not the
> > quadrupedal baboon form.
> True, but they still had the ancient
> dominant mammalian body-form,
> like that of terrestrial animals: narrow
> and deep chests. A powerful reason
> is needed to change something so
> fundamental and their ancestors
> never one.
> > Apes moved scapulae slightly rearward, monkeys slightly sideward.
> This is nonsense. Your hypothetical
> midway position is impossible for an
> animal that has to cope with gravity.
> No extant animal >~2kg has scapulae
> in that position
> > Ape ancestors never had baboon-like ancestors with deep narrow chests,
> All primates had ancestors with deep
> narrow chests -- that's the default form
> with the heart in its optimal position.
> Apes changed from that -- for powerful
> reasons that also involved a centralised
> spine, the loss of tails and an aversion
> to bodies of water.
> > but did have the generalized mammalian arboreal form, slightly deeper
> > and narrower chests than modern apes.
> Fantasy. You've no evidence for this.
> > They had inherited the upright cranial orientation from proto-primates,
> > and this induced the habits of upright vertical climbing, upright bipedal
> > branch walking, upright slow brachiation while monkeys went more to
> > ground-based pronograde quadrupedalism (though all primates tend to
> > sit upright).
> Monkeys (& not apes) also sleep upright
> -- usually huddled together along a
> branch. That's 12 hours of the 24 being
> vertical, apart from their daytime
> climbing, eating, sitting and grooming.
> All this 'verticality' should have the effect
> you postulate on their anatomy -- on
> their spines, chests and locations of their
> scapulae. But it doesn't. Drastic changes
> in anatomy only come about as the result
> of intense selective pressure.
>
> Vertical climbing, walking on branches
> and slow brachiation do not provide the
> selective pressure you imagine.
>
> (I don't think you grasp 'selection' at all,
> and you attribute all change to genes, or
> randomness, or some such.)
> > Most of what you said above does not reflect my opinion.
> It was mostly questions that you
> can't answer

If you are being pedantic, lemurs and tarsiers aren't proto-primates but prosimians, since are extant, but they retain traits the primates evolved from.

prosimians: includes all of the lemurs, lorises, and related "primitive" primates.

https://youtu.be/iTe9rhLC2XE

[...]

We're going to the zoo, zoo, zoo.
How about you, you, you.
You can come too, too, too.
We're going to the zoo, zoo, zoo.

See all the monkeys scritch, scritch scratching.
Hanging by their long tails scritch, scritch scratching.
Jumping all around and scritch, scritch scratching.
We can stay all day!

We're going to the zoo, zoo, zoo.
How about you, you, you.
You can come too, too, too.
We're going to the zoo, zoo, zoo.

Yes on this version you have to get a little into the song
before reaching the primate locomotion. Or scratching.

-- --

https://jtem.tumblr.com/post/680033542752829440