John Hawks on twitter (31 May)
#Homonaledi has a small opening to the ear canal compared to
other hominins, and the DH3 skull is one of the best examples.
Why this varies is a puzzle. It is not a function of small body size,
most Australopithecus skulls have big ear openings.
Picture:
pic.twitter.com/H8JvYlfinE
(searchable on Google)

My theory:
Other things being equal, small ear openings
are probably better -- keeping out insects,
mites, and other sources of infection.

BUT if the animal is exposed to drenching down-
pours (usually of rain), or if it goes swimming,
water is likely to enter the ear canal, and cause
deafness. It may be temporary (for hours or days)
but it's greatly disabling. A larger ear canal will
allow the water to escape, and restore hearing
more quickly.

H.naledi occupied caves -- probably as a salt-
miner. It never needed to swim, and when it
rained, H.naledi stayed safe and dry.

Op zaterdag 12 juni 2021 om 13:42:23 UTC+2 schreef Paul Crowley:
> John Hawks on twitter (31 May)
> #Homonaledi has a small opening to the ear canal compared to
> other hominins, and the DH3 skull is one of the best examples.
> Why this varies is a puzzle. It is not a function of small body size,
> most Australopithecus skulls have big ear openings.
> Picture:
> pic.twitter.com/H8JvYlfinE
> (searchable on Google) >
> My theory:
> Other things being equal, small ear openings
> are probably better -- keeping out insects,
> mites, and other sources of infection. >
> BUT if the animal is exposed to drenching down-
> pours (usually of rain), or if it goes swimming,
> water is likely to enter the ear canal, and cause
> deafness. It may be temporary (for hours or days)
> but it's greatly disabling. A larger ear canal will
> allow the water to escape, and restore hearing
> more quickly. >
> H.naledi occupied caves -- probably as a salt-
> miner. It never needed to swim, and when it
> rained, H.naledi stayed safe and dry.

Where are H.sapiens & the African & even Asian apes in the figure??

On Saturday, June 12, 2021 at 7:42:23 AM UTC-4, Paul Crowley wrote:
> John Hawks on twitter (31 May)
> #Homonaledi has a small opening to the ear canal compared to
> other hominins, and the DH3 skull is one of the best examples.
> Why this varies is a puzzle. It is not a function of small body size,
> most Australopithecus skulls have big ear openings.
> Picture:
> pic.twitter.com/H8JvYlfinE
> (searchable on Google)
>
> My theory:
> Other things being equal, small ear openings
> are probably better -- keeping out insects,
> mites, and other sources of infection.
>
> BUT if the animal is exposed to drenching down-
> pours (usually of rain), or if it goes swimming,
> water is likely to enter the ear canal, and cause
> deafness. It may be temporary (for hours or days)
> but it's greatly disabling. A larger ear canal will
> allow the water to escape, and restore hearing
> more quickly.
>
> H.naledi occupied caves -- probably as a salt-
> miner. It never needed to swim, and when it
> rained, H.naledi stayed safe and dry.

I can't opine about salt mining, no idea. But long-term cave dwelling would seem to select *for* sound amplification and vision loss, unless torches were used. I guess cave bats have large ear canals.

Op zaterdag 12 juni 2021 om 13:42:23 UTC+2 schreef Paul Crowley:
> John Hawks on twitter (31 May)
> #Homonaledi has a small opening to the ear canal compared to
> other hominins, and the DH3 skull is one of the best examples.
> Why this varies is a puzzle. It is not a function of small body size,
> most Australopithecus skulls have big ear openings.
> Picture:
> pic.twitter.com/H8JvYlfinE
> (searchable on Google)

"The Aquatic Ape Theory and some common diseases"
Medical Hypotheses 24:293-300, 1987
.... Human ear-wax, consisting of impacted cerumen and skin scales, can completely occlude the ear canal, especially during showering or swimming, when the ear-wax absorbs water and swells, and even can hinder hearing. In whales, the ear canal is completely occluded by a string of connective tissue, by scaling epidermal cells, or by a horny wax plug (39): in water, an open ear canal could be the source of infections, and does not improve hearing since the sound waves are not transmitted through the air.

IOW, no wonder apith-ape ear openings were larger than in Homo.

Australopiths were no human ancestors, of course: this idea is ridiculous anthropocentrism.
Most likely (see my 1994 & 1996 Human Evolution papers):
-most if not all E.Afr.apiths belonged to the genus Gorilla, e.g. Lucy = fossil subgenus Praeanthropus afarensis Johanson,
-most if not all S.Afr.apiths belonged to the genus Pan, e.g. fossil subgenus Australopithecus africanus.
Apparently, E& S.Afr.apiths evolved in parallel from "gracile" Plio- to "robust" Pleistocene.

On Saturday 12 June 2021 at 16:04:38 UTC+1, littor...@gmail.com wrote:
> Op zaterdag 12 juni 2021 om 13:42:23 UTC+2 schreef Paul Crowley:
> > John Hawks on twitter (31 May)
> > #Homonaledi has a small opening to the ear canal compared to
> > other hominins, and the DH3 skull is one of the best examples.
> > Why this varies is a puzzle. It is not a function of small body size,
> > most Australopithecus skulls have big ear openings.
> > Picture:
> > pic.twitter.com/H8JvYlfinE
> > (searchable on Google) >
> > My theory:
> > Other things being equal, small ear openings
> > are probably better -- keeping out insects,
> > mites, and other sources of infection. >
> > BUT if the animal is exposed to drenching down-
> > pours (usually of rain), or if it goes swimming,
> > water is likely to enter the ear canal, and cause
> > deafness. It may be temporary (for hours or days)
> > but it's greatly disabling. A larger ear canal will
> > allow the water to escape, and restore hearing
> > more quickly. >
> > H.naledi occupied caves -- probably as a salt-
> > miner. It never needed to swim, and when it
> > rained, H.naledi stayed safe and dry.
>
> Where are H.sapiens & the African & even Asian apes in the figure??

Presumably it's all from some current research on
which Hawks, Berger and others are working.

All I can find is:
https://www.pnas.org/content/suppl/2004/06/21/0403595101.DC1/03595SuppText.pdf

Modelling of the “Human-Like” Chimpanzee and the “Chimpanzee-Like”
Modern Human Individuals. Relative to modern humans, chimpanzees
arecharacterized by (i) larger values in tympanic membrane area, functional
length of themalleus, and length of the external auditory canal (6), and (ii)
smaller values in stapesfootplate area, functional length of the incus (6), and
mass of the malleus–incuscomplex (7). Although there are no published data on
the cross-sectional area of theexternal auditory canal (AEAC) in chimpanzees,
the available information on the cross-sectional area of the external auditory
meatus (which is not the same measurement asour AEAC) suggests that the
external auditory canal is wider in modern humans than inchimpanzees (8). Our
measurements of AEAC on a Medieval modern human sample(range 27.8–56.7 mm2) also suggest that this area is greater in modern humans than
inchimpanzees (20.4 mm2 in the chimpanzee we have measured through 3D
CTreconstruction).

On Saturday 12 June 2021 at 18:08:46 UTC+1, DD'eDeN aka note/nickname/alas_my_loves wrote:
> > H.naledi occupied caves -- probably as a salt-
> > miner. It never needed to swim, and when it
> > rained, H.naledi stayed safe and dry.
>
> I can't opine about salt mining, no idea. But long-term cave
> dwelling would seem to select *for* sound amplification and
> vision loss, unless torches were used.

Torches were used. Their fossils are found deep
within the caves, where there is absolutely no
natural light. That would have meant foraging
(or trading) for the necessary torch materials.

> I guess cave bats have large ear canals.

Bats hate rain. That's been put down to the
energy drain (on fur that never evolved to get
wet). But it may also impede their hearing
(& echo-sounding).

On Saturday 12 June 2021 at 19:00:32 UTC+1, littor...@gmail.com wrote:
> Op zaterdag 12 juni 2021 om 13:42:23 UTC+2 schreef Paul Crowley:
> > John Hawks on twitter (31 May)
> > #Homonaledi has a small opening to the ear canal compared to
> > other hominins, and the DH3 skull is one of the best examples.
> > Why this varies is a puzzle. It is not a function of small body size,
> > most Australopithecus skulls have big ear openings.
> > Picture:
> > pic.twitter.com/H8JvYlfinE
> > (searchable on Google)
> "The Aquatic Ape Theory and some common diseases"
> Medical Hypotheses 24:293-300, 1987
> ... Human ear-wax, consisting of impacted cerumen and skin scales, can completely occlude the ear canal, especially during showering or swimming, when the ear-wax absorbs water and swells, and even can hinder hearing. In whales, the ear canal is completely occluded by a string of connective tissue, by scaling epidermal cells, or by a horny wax plug (39): in water, an open ear canal could be the source of infections, and does not improve hearing since the sound waves are not transmitted through the air.
>
> IOW, no wonder apith-ape ear openings were larger than in Homo.

I don't follow your logic here. (Rarely expect to
do so anywhere!)

As I see it australopiths (more-or-less human
ancestors) swam more than modern humans,
or did so more often in survival-critical
circumstances. They also were less
protected from tropical down-pours than
are recent humans, all resulting in the need
for good drainage from their ears -- meaning
larger canals.

Op zaterdag 12 juni 2021 om 21:50:33 UTC+2 schreef Paul Crowley:

> > > #Homonaledi has a small opening to the ear canal compared to
> > > other hominins, and the DH3 skull is one of the best examples.
> > > Why this varies is a puzzle. It is not a function of small body size,
> > > most Australopithecus skulls have big ear openings.
> > > pic.twitter.com/H8JvYlfinE

> > "The Aquatic Ape Theory and some common diseases"
> > Medical Hypotheses 24:293-300, 1987
> > ... Human ear-wax, consisting of impacted cerumen and skin scales, can completely occlude the ear canal, especially during showering or swimming, when the ear-wax absorbs water and swells, and even can hinder hearing. In whales, the ear canal is completely occluded by a string of connective tissue, by scaling epidermal cells, or by a horny wax plug (39): in water, an open ear canal could be the source of infections, and does not improve hearing since the sound waves are not transmitted through the air.
> > IOW, no wonder apith-ape ear openings were larger than in Homo.

> I don't follow your logic here.

Yes, you have no logic.
Early-Pleistocene Homo's littoral phase has 0 to do with apiths or apes.
Google "ape human evolution made easy verhaegen"

On Saturday, June 12, 2021 at 3:41:10 PM UTC-4, Paul Crowley wrote:
> On Saturday 12 June 2021 at 18:08:46 UTC+1, DD'eDeN aka note/nickname/alas_my_loves wrote:
> > > H.naledi occupied caves -- probably as a salt-
> > > miner. It never needed to swim, and when it
> > > rained, H.naledi stayed safe and dry.
> >
> > I can't opine about salt mining, no idea. But long-term cave
> > dwelling would seem to select *for* sound amplification and
> > vision loss, unless torches were used.
> Torches were used.

Speculation or evidenced?

Their fossils are found deep
> within the caves, where there is absolutely no
> natural light.

Light reception is not absolutely necessary, taste is absolutely necessary to harvest salt, sound reception is probably likely (group spelunking).

That would have meant foraging
> (or trading) for the necessary torch materials.

Physical evidence?

> > I guess cave bats have large ear canals.
> Bats hate rain. That's been put down to the
> energy drain (on fur that never evolved to get
> wet). But it may also impede their hearing
> (& echo-sounding).

Insects avoid flight in rain, so insectivorous bats do too.

Paul Crowley wrote:

> H.naledi occupied caves -- probably as a salt-
> miner. It never needed to swim, and when it
> rained, H.naledi stayed safe and dry.

Occam's Razor

We find them in a cave, why not assume they live in a cave?

Oddly, nobody ever once found a fossil on a savannah and assumed that
it lived on a beach and only wandered onto the savannah because it
dropped it's watch and it thinks it remembers having it when it was visiting
Zoe Zebra on the savannah...

-- --

https://uapro.tumblr.com/post/653831069175562240/channeling-gary-lesley

On Sunday 13 June 2021 at 02:03:07 UTC+1, DD'eDeN aka note/nickname/alas_my_loves wrote:

>>> I can't opine about salt mining, no idea. But long-term cave
>>> dwelling would seem to select *for* sound amplification and
>> > vision loss, unless torches were used.
>>
>> Torches were used.
>
> Speculation or evidenced?

It's a reasonable conclusion from all the evidence.
These caves are near Johannesburg, and had been
thought to be thoroughly explored. But remote,
and barely accessible chambers were then found,
with hominin fossils. H.naledi was a far better
spelunker than most highly experienced human
ones. Light is essential for the activity. Getting
lost is easy and fatal.

Secondly, the species clearly evolved into a
specialised 'spelunking niche'. It's physically
smaller than other hominins of its time, but it
also has a much smaller head (and brain).

>> Their fossils are found deep
>> within the caves, where there is absolutely no
>> natural light.
>
> Light reception is not absolutely necessary, taste is absolutely
> necessary to harvest salt, sound reception is probably likely
> (group spelunking).

Light is essential. Those caves are remote, and
even with light, getting in and out is difficult.

>> That would have meant foraging
>> (or trading) for the necessary torch materials.
>
> Physical evidence?

The presence of their dead in remote
chambers is more than enough.

On Sunday, June 13, 2021 at 9:00:53 AM UTC-4, Paul Crowley wrote:
> On Sunday 13 June 2021 at 02:03:07 UTC+1, DD'eDeN aka note/nickname/alas_my_loves wrote:
>
> >>> I can't opine about salt mining, no idea. But long-term cave
> >>> dwelling would seem to select *for* sound amplification and
> >> > vision loss, unless torches were used.
> >>
> >> Torches were used.
> >
> > Speculation or evidenced?
> It's a reasonable conclusion from all the evidence.
> These caves are near Johannesburg, and had been
> thought to be thoroughly explored. But remote,
> and barely accessible chambers were then found,
> with hominin fossils. H.naledi was a far better
> spelunker than most highly experienced human
> ones. Light is essential for the activity. Getting
> lost is easy and fatal.
>
> Secondly, the species clearly evolved into a
> specialised 'spelunking niche'. It's physically
> smaller than other hominins of its time, but it
> also has a much smaller head (and brain).
> >> Their fossils are found deep
> >> within the caves, where there is absolutely no
> >> natural light.
> >
> > Light reception is not absolutely necessary, taste is absolutely
> > necessary to harvest salt, sound reception is probably likely
> > (group spelunking).
> Light is essential. Those caves are remote, and
> even with light, getting in and out is difficult.
> >> That would have meant foraging
> >> (or trading) for the necessary torch materials.
> >
> > Physical evidence?
> The presence of their dead in remote
> chambers is more than enough.
Many fauna seek salt in exposed soil and caves using available senses, no torches. No physical evidence of combustion.

On Sunday 13 June 2021 at 22:30:40 UTC+1, DD'eDeN aka note/nickname/alas_my_loves wrote:

>> Light is essential. Those caves are remote, and
>> even with light, getting in and out is difficult.
>>
>>>> That would have meant foraging
>>>> (or trading) for the necessary torch materials.
>>>
>>> Physical evidence?
>> The presence of their dead in remote
>> chambers is more than enough.
>
> Many fauna seek salt in exposed soil and caves using available senses,
> no torches. No physical evidence of combustion.

Indeed, including elephants which
use their tusks to scrape ceilings.
But I doubt if any species go in so
far as to lose sight of the light which
shows them their way out.

You're obviously unfamiliar with the
reports of the H.naledi investigations.
They found no fossil remains of any
species other than hominins at any
distance from the entrance, with the
exception of the remains of one bird
at a point less than halfway in (as
compared to the location of the
hominin fossil chamber).

> No physical evidence of combustion.

Burnt or unburnt torches made ~0.5 ma
would long ago have turned to dust.