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Science Forum Index » Anthropology - Paleo Forum » H.erectus = hyperostosis "incompatible with safe...
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| Marc Verhaegen... |
 Posted: Tue Jul 15, 2008 6:03 pm |
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Savanna Fantasies:
A possible case of hypervitaminosis A in Homo erectus
A Walker, MR Zimmerman & R Leakey 1982 Nature 296:248-250
Following an initial discovery by K.Kimeu in 1973, sieving operations have
recovered the most complete H.erectus skeleton so far known (Fig.1) from the
Upper Member of the Koobi Fora Formation in Area 103, Koobi Fora, East Lake
Turkana in Kenya. The partial skeleton shows pathological changes consistent
with chronic hypervitaminosis A. We attribute this disorder to the high
dietary intake of animal liver, most probably that of carnivores, during a
period when the dietary habits of Homo erectus were changing.
ER-1808 female? striking "pathology":
- sub-perioseal diaphyseal deposit of coarse-woven bone
- 7 mm in places
- minimal endocranial involvement
- tibia: confined to the outermost cortex
- enlarged, sub-spherical & randomly-placed lacunae
- no abnormal remodelling of the underlying bone
- dense mineralisation
(The authors think ER-1808 suffered from hypervit.A, but there is bony
resorption in hypervit.A. It's many times more parsimonious that the bone
thickening (seen in +-all H.erectus specimens) is not pathological, but has
the same explanation as in other thick-boned mammals: slow diving. After
all, the earliest H.erectus were found next to rich aquatic resources (eg,
molluscs) & H.erectus dispersed between Algeria & Java along the coasts.)
_____
Simple biological facts:
Sink or swim?
Bone density as a mechanism for buoyancy control in early cetaceans
N-M Gray cs 2007 Anat Rec 290:638-653
.... secondarily aquatic tetrapods, including whales, exhibit osteological
adaptations to life in water as part of their complex buoyancy control
systems ... Bone histology was examined from the ribs of 10 fossilized
individuals representing 5 early cetacean families (Pakicetidae,
Ambulocetidae, Protocetidae, Remintonocetidae, Basilosauridae). Comparisons
were then made with rib histology from 9 genera of extant mammals including:
Odocoileus (deer), Bos (cow), Equus (horse), Canis (dog), Lutra (river
otter), Enhydra (sea otter), Choeropsis (pygmy hippo), Trichechus (sea cow),
Delphinus (dolphin). Results : the transition from terrestrial, to
semiaquatic, to obligate aquatic locomotion in archaeocetes involved a
radical shift in bone function achieved by means of profound changes at the
micro-structural level. A surprising finding : microstructural change
predates gross anatomical shift in archaeocetes associated with swimming.
Histological analysis shows
- high bone density is an aquatic specialization that provides static
buoyancy control (ballast) for animals living in shallow water ;
- low bone density is associated with dynamic buoyancy control for animals
living in deep water.
Thus, there was a shift from the typical terrestrial form, to osteopetrosis
& pachyosteosclerosis, and then to osteoporosis in the first quarter of
cetacean evolutionary history.
.... dramatic modifications occur in the structural properties of bone
tissue, ranging across extremely high to extremely low density (review
Ricqles & Buffrenil 2001). These adaptations are recognized as variable
strategies for managing buoyancy (Taylor 2000). The earliest examination of
fossil cetacean bone (40 Ma fully aquatic taxa Basilosaurus & Zygorhiza)
indicated : both possess pachyosteosclerotic ribs, similar to modern members
of Sirenia. But with few exceptions, modern Cetacea universally exhibit
osteoporotic bone in all skeletal elements but the vertebrae & skull.
.... It is now possible to examine bone from the 10-My period preceding
Basilosaurus & Zygorhiza, which includes 4 additional archaic cetacean
families: (from oldest to youngest) Pakicetidae, Ambulocetidae,
Remingtonocetidae, Protocetidae.
1) Pakicetidae : Early Eocene, stream deposits. While their skeletons were
originally described as adapted for running, subsequent detailed analysis of
the postcrania noted systemic hyperostosis, a condition incompatible with
safe, energetically efficient cursoriality.
2) Ambulocetus : Middle Eocene, transitional marine environments. More
overt specialization toward aquatic locomotion : lengthened distal limb
segments ; axial modifications related to dorso-ventrally propulsed aquatic
locomotion. Osteosclerotic long bones.
3) Remingtonocetidae & Protocetidae : Middle Eocene, bridge the gap between
the earliest freshwater & marine cetaceans.
4) Basilosauridae : Middle - late Eocene (contain the sister group to all
modern cetaceans). 2 subfamilies: Basilosaurus (basilosaurinae) & Zygorhiza
(dorudontinae = essentially modern cetacean body form: more flipper like
forelimbs, tremendously reduced hind limbs, advanced vertebral column
(oscillatory swimming ; presence of a tail fluke). |
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| Lee Olsen... |
| Posted: Tue Jul 15, 2008 6:03 pm |
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On Jul 15, 4:03 pm, Marc Verhaegen <m_verhae... at (no spam) skynet.be> wrote:
Quote: Simple biological facts:
Sink or swim?
Correct answer, sink. Better to run.
A ARON G. F ILLER
Emergence and optimization of upright
posture among hominiform hominoids
and the evolutionary pathophysiology of
back pain
Neurosurg. Focus / Volume 23 / July, 2007
"The effects of these three major types of transformation
is an increase in the degree of dynamic, muscularly driven
compressive forces on lumbar disks and a greater risk for
strains and tears in the muscles of the lumbar region be-
cause of their increased leverage. These features are evo-
lutionary innovations that suit the human body plan as
well as the evolutionary path and lifestyle of the human
lineage. They have supported an upright bipedal species
capable of carrying heavy objects and the young across
great distances, whether walking or running. In this fash-
ion they have helped our species to more or less conquer
the world. Nonetheless, these changes seem to be the prin-
cipal suspects for any relative increase in the susceptibili-
ty to back pain that humans may exhibit relative to the
other mammalian species."
W.-J. Wang and R. H. Crompton
The role of load-carrying in the evolution of modern body
proportions
J. Anat. (2004) 204 pp417–430
Abstract
The first unquestionably bipedal early human ancestors, the species
Australopithecus afarensis,
were markedly
different to ourselves in body proportions, having a long trunk and
short legs. Some have argued that
chimpanzeelike features such as these suggest a ‘bent-hip, bent-
knee’ (BHBK) posture would have been adopted during gait.
Computer modelling studies, however, indicate that this early human
ancestor could have walked in a reasonably
efficient upright posture, whereas BHBK posture would have nearly
doubled the mechanical energy cost of locomotion,
as it does the physiological cost of locomotion in ourselves. More
modern body proportions first appear
at around 1.8–1.5 Ma, with Homo ergaster (early AfricanHomo erectus),
represented by the Nariokotome skeleton
KNM-WT 15000, in which the legs were considerably longer in relation
to the trunk than they are in human adults,
although this skeleton represents an adolescent.
Several authors have suggested that this morphology would have
allowed faster, more endurant walking. But during the same period, the
archaeological record indicates a sharp
rise in distances over which stone tools or raw materials are
transported. Is this coincidental, or can load-carrying
also be implicated in selection for a more modern morphology? Computer
simulations of loaded walking, verified
against kinetic data for humans, show that BHBK gait is even more
ineffective while load-carrying. However, walking
erect, the Nariokotome individual could have carried loads of 10–15%
body mass for less cost, relative to body
size, than AL 288-1 walking erect but unloaded. In fact, to the extent
that our sample of humans is typical, KNMWT
15000 would have had better mechanical effectiveness in bearing light
loads on the back than modern human
adults. Thus, selection for effectiveness in load-carrying, as well as
in endurant walking, is indeed likely to have
been implicated in the evolution of modern body proportions.
Quote: Bone density as a mechanism for buoyancy control in early cetaceans
N-M Gray cs 2007 Anat Rec 290:638-653
... secondarily aquatic tetrapods, including whales,
Wetloons think they are whales?
Read the facts here:
http://www.aquaticape.org/ |
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| Lee Olsen... |
| Posted: Wed Jul 16, 2008 3:55 am |
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On Jul 16, 4:19 am, Marc Verhaegen <m_verhae... at (no spam) skynet.be> wrote:
Quote: Simple biological facts:
Sink or swim?
Our little SF snipped the evidence,
Wetloon, your imagination is not evidence. Here are the facts:
Mujin wrote:
Quote: [...]
"Conclusions: Running, a weight-bearing exercise, is associated with more
favorable geometric and biomechanical characteristics in relation to bone
strength, compared with the weight supported activities of swimming and
cycling. Differences may reflect skeletal adaptations to the specific
mechanical-loading patterns inherent in these sports"
http://www.acsm-msse.org/pt/re/msse/abstract.00005768-200204000-
00018.htm;jsessionid=HJxhg51XTP76vm2Q2tjGNy9JTQCZFcv3xHG8Qh2XL470Kzjk7kPB!-
1601909834!181195629!8091!-1
Clearly weight bearing, high impact activity increases cortical thickness
and decreases medullary cavity sizes. More importantly:
See also
http://www.ncbi.nlm.nih.gov/pubmed/10949001
Total and regional bone density in male runners, cyclists, and
controls.
Medicine & Science in Sports & Exercise. 32( :1373-1377, August
2000.
...
Conclusion: Running is associated with increased bone density,
particularly in
the leg, whereas cycling is associated with a mild decrease in bone
density in
the spine. In athletes who do both, running exerts a stronger
influence than
cycling.
Quote:
Correct answer, sink. Better to run.
Not if you're as heavy & fat as erectus was.
Noel T. Boaz Page 138: "He showed that even the slowest
human runners could, with even a slight head start, outrun lions,
cheetahs, leopards, hyenas, and wild dogs, not by speed, but by out
distancing them."
http://tinyurl.com/32ezcs
"What advantage did it give us during our evolution?
One possibility is that our posture is a reasonable compromise, a way
to derive a relatively efficient terrestrial mode from an ape-like
body. We evolved this way because it allows us to walk long
distances.
Another possibility described in a new paper by Bramble and Lieberman
is that our posture is an adaptation for high-performance endurance
running, and that really we're a species of lopers, joggers, and
marathon runners."
Please try to think at least a
little bit.
Quote:
AARON G. FILLER
Emergence and optimization of upright
posture among hominiform hominoids
and the evolutionary pathophysiology of
back pain
Neurosurg. Focus / Volume 23 / July, 2007
"The effects of these three major types of transformation
is an increase in the degree of dynamic, muscularly driven
compressive forces on lumbar disks and a greater risk for
strains and tears in the muscles of the lumbar region be-
cause of their increased leverage. These features are evo-
lutionary innovations that suit the human body plan as
well as the evolutionary path and lifestyle of the human
lineage. They have supported an upright bipedal species
capable of carrying heavy objects and the young across
great distances, whether walking or running. In this fash-
ion they have helped our species to more or less conquer
the world. Nonetheless, these changes seem to be the prin-
cipal suspects for any relative increase in the susceptibili-
ty to back pain that humans may exhibit relative to the
other mammalian species."
Yes, Filler convincingly agues that a verticdal spine was already 20 Ma old.
Yep, and stone tools are all over the savanna before they were at the
beach.
Your program is just backwards. |
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| Marc Verhaegen... |
| Posted: Wed Jul 16, 2008 6:19 am |
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Guest
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Quote: Simple biological facts:
Sink or swim?
Our little SF snipped the evidence, but thought he should write:
Quote: Correct answer, sink. Better to run.
Not if you're as heavy & fat as erectus was. Please try to think at least a
little bit.
Quote: AARON G. FILLER
Emergence and optimization of upright
posture among hominiform hominoids
and the evolutionary pathophysiology of
back pain
Neurosurg. Focus / Volume 23 / July, 2007
"The effects of these three major types of transformation
is an increase in the degree of dynamic, muscularly driven
compressive forces on lumbar disks and a greater risk for
strains and tears in the muscles of the lumbar region be-
cause of their increased leverage. These features are evo-
lutionary innovations that suit the human body plan as
well as the evolutionary path and lifestyle of the human
lineage. They have supported an upright bipedal species
capable of carrying heavy objects and the young across
great distances, whether walking or running. In this fash-
ion they have helped our species to more or less conquer
the world. Nonetheless, these changes seem to be the prin-
cipal suspects for any relative increase in the susceptibili-
ty to back pain that humans may exhibit relative to the
other mammalian species."
Yes, Filler convincingly agues that a verticdal spine was already 20 Ma old.
Think, my little boy:
early apes = vertical spine + arm-hanging = swamp forests, exactly where all
early apes were found. Filler nicely confirms our TREE paper: google
"aquarboreal".  Ideal preadaptation for a waterside omnivorous Homo. |
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| Lee Olsen... |
| Posted: Wed Jul 16, 2008 11:56 am |
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On Jul 16, 12:06 pm, Marc Verhaegen <m_verhae... at (no spam) skynet.be> wrote:
Quote: Noel T. Boaz Page 138: "He showed that even the slowest
human runners could, with even a slight head start, outrun lions,
cheetahs, leopards, hyenas, and wild dogs
:-DDD
In what century did Boaz write that nonsense??
Asks who, the imbecile who thinks mountain beavers are semiaquatic?
Read it weep you delusional wetloon:
http://www.man-eater.info/gpage6.html
VI. Vegetation and Habitat factors
"Cover can also be an important factor when lions stalk people. Taylor
asserts (1959) that a lion will never attack a person across a wide
opening.
Dense cover facilitates attacks by ambush predators (Mitchel, et al.
1965; Schaller, 1972; Prinns, 1996; Funston, et al. 2001). Even in the
open Serengeti ecosystem, Schaller documents that 75% of lion kills
occur near cover. Favoured areas include thickets, tall grasslands,
and woodlands. Despite relatively small areas encompassing these
habitats, 40-41% of all kills occurred near rivers where dense
vegetation and broken terrain facilitate ambush. Lion predation on
buffalo was especially focused on river edges."
Near "river edges" is the best place to camp if you want to die
young.
Pervert.
Quote: instead of telling us fairy tales, you better listen to
simple biological facts:
The worst place for early Homo was streamside.
Here read it again, you probably didn't understand it the first time:
http://www.man-eater.info/gpage6.html
"VI. Vegetation and Habitat factors
Cover can also be an important factor when lions stalk people. Taylor
asserts (1959) that a lion will never attack a person across a wide
opening.
Dense cover facilitates attacks by ambush predators (Mitchel, et al.
1965; Schaller, 1972; Prinns, 1996; Funston, et al. 2001). Even in the
open Serengeti ecosystem, Schaller documents that 75% of lion kills
occur near cover. Favoured areas include thickets, tall grasslands,
and woodlands. Despite relatively small areas encompassing these
habitats, 40-41% of all kills occurred near rivers where dense
vegetation and broken terrain facilitate ambush. Lion predation on
buffalo was especially focused on river edges." |
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| Marc Verhaegen... |
| Posted: Wed Jul 16, 2008 1:45 pm |
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Guest
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Quote: Simple biological facts:
Sink or swim?
Our little SF snipped the evidence,
Wetloon, your imagination is not evidence.
the text of the authors, my little boy |
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| Lee Olsen... |
| Posted: Wed Jul 16, 2008 1:52 pm |
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On Jul 16, 4:06 pm, Marc Verhaegen <m_verhae... at (no spam) skynet.be> wrote:
Quote: Savanna Fool now runs after lions... 
No wetloon, you *stay away* from streamside and you won't get bit.
"The common presence of large
predators, especially in the late dry season,
makes them dangerous places, especially at
night, even for hunters in thorn-walled
blinds. Women and children rarely visit
these locations after dark. Among the
Hadza, base camps are almost always established
in other settings, 10–20 minutes
walk from permanent water, generally
outside riparian habitats, especially in the
dry season."
J. F. O’Connell et al.
Male strategies and Plio-Pleistocene
archaeology
Journal of Human Evolution (2002) 43, 831–872
Quote:
On Jul 16, 12:06 pm, Marc Verhaegen <m_verhae... at (no spam) skynet.be> wrote:
Noel T. Boaz Page 138: "He showed that even the slowest
human runners could, with even a slight head start, outrun lions,
cheetahs, leopards, hyenas, and wild dogs
:-DDD
In what century did Boaz write that nonsense??
Asks who, the imbecile who thinks mountain beavers are semiaquatic?
Read it weep you delusional wetloon:
http://www.man-eater.info/gpage6.html
:-D |
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| Marc Verhaegen... |
| Posted: Wed Jul 16, 2008 2:06 pm |
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Quote: Noel T. Boaz Page 138: "He showed that even the slowest
human runners could, with even a slight head start, outrun lions,
cheetahs, leopards, hyenas, and wild dogs
:-DDD
In what century did Boaz write that nonsense??
My little boy, instead of telling us fairy tales, you better listen to
simple biological facts:
"Sink or swim? Bone density as a mechanism for buoyancy control in early
cetaceans" N-M Gray cs 2007 Anat Rec 290:638-653
.... While their (Pakicetidae) skeletons were originally described as adapted
for running (cf. enduring running nonsense: sounds familiar...), subsequent
detailed analysis of the postcrania noted systemic hyperostosis (as in
H.erectus), a condition incompatible with safe, energetically efficient
cursoriality.
Got it, my little boy?? |
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| Lee Olsen... |
| Posted: Wed Jul 16, 2008 3:57 pm |
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Guest
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On Jul 16, 5:42 pm, Marc Verhaegen <m_verhae... at (no spam) skynet.be> wrote:
Quote: Savanna Fool now runs after lions...
No wetloon, you *stay away* from streamside and you won't get bit.
:-D
you're just stupid stupid stupid, olson boy
Name calling, only argument you have left. |
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| Marc Verhaegen... |
| Posted: Wed Jul 16, 2008 6:06 pm |
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Savanna Fool now runs after lions... :-D
Quote: On Jul 16, 12:06 pm, Marc Verhaegen <m_verhae... at (no spam) skynet.be> wrote:
Noel T. Boaz Page 138: "He showed that even the slowest
human runners could, with even a slight head start, outrun lions,
cheetahs, leopards, hyenas, and wild dogs
:-DDD
In what century did Boaz write that nonsense??
Asks who, the imbecile who thinks mountain beavers are semiaquatic?
Read it weep you delusional wetloon:
http://www.man-eater.info/gpage6.html
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| Marc Verhaegen... |
| Posted: Wed Jul 16, 2008 7:42 pm |
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Quote: Savanna Fool now runs after lions... :-D
No wetloon, you *stay away* from streamside and you won't get bit.
:-D
you're just stupid stupid stupid, olson boy |
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