AtDTdA (9): 239

[David Morris]

On 5/14/07, Jasper <jasper.fidget at gmail.com> wrote:
> Brief summary:
> Crouchmas

http://www.youtube.com/watch?v=96eSrFlUVh0

http://www.dothecrouch.com/

http://members.aol.com/doder1/crouch1.htm

RESEARCH REPORTS: 1. In the dog: "Instead of walking upright, the body
sinks downwards or even crouches, and is thrown into flexuous
movements; his tail, instead of being held stiff and upright, is
lowered and wagged from side to side; his hair instantly becomes
smooth; his ears are depressed and drawn backwards, but not closely to
the head; and his lips hang loosely" (Darwin 1872:56). 2. Crouching
has been observed in subordinate bonnet macaques (Rahaman and
Parthasarathy 1968). 3. Motherless rhesus monkeys crouched and "showed
symptoms similar to disturbed mental patients" (Pugh 1977:200).

Paleontology I. The vertebrate crouch display is formed of ancient
bending motions designed to remove animals from danger. A reflexive
act, controlled by the spinal cord, bending the body moves it away
from hazards, reduces its exposed surface area, and makes it look
"smaller." Nonverbally, flexed body movements used to crouch lower to
the ground predate extension movements used to rise or lift above the
terrestrial surface (see, e.g., HIGH-STAND DISPLAY); thus, our remote
ancestors crouched before they stood tall.

Paleontology II. Crouching can be traced to an avoider's response,
which is tactile in origin rather than visual, as in the high-stand
display. So primitive is the crouch posture's flexor reflex that it
exists even in immature fish and amphibian larva. Stimulating the skin
of these simple creatures leads to side-to-side bending movements,
which, in a watery world, remove them from dangers signaled by the
touch.

Neuro-notes. The crouch is keyed to paleocircuits formed of primitive,
spinal-cord interneurons in charge of tactile withdrawal. Similar "tap
withdrawal" movements have been observed in spineless animals, such as
the nematode worm. Working through pools of interneurons controlling
the muscular stretch reflex, the worm's body, like ours, automatically
bends away from danger.

Antonym: Antigravity Posture

Paleontology. Fossils of the oldest known North-American amphibian,
Hynerpeton bassetti (365 m.y.a.), show that its hands and arms were
strong enough to do a pushup akin to the aggressive press-up posture
of today's lizards, basilisks, and iguanas. Hynerpeton's jointed
elbows might have permitted the animal to extend its forelegs in what
would have been Nonverbal World's first high-stand display. A mobile
shoulder girdle and muscular forelimbs would have enabled Hynerpeton
to lift its body higher above the earthly plain, to dominate, command
respect, and "take charge."

Neuro-notes. Our body's innate ability to show a superior, confident,
haughty attitude through postures engineered to withstand gravity's
force--i.e., to assume a higher stance upon the earthly plain--evolved
from paleocircuits of the amphibian brain. Antigravity extensor
muscles of the neck, trunk, arms, and legs contract when signals are
received from cerebellar and vestibular centers responding to pontine
reticular nuclei. The latter brain-stem circuits may be excited as
well by emotional stimuli from the limbic system.