Dive Song

This is a brief theoretical interpretation of a typical diving-foraging event of ancestral seashore humans.
[Unfinished as of Feb. 2007, copywrite 02/07/07, David Deden, Director-Naturalist-Author, THE-ARC]

{Warning: This is not diving instructions for modern humans. For more information, contact the Author.}

Abbrev. D-F: Dive-Forage/r/s/ing, B-F: Back-Float/er/s/ing, M: Male, F: Female, B: Baby

B always at water surface, on M/F thighs or chest, holding hair, beard, breast.
Dive cycle = From surface, descent to D-F at bottom, then ascent to surface for a short rest B-F.
Dive series = between 3 - 7 (ave. 5) dive cycles, then long rest aerobic eupnea B-F while partner D-F.

2 likely types of dive series:
Alternate series: Same as Batch, except after each single dive, switch diver, after each does 5 dives, they both rest (eat?).
Batch series: Starting at 20m depth, M D-F 5 times while F B-F with B, then F D-F 5 times while M B-F with B, then M again dives, etc., each single dive is a bit shallower, holding or throwing the food to shore, until they end nearby the shore, then go bask in the sand under a palm tree and eat seafood, fruit, coconut (or eat while B-F depending on waves, etc.) and rest.

Significant traits:

1) B-F humming: calms B, informs D-F of B-F position and status via bone conduction (no need for D-F to look upwards), removes excess Nitrogen(?) as Nitric Oxide produced in sinuses kills nasal aquatic microbes, keeps nostrils open yet excludes water due to nose exhale, lullabye and gentle wave rocking motion keeps B at rest.

2) D-F clicking: informs B-F of D-F position and status via bone conduction (no need for B-F to look down), retains air in mouth, trachea and 1/2 filled lungs, oral airway velum valve (soft palate) closed to flooded nasal & sinus compartments, diver never in B-F postion during dive so velum not upside-down (potentially hazardous).

3) Both B-F and D-F have inner, middle, outer aural cavities flooded, and during entire diving period ears remain submerged.

4) Clicking and humming are two dissimilar sounds, not dissonant or conflicting; function as primitive positional sonar (not fish-finding, more like cave swifts), both B-F & D-F can transmit and receive simultaneously due to different sound frequency and wavelength channels. Possibly B-F oral exhale whistling (siren?) was used as well (dolphins whistle inter-narially (closed nose) due to nasal air sacs).

5) Emergency signals: Wide open eye (white) contact, D-F "quack-barks" & stops clicking, B-F yells, whistles & splashes palm down (beaver tail), both have knife/spatula tool. If D-F has a problem below (shark), B-F alarms others, lets the B B-F, and dive straight down with knife/spatula tool.

Dive series: M starts at deepest desired depth, F B-F above him as a positional buoy, F accepts seafood "gifts" (and colorful coral trinkets) from him with each ascent. While F floats, her head is tilted back a bit, nose is highest point, ears submerged listening, eyes closed or slitted, baby nursing at breast or asleep on her thighs, as F hums or sings a lullabye (Asian tonal language root). This humming calms B, produces antibiotic NO in the F sinus nasal airways, and communicates in an aerobic oral-nasal underwater version of "whale song". M below hears the humming until a certain depth and knows F and B are okay, he makes clicking sounds (retained in Khoisan click language root) which she hears just under the surface.

After making 5 dives (= 1 dive series), moving slightly shallower with each dive, they switch places, M rests B-F and (possibly throwing seafood to the dry shore) humming to B while F D-F and clicks. They continue until sufficient food is gathered and arrive at shallows, eat and rest on beach.

The essence of this partnership is what allowed our seashore ancestors to embrace monogamy, while one foraged, the other floated above with the baby, unseen but heard, with communication both ways providing information, safety and love.