Structure/function  Human                    Dolphin
------------------  ------------------       ----------------------
Bodies              Mammalian: head,         Mammalian: neutral
                    hands, arms, legs,       buoyancy, swimming
                    manipulatory,            adaptations, head,
                    walking, running         flippers, flukes:
                    in-air adapations:       streamlined shape
                    nonstreamlined shape

Brains              900-1,800 grams:         1,000-6,000 grams:
                    1400 grams average;      present size 25
                    present size 0.1         million years.
                    million years.           Predominatly
                    Predominatly             associational
                    associational            cerebral cortex.
                    cerebral cortex.

Locomotion          Discontinuous,           Free dive limit
                    with sleep periods       continuous process:
                    interrupting; no         moving to surface for
                    movement for long        every breath, swimming
                    periods. Maximum         24 hrs/day whole life.
                    velocity about 18        Average 5 knots:Max
                    knots running.           velocity about 30

Sexuality           Carefully                Free expression:
                    regulated: can take      voluntary erection of
                    place at any time.       penis in males. Can
                    Ritualized clothing,     take place at any
                    behaviour, male vs.      time. Fertilization
                    female.                  at time to give birth
                                             during warm season.

Birth and           Gestation 9 months.      12 months gestation.
Reproduction        Birth into air.          Underwater birth.

Respiration         Always available air:    Air must be sought
                    automatic continuance    at surface; must wake
                    during unconsciousness,  up for every breath; 
                    sleep, anesthesia.       no automatic
                                             continuance in sleep,

Nutrition           Plants, animals:         Fish, shrimp, squid:
                    predigestion by cooking. raw (no cooking)

Circulation         Upright position         Horizontal, buoyancy
                    adaptation: no rete      adaptation rete
                    mirabile                 mirabile for emergency
                                             brain functioning.

Communication       Outputs: 2 sources       Outputs: adapted to
                    with sequence control:   underwater emission:
                    Air-speech; written      3 sources independent
                    materials                control. Underwater
                    Inputs: ears adapted     sound communication;
                    to air: azimuth and      no written forms.
                    elevation detection:     Sound emission for
                    scanning.                ranging, recognition
                                             and orientation.
                                             Inputs: ears adapted
                                             to underwater azimuth
                                             and elevation:

Evolution:          Evolved from prehuman    Evolved from
                    forms over last          predolphin forms last
                    million years.           50 million years.

Organization:       Economic exploitation    Total interspecies
                    of ecology: financial    interdependence; in
                    records rule.            ecological harmony.

Ethics:             Human-centered: no       Dependence on others:
                    other species directed.  no aggressivity, no
                                             hostile attacks.

Nonbrain, Outside   Human reality            None. 
Records:            constructed in written

Gonads:             Male: external testes,   Male: internal testes,
                    external penis.          internal penis.
                    Female: internal         Female: internal
                    ovaries, interal         ovaries, internal
                    uterus.                  uterus.

Mating:             Male erection:           Male erection:
                    involuntary.             voluntary.
                    Female estrus:           Female estrus:
                    monthly                  monthly (?)
                    Copulation:              Copulation:
                    voluntary, any time      voluntary, any time
                    Insemination:            Insemination:
                    depends on fertility     depends on fertility
                    cycle in female:         cycle in female:
                    sperm -} egg.            sperm -} egg.

Gestation:          9 months.                12 months.
                    Intrauterine embryo,     Intrauterine embryo,
                    placentation.            placentation.
                    Embryo -} fetus -}       Embryo -} fetus -}
                    birth.                   birth.

Birth and           Uterine fetus -}         Uterine fetus -}
First Breath:       baby in canal -}         baby in canal -}
                    air-gravity environment. seawater buoyant
                    First breath in air      environment. For first
                    surrounding body. No     breath must reach air
                    need for immediate       at seawater surface.
                    mobility.                Must swim within few
                                             minutes of emersion
                                             from canal.

Brain and           At birth 300 grams.      At birth 600 grams.
First Survival      Automatic respiratory    Automatic respiratory
Programs:           circuits operating       circuits released at
                    after first breath       first breath. Control
                    releasing them. No       of respiratory acts
                    locomotory circuits      must be coordinated
                    yet completely           with surfacing of
                    operative. Cries and     blowhole in air.
                    coos.                    Coordination of
                                             locomotion to surface
                                             with breathing:
                                             patterning developed
                                             within first 6
                                             minutes. Whistles and
                                             harsh noises.

Suckling:           Mother places baby's     Swimming baby has fat
                    mouth on nipple,         stores for initial
                    elicits suckling         nutritional needs.
                    pattern ("releaser")     Mother presents
                    by lip stimulation.      mammary-genital region
                                             to tip of baby's
                                             rostrum, elicits
                                             suckling pattern after
                                             first few hours.

Infancy:            Mother carries,          Mother stays with,
                    fondles, protects,       protects, strokes,
                    feeds, teaches baby      swims with, teaches
                    (human speech within     baby dolphin-
                    first 1.5-5 years).      necessitites for first
                                             2 years and longer.

Speech:             First words: 18 months   Initial sounds:
                    to 2 years. Cooing -}    distress whistle for
                    vowel sounds. Practice   calling mother,
                    of phons for first 18    "putts" for
                    months.                  localization (release
                                             air from blowhole). At
                                             9 months postpartum,
                                             control of clicking
                                             without air loss
                                             matures. Whistle
                                             control suddenly 

Sonic Window:       20 to 15,000 Hz          100 to 150,000 Hz

Communication       300 to 3,000 Hz          1,000 to 80,000 Hz

Timing:             0.001 to 0.00001 sec     0.0001 to 0.000001
                                             sec. Overlap limited.

Electromagnetic     0.3 to 0.7 micrometres   Unknown. Evidence of
Radiation Window:                            definite overlap.

Gravitation         Adapted to (1+)g         Adapted to near-
Window:             (bipedal locomotion)     neutral buoyancy:
                                             Out of water
                                             action impeded

Temperature         37 degrees C (98.6 F)    37 degrees C (98.6 F)
Brain:              32C - 44C                (limits unknown)
Skin:               5C - 50C                 (unknown)

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