Functional And Structural Comparison Of Man's Digestive Tract
With That Of A Dog And Sheep

  Man Dog Sheep
TEETH
Incisors Both Jaws Both Jaws Lower Jaw Only
Molars Ridged Ridged Flat
Canines Small Large Absent
JAW
Movements Vertical Vertical Rotary
Function Tearing-Crushing Tearing-Crushing Grinding
Mastication Unimportant Unimportant Vital Function
Rumination Never Never Vital Function
STOMACH
Capacity 2 Quarts 2 Quarts 8 1/2 Gallons
Emptying time 3 Hours 3 Hours Never Empties
Interdigestive rest Yes Yes No
Bacteria present No No Yes-Vital
Protozoa present No No Yes-Vital
Gastric acidity Strong Strong Weak
Cellulose digestion None None 70% - Vital
Digestive activity Weak Weak Vital Function
Food absorbed from No No Vital Function
COLON & CECUM
Size of colon Short-Small Short-Small Long-Capacious
Size of cecum Tiny Tiny Long-Capacious
Function of cecum None None Vital Function
Appendix Vestigial Absent Cecum
Rectum Small Small Capacious
Digestive activity None None Vital function
Cellulose digestion None None 30%-Vital
Bacterial flora Putrefactive Putrefactive Fermentative
Food absorbed from None None Vital Function
Volume of feces Small-Firm Small-Firm Voluminous
Gross food in feces Rare Rare Large Amount
GALL BLADDER
Size Well-Developed Well Developed Often Absent
Function Strong Strong Weak or Absent
DIGESTIVE ACTIVITY
From pancreas Solely Solely Partial
From bacteria None None Partial
From protozoa None None Partial
Digestive efficiency 100% 100% 50% or Less
FEEDING HABITS
Frequency Intermittent Intermittent Continuous
SURVIVAL WITHOUT
Stomach Possible Possible Impossible
Colon and cecum Possible Possible Impossible
Microorganisms Possible Possible Impossible
Plant foods Possible Possible Impossible
Animal protein Impossible Impossible Possible
RATIO OF BODY LENGTH TO:
Entire digestive tract

1:5

1:7

1:27

Small intestine

1:4

1:6

1:25

From: The Stone Age Diet: Based on in-depth studies of human ecology and the diet of man pgs.44-45, Walter L. Voegtlin, M.D., F.A.C.P. 1975 Vantage Press, NY, NY. This page HTML coding done by Brett Saks in October 1998.