2. Dearolf (2003)

3. Dearolf et al. (2000)

4. Dearolf et al. (2000)

5. Conclusions Dolphins are a Condition “3.5” neonate
Lower IMD than wildebeest
Lower IND than tamarin and wildebeest
Neonatal profile 95% of adult slow-twitch profile

6. Neonatal dolphins
26% of their body mass is
invested in blubber
vs. 20% in adults

7. Bottlenose dolphins
Nurse for 2.7 to 8 years
~ 70% weaned by age 4
Mann et al. (2000)

9. Problem and Solutions Problem:
Heat conductivity of water 25x that of air
Solutions?

10. Solutions  Insulation Marine mammals - two forms of insulation Fur
Blubber

11. Harbor porpoise blubber Spotted dolphin blubber
Still Air
Dry Fur
1.5
Sea otter hair, Wet
1.0
Wood
INSULATION (W-1M2oC)
Harbor porpoise blubber
Adipose
0.5
Spotted dolphin blubber
Muscle
Water
Copper 10 30 50 70 90
110
INSULATION THICKNESS (mm)

12. Polar bear hair, Dry Polar bear hair, Wet
Still Air
Dry Fur
1.5
Polar bear hair, Dry
Polar bear hair, Wet
1.0
Wood
INSULATION (W-1M2oC
Adipose
0.5
Muscle
Water
Copper 10 30 50 70 90
110
INSULATION THICKNESS (mm)

13. Thermal Windows
Dorsal fin
Pectoral flippers
Tailflukes
Feet
Flippers

14. Rommel et al., ‘98