AND PERSONALITY 



Shark 



Heart 291.5 grams 



Thyroid gland 

 12.73 grams 



Porpoise 



Brain 1735.69 grams 



Heart 737.5 grams 



Thyroid gland 

 18.29 grams 



Adrenal glands 

 10.41 grams 

 Fie. 13. A comparison of the energy-controlling organs of a shark and a porpoise. 



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