Reptiles

1. Ectothermic
   1. Lower MR

      Nota:

      • than birds + mammals.  Less water lost via breathing 
   2. Nocturnal
2. Skin = impermeable
   1. Increase lipids
3. Relatively small
   1. Fossorial

      Nota:

      •  - escape harsh conditions
4. Dehydration tolerant

   Nota:

   • Loss of 50% in some Geckos 
   1. Extra Renal Excretory Gland

      Nota:

      • Kidney can not deal with excess salt or produce hypertonic urine.     
      1. Nasal Salt Gland

         Nota:

         • Storage urates.  Secretes a fluid rich in potassium and sodium   Chamaeleo namaquensis
         1. Not seen in Mammals
5. Re-Absorbtion

   Nota:

   • Via Cloaca

Nota:

• TEWL - Transepidermal evaporative WL

Nota:

• Faeces and urine (mixed together)

1. Selective

   Nota:

   • Appropriate foods and favourable niches. Avoid high salt food 
2. Uricotelic

   Nota:

   • Produce Uric Acid witch is filtered by the salt glad. - not in mammals 
   1. Uric Acid

Nota:

• Milks or TOXINS 

1. Toxins in snakes

1. Diet
   1. Starvation tolerant

1. Aestivation

   Nota:

   • Tortoise - Excrete uric acid after AESTIVATION 

1. Thorny Devil

   Nota:

   • Moloch horridus  Thin capillary tracts run in parallel to the back of the animal, sucking up water to the mouth. 

1. Lizards