Question

An animal had the following teeth; on the upper jaw, no incisors, no canines, six premolars and six molars. On the lower jaw, 6 incisors, no canines, six premolars and six molars.

1. Write down it’s dental formula. 
2. Suggest the mode of nutrition of this animal
3. Give a reason for your answer above. 
4. State two adaptations of the animal whose dental formula you have written above.

Answer 1

1. I  ⁰/₀ , C ⁰/₀, pm ³_/3, m ³/₃ 
      
2. Herbivorous.
3.     
   • Lacks incisors on upper jaw.
   • Lacks canines on both jaws/ has diastema.
4.  
   • Enamel open at the top crown to allow continuous growth.
   • Has diastema to create space for manipulation of food by tongue during chewing.
   • Presence of horny pad on upper jaw against which incisors on lower jaw cut off vegetation.
   • Jaws joined to allow sideways movement of the jaws during chewing.

Answer 2

60

Answer 3

Heterotrotrophism

Answer 4

It has no upper incisors and canines

Answer 5

It feeds on purely vegetations
It has a horny pad and a disstema