If animals could use the suns energy they wouldnt need to fat plants. Cut out the middleman. Stylish should understand
Of course it would be more efficient for animals to be able to use sun's energy.
But there are some disadvantages:
1. THERE WILL BE NO OXYGEN PRODUCING TREES!!! People would die!
2. No natural beauty from plants.
3. No zoo business
4. No great taste of food products. In time, we would not have any tounge because that will be unnecessary and we will not develop that way. It will look odd.
I think the first reason is solid enough to prove my point...