Field Report Bulbasaur, Ivysaur, & Venasaur

Bulbasaur
This pokémon hatches with a large bulb attached to its back, which it uses to help it gather nutrients. It is it is thought that the bulb is not a biological part of the bulbasaur, rather a separate organism in a symbiotic relationship with the animal.

Bulbasaur evolves into ivysaur at level 16.

Ivysaur
The bulb sprouts into a flower at this stage, allowing for more nutrients to be gathered and given to the animal, causing it to grow larger and stronger. In return, ivysaur must drink much more water and stay in the sun for longer, but has to eat much less.

Ivysaur evolves into venasaur at level 32

Venasaur
In this stage, the plant has fully matured, allowing for the animal to grow much larger and more powerful. However, venasaur is much slower than its preevolutions in return for this bulk, and its water consumption must be very high to sustain the flower.