Why does Mr. Patel say that animals are "conservative, one might say even reactionary"? in the book Life Of Pie

Mr Patel says it because he learns that animals do not adopt as fast as humans when he is stuck on a boat with them.

Explanation:

Mr Patel is stuck with a few animals in a boat right in the middle of pacific.

He himself is able to adapt to the situations with some difficulty but rather quickly. The animals on the other hand find themselves out of depth and cannot figure out how to live on a boat.

This makes Patel realize that animals are in general conservative and reactionary as they only react as things happen and do not adapt as quickly.