Biological organisms (such as animals or plants) are the main examples of _intelligent_ systems that we are aware of (excluding artificially intelligent systems, so as not to discuss whether current AI systems are really intelligent or not). Consequently, biological life is often an inspiration for AI researchers to develop AI systems. 

There are numerous examples of AI systems that have been introduced  (at least, partially) _based on_ or just _inspired by_ the biology. Here are a few examples. 

- **Reinforcement learning** is based on a similar way that animals (such as dogs or [pigeons][3]) can learn [[1][4]]. 
- **Artificial neural networks** are very approximative models of human neural networks. 
- **Genetic algorithms** are roughly based on Darwin's theory of evolution. 
- **Ant colony optimization** algorithms (and, in general, **swarm intelligence**) are based on the way real ants (and, respectively, [biological swarms][1]) behave. 

There are probably other examples that don't come to my mind right now. See also [this question][2].

I had once read that there are cases where AI discoveries have also helped the development of the biology field.

 [1]: https://en.wikipedia.org/wiki/Swarm_behaviour
 [2]: https://ai.stackexchange.com/q/20540/2444
 [3]: https://www.youtube.com/watch?v=QKSvu3mj-14
 [4]: http://incompleteideas.net/book/RLbook2020.pdf