Evolving Animats

Evolution of one example animat in the Task 4 environment of Albantakis et al. 2014. In Task 4, the animat must catch blocks of size 3 and 6 and avoid blocks of size 4 and 5.

Generation 0


The animat is initialized at generation 0 without connections between its elements (sensors S1, S2; motors M1, M2; hidden elements A–D).

Due to selective pressure to increase its fitness, at later generations, the animat developed more network connections.

  • Self-loops are indicated by dark circles around the elements.
  • Elements with no connections are grayed-out.



Number of Concepts

At generation 24,576, the animat's network becomes integrated; a feedback loop appears between nodes A, B, and D. At the same time, the number of concepts (intrinsic causal functions) increased.


Albantakis L, Hintze A, Koch C, Adami C, Tononi G. 2014. “Evolution of Integrated Causal Structures in Animats Exposed to Environments of Increasing Complexity.” PLoS computational biology, 10 (12), pp. e1003966.

Visualization: William Mayner