A fascinating look into the work of Sewall Wright, who used guinea pigs to explore Darwin’s theory of evolution. Zachary B. Hancock effectively distills complex processes into comprehensive and lucid writing. This piece will make you think, but it is so entertaining you will also sail through to the end.

There are a lot of ways to build an animal. The biodiversity of our planet is a testament to this. But if you imagine an organism as a fully constructed Lego toy, consider all the ways those individual bricks could be reassembled to build a wholly new thing. The entire range of possible assemblies is vast and yet the living world occupies only a tiny fraction of this design space. Nowhere does there exist a pig with wings, a bird with antlers, or a frog species with six legs.

One reason, first hinted at by Darwin, is that certain assemblies simply work better in their environment than others. These configurations allow organisms to survive and reproduce, passing on their specific Lego blueprint to the next generation. Once an organism has arrived at a structure that does well in its environment, randomly swapping some pieces are more likely to cause harm than further improvement.

More picks on evolution