I was at a Knapsack Patterns event in Minneapolis recently. Lou Manning from ADP made a throwaway comment about how all AI applications will eventually become shadcn UIs.
That might be true.
Evolutionary biology has a concept called carcinization. Crustaceans that aren’t crabs will - independently - evolve into crab-like forms. They do it across lineages, and it’s happened multiple times through history.
Different species. Different environments. Same solution.
Crabs, as it turns out, are what you get when you optimize hard enough for a similar set of pressures.
You might make the same observation about the application landscape. The same component libraries. Same sidebar navigation. Chat interface with an input field at the bottom. Muted palette, rounded corners, and empty states with friendly illustrations.
Nobody is copying anybody.
It’s a reaction to the same constraints. Foundation models producing the same outputs. And now we’re optimizing for the same LLM coding workflows. That creates a consistent pressure to ship fast, test cheap, and iterate immediately.
Same environment. Same selection pressures.
Same crab.
When everyone’s solving for the same things - speed, cost, LLM-friendliness - convergence isn’t a failure of imagination. It’s the logical outcome. And AI can make that convergence happen at speed.
Carcinization is inevitable...if the selection pressures stay the same.
Crabs aren’t destiny. Crabs are what evolution produces to answer a specific question. If the question changes, the answer will too.
Teams building things that actually look different aren’t ignoring the constraints. But they’re adding at least one more - the need for something to be good. Not just fast and functional. And not just a matter of taste.
Good that requires someone to have made a decision about what good means.
AI can’t optimize that. It’s a human call.
Speed is table stakes. Cost is...if not free then converging to the point of consistency. The scarcity is wanting something specific that pushes against the path of least resistance.
I wrote a piece last year about how AI changes the creative equation. Fast is free. Cheap is everywhere. So the only real differentiator left is good.
This is what that looks like in practice.
Yes, early AI adoption will make teams stand out. But AI will make fine effortless. The true differentiator is something ingenious, or newly imagined.
Convergent evolution is real. It happens anyway. AI means it’s coming for every product category, every interface pattern, every design system. And coming fast.
Time to decide whether you want to be a crab.
Further reading:
Hamers, L. Why Do Animals Keep Evolving into Crabs? Scientific American, Jun 2023.
Rizal, K. Tyranny of Smoothness in the Age of Generative AI. AI Advances, Jan 2026.
Martignetti, T. AI is replacing creativity with ‘average’. Fast Company, Apr 2026.
Article photo by Mackenzie Cruz on Unsplash.