micronucleus

You can also get the ATiny85 to speak USB and even be flashed via USB via the micronucleus bootloader [2].

This isn't really comparing C and Rust for ATTiny85, it's comparing Arduino flavoured C++ and Rust for ATTiny85 running a micronucleus bootloader.

These cells discard the macronucleus, forming a new one from the new micronucleus.

But eventually, the ciliate mates, or goes through a sort of self-conjugation event, dividing into more than one cell, each of which gets a new micronucleus formed by recombination.

The macronucleus contains numerous copies of DNA from the micronucleus, which could provide a lot of scope for states that are represented in terms of gene activations, allowing behaviours such as described in the article.

The ATTiny85 is incredibly trivial to get code running on in C (and less trivial in Rust, but probably still easier than what this blog post makes it out to be) if you eschew the complexity of Arduino and USB (micronucleus).

Ciliates are very elaborate single-celled organisms, with the unusual feature of having a "macronucleus" in addition to a "micronucleus" that is similar to the single nucleus of other eukaryote cells.

A newly "born" ciliate has a "micronucleus", similar to one of ours, from which it makes multiple copies of its DNA to form a "macronucleus", which does all the work.