Science and Nature are the canonical exaggerators when it comes to headlines. Whole genome, whole mitochondria, complete, total, you name it, there is (nearly?) always an invisible asterisk at the end. When these words are use then Materials and Methods tell you what actually happened.

What's completely crazy in this research is the ability to thin-section fly brains. Thousands and thousands of slices _of a fly brain_, good old physical science at the heart, crowd-sourced to connect the dots (though I'm not positive that's the case in this paper). The open-hardware imaging tools used in some studies like this are also super cool- https://openspim.org/.

This is an electron microscopy based study, not light microscopy (i.e. SPIM or open-spim). Or did you mean something else?

larvae behave, they learn, they forage, they do have a brain.

Do they learn? What behaviors make a fruit fly larva more intelligent than a jellyfish?

Well granted they're solving quadratic equations, but neither are the adults.

For instance, if you expose larvae a rewarding stimulus like sugar along with an odour, they will later be attracted to that odour. That is by definition learning, simple learning, but we have to start somewhere i guess.

Interestingly there is some evidence that the memory lasts through to the adult stage, despite the fact that a lot of the brain is actually rewired during pupation.

Interesting, with the caveat that the odor/reward experiment was performed on larvae at a development stage with 10,000 neurons, not 3,000.