4 ms·
and from another post on the front page right now https://news.ycombinator.com/item?id=49735541 https://news.ycombinator.com/item?id=49735541 : "Nervous system
by trhway 7d ago
and from another post on the front page right now https://news.ycombinator.com/item?id=49735541 https://news.ycombinator.com/item?id=49735541 :
"Nervous systems are typically defined as networks of neurons that communicate across synapses. But Burkhardt’s lab found something unique in ctenophores: Beneath the animal’s outer surface is a nerve net (pink mesh in this 3D reconstruction) whose neurons are connected by continuous cytoplasm — but with no synapses between them. “I don’t think any other animal has a nervous system like that,” Burkhardt said. Because ctenophores are one of the earliest branches of the animal family tree, the finding indicates that evolution may have crafted nervous systems twice: in ctenophores, and separately in jellyfish and all other animals."
- ozim 7d agoFunny thing when reading that is as a human I read „crafted nervous system twice” like it would be done over a week or two. We fail to imagine how much time takes to „craft a nervous system”. Super scary how small are we in big scheme of things.
- stymaar 7d agoI think the fact that the sentence says we share the nervous system with jellyfish gives a good indication of that.
- cmrx64 7d agohttps://learn.genetics.utah.edu/content/senses/eye/ https://learn.genetics.utah.edu/content/senses/eye/ at one point I learned that it would only take a few hundred thousand years to evolve an eye, and time felt much deeper.