Arthropod head problem

[tempaway12644]

I read about this somewhere recently and now I remember - it was "User: Junnn11" on the front page of HN a few weeks ago for their arthropod illustrations (see https://news.ycombinator.com/item?id=35630423 )

Arthropod Head Problem is a really good name for a band

[mjewkes]

Worth checking out the talk page. Looks like this whole article is out of date and that much of the problem is resolved.

[sjducb]

The article doesn't mention phylogenetic evidence at all. That makes me think that this issue may be completely resolved/rendered irrelevant by more recent phylogenies.

[xipho]

While not exactly related a significant contribution has recently been published- https://pubmed.ncbi.nlm.nih.gov/37094905/ in a journal. Tools like this help tease out what things "really" are, as they give a hypothetical context (as opposed to claiming one-true-truth) to help one think about things. Evolution has repeatedly converged on what people would say are the "same" thing many times, this is well understood. Deeply understanding the vastness of biologically diversity, as others have alluded to in the comments, is still relegated to such a tiny minority of human minds that finding a common language to express the nuances discovered with the rest of humanity remains a challenge.

[efitz]

I don’t see how humanity can go on without a solution to the arthropod head problem. The taxonomy might not be correct!

[NoZebra120vClip]

Wow, my eyes fully glazed over trying to just skim that article. Wikipedia has a rule about not over-using jargon, especially in highly technical articles. It looks like some expert attention is needed there to tone that down and translate all that to common English.

[happytoexplain]

I mean, there is only so much you can simplify on some topics, and this is a really specific topic. Making every domain-specific term a hyperlink is about as good as you can hope to get sometimes.

[pvaldes]

In short, animal bodies can be constructed either as a chain of repeated basic structures called segments or otherwise. We could think for example in an earthworm and a jellyfish.

All segmented animals can be represented as a list of ordered segments. Different lists can have different lengths, but the number of elements inside each type of animal is very stable. We are segmented animals also.

An hypothetical animal with five segments in its body plan, would be represented as:

'(1 2 3 4 5)

Each element in (cdr '(1 2 3 4 5)) has the ability to grow a couple of structures called appendix. The first segment will bear another special type of sensors designed to detect light, the eyes. Animals use chemical gradients to modulate the appendix separately and turn them into everything that will need, in the right place.

The concept of chemical gradients is not difficult to understand. Drop some chemical in the first segment and let it to diffuse towards the end of the chain. The first part will receive much more chemicals than the tail, activating different genes. Our embryo now looks like this:

'(head torax abdomen)

Rinse and repeat for each element, nesting lists. This very smart process is all that we need to make an animal while guaranteeing that our embryo will never develop a couple of ears in the legs [1].

[1](... Unless is an arthropod, because each type of animals have their own ways to solve the problems)

[andai]

I wanted to redirect you to the Simple English version, but there is only Esperanto...

[tedunangst]

The whole article reads like it was paraphrased by somebody who doesn't actually know anything about the subject.

[bigbillheck]

I'm not a biologist but it seemed fine to me.

[ftxbro]

weird I put this one last month https://news.ycombinator.com/item?id=35635187

[andai]

Yeah, sometimes stuff will get reposted like 5 times in a row before anyone notices it.