Obviously parents come before offspring.
The earliest form of reproduction is just binary fission - what an amoeba does by splitting itself into two. In it's simplest (origins of life) form this is just a mechanical process of a proto-metabolism (bunch of chemicals) being split into parts that are smaller versions of the "parent", e.g. some proto-cell composed of seashore froth being whipped into smaller versions of itself.
Eventually the division process became asymmetrical with the spawned child being a simpler proto-version of the adult, capable of then independently developing into the adult form. It seems life developed in the oceans before emerging onto land, so the history is probably of multi-cellular fish-precursors reproducing by spawning simpler (conceptually egg-like) versions of themselves, eventually evolving into egg-laying fish, and then egg-laying land-based animals including the dinosaurs from which birds developed.
So, maybe the best answer to "which came first, chicken or egg?" is "fish".
And of course eggs predate chicken, eggs are seriously old technology.
Back to the tongue in cheek: there is something easily tautological that chickens come from eggs. At some point a non-chicken laid an egg, and the first chicken was born from it. This is true regardless of which mutation one decides is "the" mutation that makes for the "first" chicken.
QED it's the egg
Did the proto-chicken lay a chicken egg which hatched the first chicken, or did the proto-chicken lay a proto-chicken egg which hatched the first chicken?
If a chicken egg is an egg that hatches into a chicken, the egg came first.
We know that the first case is correct because an unfertilised egg laid by a chicken is called a chicken egg despite by definition not hatching into a chicken.
Therefore the chicken came first
Or alternatively we can say that the germ line went from 49% chicken to 50% chicken to 51% chicken? Biology is really a continuous state space anyway and trying to push things into categories too hard will break them.
But it looks like phylotypic animal body plans may have originated in cell aggregates before the development of the egg:
https://onlinelibrary.wiley.com/doi/epdf/10.1002/jez.b.21417
Therefore instead of Chicken of Theseus, I propose Chicken of Thesaurus.
Which itself is surely evolved from Chicken of Thesea.
And, consequently, canned tuna.
>"In fact, the study shows that either the principle of embryonic development existed before animals, or multicellular development mechanisms evolved separately in C. perkinsii."
It all boils down to the debate surrounding abiogenesis: the constant egg-chicken (or gamete-organism) loop does not explain how life came to be, emerging from, in principle, no life. It's paradoxical, just like trying to answer "the chicken" or "the egg". Or, as you seem to prefer, "the reptile" or "the egg".
Hindu Mythology: Universe emerged from a "cosmic egg" (Brahmanda).
Greek Mythology: Orphic tradition describes a universe hatching from an egg.
Chinese Mythology: Pangu broke out of a cosmic egg, creating heavens and earth.
Big Bang Theory: Universe began from a dense, hot "singularity," conceptually like a cosmic egg.
Symbolic Parallel: Egg symbolizes unity and potential, akin to the universe's origin.
What's a chicken?
>A vessel to cross the street.
"Ogres are like onions! They have layers, just like onions. You get it? We both have layers"
"Delineation" between these automata is only possible with edges - a membrane, an egg, of sorts.
Id take the credit for it, but lack the ego.
Well I think the original saying could be expanded to something like "Given that chicken birds hatch from chicken eggs, and chicken eggs are layed by chicken birds, how did the cycle get started?"
Or in the case of the article "Given that all egg-layers hatch from eggs and that all eggs are layed by egg-layers how did the cycle get started?"
To answer the former question, we know that a bird can lay mutated eggs, but an egg can hatch into a mutated bird. So a not-quite-chicken layed a chicken egg.
The article deals with the second question.
Returning to your question I guess the answer you are looking for is a watchmaker God? And that if then we continue the analogy the purpose of the universe is to develop into another God?
Without us there wouldn’t be chickens, or chicken eggs.
A miserable little pile of secrets.
As per theory of evolution, current species were created from ancestor species. Since chicken's ancestor species obviously laid eggs. It stands to reason that first chicken came from chicken egg which came from non-chicken!
So, egg came first.
Update: fixed typo
Anyway, the veracity of that legend doesn't matter, but it is here merely to illustrate the idea that perhaps we subconsciously build our roads on lines that chickens won't cross, rather than them being aware of the road?
The upside of this is that Mathematicians get to be scientists, too! The downside is that you also have to let the darn philosophers in ;)
It's almost like there's a reason the common usage is the way it is.
Why have two terms for the same thing?
Mathematical and philosophical work simply aren't the same as scientific work, despite **the non-zero overlap.**
Personally, I find the utility of including all systematic human pursuits as one lineage to be much greater than the utility of cordoning off empirical physical science. The latter is the status quo, often phrased along the lines of "for a long time everyone was silly and wishy-washy, and then science came around in the 1600s." For one thing this silences many great voices from the past, and for another I'd say it's behind the current crises around what exactly constitutes "human" or "social" sciences.
For example: the answer to "what is psychology" is a lot easier to productively answer if we start the search in 400 BCE instead of 1900 CE.
"Silencing voices" is entirely beside the point. We don't need to invalidate all past mathematical or philosophical work by not calling it science. Except, of course, that quite a lot of it is flat wrong.
"Social science" and psychology are actually excellent examples. Their status as science is questioned exactly because their connection to empirical evidence is so tenuous.
To frame the problem we would need to figure out what came first, the scientist or the definition.
This discovery could also shed new light on a long-standing scientific debate concerning 600 million-year-old fossils that resemble embryos, and could challenge certain traditional conceptions of multicellularity.They do know. But it's not a binary phenomenon, and people don't all agree where to place the line.
Edit: folks, there actually is some interesting science here if you can avoid getting hung up on the silly title.
It is likely that the ancestor of all choanoflagellates was already colonial.
The fact that Chromosphaera is also multicellular for the initial part of its life and it also shows differentiation in at least 2 kinds of cells does not imply that it is more closely related to the animals than the choanoflagellates.
Also in some choanoflagellates, differentiation in 2 kinds of cells has been observed and it has been verified that the same genes are involved in multicellularity, both in animals and in choanoflagellates.
See e.g. https://www.biorxiv.org/content/10.1101/452185v1
So this new discovery just pushes back the origin of the mulicellularity of the animal type, from the common ancestor of animals and choanoflagellates to the ancestor of all opisthokonts more closely related to humans than to mushrooms.
(Opisthokonts are a group of living beings composed of animals, fungi and their relatives, which are characterized by cells that swim using one posterior flagellum, like the human sperm cells.)
It is likely that the split between the opisthokonts related to animals and the opisthokonts related to fungi has arisen because the former have remained in marine environments while the latter have adapted to continental environments, so in order to survive desiccation the ancestors of fungi have acquired a cell wall made of chitin that has protected their cells but which has caused the loss of their mobility, leading to the difference in lifestyles, where animals move around finding and eating their food, while the fungal spores are spread passively by wind and then they grow into their food.
(That bit about the opisthokont split with fungus is fascinating, thanks.)
This is a reminder, however, that the questions we ask are very powerful framing devices that can constrain or liberate our thinking.
But if you're on the strict interpretation, the change was so gradual over so many generations it's hard if not impossible to detect. Even when it speciates (becomes unable to produce viable offspring after mating) is hard to tell. There was like likely a long stretch of many generations where sometimes it worked, sometimes it didn't.
TL:DR; How long is a piece of string?
edit: Variation of the same question: Were there radio waves before there radios? Jupiter and thunderstorms produce them, but we had no way of knowing so to us they did not exist.
I'm not sure that is analogous. The chicken/egg question is about at what point we started identifying an egg as being a chicken egg as opposed to being an egg from another animal. In other words, did the first chicken egg come from a chicken (meaning the chicken came first), or from a proto-chicken (meaning the egg came first)?
A closer variation might be: Which came first, the radio broadcast or the radio broadcaster? Before the radio broadcast and radio broadcaster there was radio and people using radio, but they did not reach a wide public audience. At some point the early small-scale experimental radio use turned into broad utilization, but when and which was earlier on the timeline?
You can. But making radio waves does not imply a broadcast. At least not in the traditional sense. I'll grant you that colloquially we have sometimes come to refer to any radio transmission as a broadcast, but that is not the usage here.
> BUT, if you don't know you are making radio waves are you still a broadcaster?
If you didn't know a chicken emerged from an egg, is it still a chicken? My experience with young children who don't yet understand that process would say yes. No doubt there are career radio broadcasters out there who are not familiar with the science of radio.
It's not about not knowing of the existence of something, though. We know the chicken came from an egg. We just don't know what kind of egg it was. Was it a chicken egg or was it a flibberdoodle egg? If it was a chicken egg, how did the flibberdoodle lay a chicken egg? If it was a flibberdoodle egg, how did a chicken come out?