
Did the chicken come first or is it turtles all the way down? - pseudolus
https://www.quantamagazine.org/puzzle-with-infinite-regress-is-it-turtles-all-the-way-down-20200206/
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folli
"The second is the idea that as we go backward in time, life-forms get simpler
and simpler(...)"

I'm not sure this is a very accepted idea anymore in modern evolutionary
biology. Sure, over massive timescales it holds true (a proteotypic single
cellular organism is less complex than a multicellular, eukaryotic animal),
but the reverse conclusion (the arrow of evolution points towards increasing
complexity) doesn't hold up.

A modern chicken is not more 'complex' (whatever the definition of complexity
is) than its Dinosauria ancestors.

~~~
burnte
It is still accepted on geologic timescales, as you mentioned, and exactly as
the sentence stated, "as you go back in time, life forms get simpler". We
started with lipids and other molecules that then appear to have formed
membranes. Amino acids collected in those membranes, formed longer self-
replicating molecules, and prokaryotic organisms. Eventually you wound up with
incredibly simple, chemical ingesting single cell life, and not long after,
eukaryotic organisms with separate nuclei. This then gave way to multi-
cellular colonies, which then lent itself to cellular specialization in multi-
cellular organisms. Then you start to see highly specialized organisms like
plants and animals. Complexity doesn't mean body parts, it means
specialization within an organism and within a species in the beginning. We
see that clearly. Specialization into new niches and adaptations to changing
ones continues even if complexity does not, presently. However, we still might
see something evolve into a more complex, 5 dimensional, dark matter eating,
electro-plasma brained creature.

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mcculley
As an elementary school student [0], I struggled with the incompatibilities of
evolution and the literal Christian creationist model I was taught. I thought
that "the chicken and the egg" was a question of faith. One who believes that
the Earth was created in seven days believes that the chicken came first, in
whole form, on Day Five. One who uses evolution and natural selection as a
model thinks it most likely that the first animal that could be identified as
a chicken grew from an egg that was a mutation from non-chicken parents.

0: [https://enki.org/2018/07/30/things-i-learned-in-
elementary-s...](https://enki.org/2018/07/30/things-i-learned-in-elementary-
school/)

~~~
Cpoll
> mutation from non-chicken parents

Only tangentially related, but that invokes the Sorites paradox:
[https://en.wikipedia.org/wiki/Sorites_paradox](https://en.wikipedia.org/wiki/Sorites_paradox)

If you follow the thought exercise further, there's other considerations: The
first chicken may not have had any other chickens to mate with.

~~~
nkrisc
If you took a chicken today, and looked at every single one if its direct
ancestors down its lineage for the past billion generations, any single
ancestor would probably be indistinguishable from their own parents, yet the
last ancestor would look nothing like the chicken. It's because the
incremental change with each generation is absolutely tiny, but those changes
are magnified as they accumulate over countless generations.

~~~
lurquer
Chickens have 78 chromosomes.

There is nothing incremental about moving from 76 to 78. Or, from 78 to 80
(turkeys).

~~~
Tagbert
Evolution is a feature of populations, not individuals.

If the proto-chickens had 76 chromosomes, and some had a tendency to have
offspring with 78 chromosomes, there would be some 78 chromosome chickens born
within the population. As long as those chickens bred with each other it would
work. Soon they would become a distinct population of individuals breeding
with each other.

~~~
lurquer
How often do chicken have offspring with an extra pair of chromosomes?

Do you have data on this?

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aaron695
I think it's important to state with almost certainty the first chicken died
without having baby chickens (or laying a chicken egg)

Theirs a fair chance it also just dies without breeding.

I'm not sure I see this discussed much?

It's not a clear way down, that's not how evolution works.

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o_nate
Jim Holt's book "Why Does the World Exist?" is an interesting tour through
different approaches to this topic.

