/sci/ - Science & Math

[Anonymous No.4162845]

How does the theory of evolution explain the identical symmetry of the left and right sides of the body (not including internal organs)? How could this happen by random mutation?

[Anonymous No.4162855]

/thread

[Anonymous No.4162862]

>>4162855
Explain.

[Anonymous No.4162878]

>>4162845
>Evolution.
>Random mutation.

[Anonymous No.4162883]

>>4162845
Because having the left side body different from the right side is a burden.

[Anonymous No.4162886]

>implying a better question wouldn't be why the human body has such a low simmetry

[Anonymous No.4162891]

>>4162845
if you aren't balanced you fall over or limp, in both cases making you susceptible to predators.

[Anonymous No.4162897]

>>4162855
Good job bro.

1. Bodies grow by chemical means. Symmetry spontaneously emerges in many chemical processes when there is no reason for asymmetry.

2. It is an evolutionary advantage to be symmetrical, for mobility, etcetera.

Thread over.

[Anonymous No.4162903]

>>4162845
Segments, look at insects.

[Anonymous No.4162906]

Well, it requires less information to build something that has symmetry.
Symmetrical organisms have far better locomotive success.
Symmetry itself is a common factor in chemical structure, in charge, in physical structure (like leverage and base states).

Symmetry has a particular appeal to human brains, but that doesn't make it suspect or suspicious behavior for the natural world
-- and it is only our natural emotional affinity for symmetry that suggests there is something divine about it.

[Anonymous No.4162908]

[Anonymous No.4162910]

Symmetrical embryos and zygotes are simpler than asymmetrical ones.

[Anonymous No.4162916]

>>4162883
>>4162891
Yeah, but a need doesn't make a mutation magically appear. Also, the mutations for the left and right side would occur at different time periods, making their evolutionary tracks different and would result in a noticeable difference between those features on the left and right side (color, texture, location). How do two identical random mutations happen at the same time and then develop in the same way over millions of years?

[Anonymous No.4162921]

[Anonymous No.4162926]

>>4162916
> Also, the mutations for the left and right side would occur at different time periods

here's your stupid mistake bro

[Anonymous No.4162933]

When you are running away from a predator, what is the most efficient path, straight in the opposite direction or curved to one side?

If you had lopsided legs you'd, A. be bad at running in the first place, and B. Run in a curved path.

Both of which are bad.

Secondly, symmetry is parsimonious, it uses less genetic information. Using less to get more = efficiency. Parsimony seems to pervade the entirety of the natural world, so symmetry only makes sense.

Also, I see your vitruvian man and raise you a toilet design.

[Anonymous No.4162935]

>>4162916

you got to have knowlege of embryogenesis and how tissues with genetically activated genes form bodies in the first place

[Anonymous No.4162941]

[Anonymous No.4162945]

>>4162916
a mutation in the genes that code for legs would affect both legs. Need does not pick a mutation but rather kills off all organisms without mutations that allow the organism to survive in the environment.

Please go take genetics and developmental bio classes.

[Anonymous No.4162954]

>>4162916
Why would you assume the need to have two separate genes/mutations?

[Anonymous No.4162964]

OK guys, then explain the asymmetry found inside the body.

[Anonymous No.4162983]

>>4162964
1. again, parsimony
2. form follows function

[Anonymous No.4162994]

>>4162954
A single mutation can define an assymmetric structure; it would not define two separate assymetric structures.

If you imagine a body developing three legs on a side, and that the genetic coding does not automatically define in symmetry, then you have to expect whatever else develops on the body (legs on the 'other' side) is defined by a separate codon.

[Anonymous No.4163002]

>>4162964
In some cases, small regions of macro-scale asymmetry were advantageous. But organisms are almost always primarily symmetric.

[Anonymous No.4163117]

>>4162964
explain the very small and subtle differences?
We satisfied the major issue over millions of animal examples, now you're going to test us against tiny and subtle examples?

Do you admit that there is justification for common, large-scale symmetry
that doesn't imply external planning or influence?

If so, then may I suggest that there are still influences at smaller scales that can organize into assymmetrical forms?
Wasn't that your presumption in the first place?

[Anonymous No.4163231]

http://www.physorg.com/news95954919.html

[Anonymous No.4163937]

What a stupid premise in that book.
or, rather, a vastly overstated premise and comparison with an overbroad set of animals.

"Lieberman presented his theories of the importance of running to ancestral humans to explain why we’re the only species that voluntarily runs extraordinarily long distances, such as the 26.2 miles in the marathon."

“Why Humans Run: The Biology and Evolution of Marathon Running”

So, it essentially ignore all quadruped migrations, most seasonal bird flight, and the spawning behavior of dozens of kinds of fish.
Wow; he's really set humanity aside from the pack there.
(I think I want to read it just so I can see how he skirts those.)
He could have also said humanity's sweatiness and smell,
loudness and variety of vocalizations, tool use
and habit of breaking 'nature' everywhere he went (making tools or fire)
so upsets other animals that he is forced to run just to find food.