7
$\begingroup$

As saying "fundamental conflict", I mean something like two (or more) widely accepted results from different areas (or scales) can not exist logically together. In physics, there have been three conflicts1. I wonder if in biology, do we have such conflicts? And how biologists resolved that?

1 One of them is the conflict between Einstein's general relativism and quantum mechanics. String theory, if it is proved to be true, will reconcile this (read more). But it can also be like the controversy of the property of light. Some said it was particle, some said it was wave. Modern physics says it is both.

$\endgroup$
  • 1
    $\begingroup$ Several of them :P $\endgroup$ – WYSIWYG Apr 29 '15 at 8:45
  • 1
    $\begingroup$ i think it is still not settled, whereas brain "computes" using mathematics, e.g. stores and solves equations, or process of vision is some stochastic MIMO black-box, which we represent as equations/math.models $\endgroup$ – aaaaaa Apr 29 '15 at 10:13
  • 1
    $\begingroup$ But i think that googling should put you on right track. I haven't seen any relevant review, unless you consider latest Nature Methods article on p-value $\endgroup$ – aaaaaa Apr 29 '15 at 10:17
  • 1
    $\begingroup$ This immediately came to mind, though it's not the example from different areas that you're looking for. $\endgroup$ – canadianer Apr 29 '15 at 14:32
  • 1
    $\begingroup$ Here is one of them : link.springer.com/article/10.1007%2Fs10539-008-9126-x sharesend.com/xc55e117 - Hendry, Gonzalez - 2008 - Whither adaptation.pdf $\endgroup$ – user15599 May 1 '15 at 18:54
4
$\begingroup$

Peto's Paradox is a great one. This addresses the disconnect in cancer incidence with cell number in an organism. It goes something like this:

Assume current oncogenesis theory to be correct in that mutation acquisition is the rate limiting step in creating a cancer, such that you need ~5 specific mutations in a single cell for that cell to be fully transformed into a cancerous cell. This then being the case, it is so rare that any cell can acquire all necessary mutations that in humans we don't see cancer incidence appreciably increase until the 5th decade of life.

Now, let's assume man has an average weight of 50kg and a blue whale has an average weight of 130000kg, with roughly equivalent lifespans. Assuming average cell weights are the same in both organisms, there are 2500X more cells in a blue whale than a human.

If linear mutation rate is the rate limiting step in cancer then increasing cell numbers is akin to increasing the number of times you flip a coin to try and get heads, which means there is a 2500X greater chance of getting all ~5 necessary mutations in a single blue whale cell than in a single human cell. If human cancer incidence starts to spike at 50 years, this means blue whale cancer incidence should spike after 7 days and blue whales should largely be eliminated by cancers within the first month of life.

Hopefully makes you question a bit what is causing cancer. Make sense?

$\endgroup$
  • 1
    $\begingroup$ I never heard of that. It is interesting. However, it is the number of cell divisions that separate a given cell at the adult age and the zygote that matters and not the number of cells. Also, individuals that develop cancer rarely developed from a "clean" zygote. This greatly reduce your estimation as well. So is there still some kind of Peto's paradox or is it totally negligible? $\endgroup$ – Remi.b Apr 29 '15 at 16:32
  • 1
    $\begingroup$ @Remi.b -- More cells = more cell divisions required in the first place. Whale cells are not orders of magnitude larger than humans, despite being orders of magnitude larger as an organism. Since the vast majority of cells have some turnover, having more could also mean a hire rate of division even if the time it takes is higher. Peto's paradox looks fine (to me), but it does point out that DNA mutations do not always result in cancer. An extra stop-check prior to cell division seems to have a tremendous effect on cancers if you look at Naked Mole Rats. ;-) $\endgroup$ – MCM Apr 29 '15 at 17:01
  • $\begingroup$ Right, MCM is hitting a bit closer to the point. Remi.b when you say that the number of cells division is important, I agree, but once you have created an organism the cells do not stop dividing, they continue to divide and turnover for the rest of your life. And if you are suggesting by an "unclean" zygote, that it already carries something like an inactivating p53 mutation, this is a very special case resulting in serious problems for the organism because every cell in the body carries the mutation, and will oftentimes be embryonic lethal. $\endgroup$ – The Nightman Apr 29 '15 at 17:13
  • $\begingroup$ And I have to address the Naked mole rats because I think this is great evidence to the contrary of the mutation-centric cancer model. Naked Mole Rats have a higher density hyaluronin which may impede metastatsis, and hyperplasias. This is a great example of an evolved strategy to limit oncogenesis during potential reproductive years. And is doing nothing to change cellular mutation rate. $\endgroup$ – The Nightman Apr 29 '15 at 17:17
  • $\begingroup$ this one is something I'm looking for. Thanks for that. $\endgroup$ – Ooker Apr 30 '15 at 8:53
2
$\begingroup$

Could not fit in a comment...

The question very much depend on what you mean by fundamental conflict (to the point that I am surprised to see nobody complaining that the question is primarily-opinion based). My first reaction is to think that there is no such fundamental conflict in biology just because biology is not really a "fundamental science". I am not sure what I mean by fundamental but I hope the comic will help understanding my point!

enter image description here

Of course, it is not true that biology is just applied chemistry (as I would expect the other relations to be wrong as well). Personally, I know nothing about chemistry and in my field of research (theoretical population genetics), we use math, statistics (which is just applied math) and algorithmic (which I guess is just applied math as well). Math is just applied logic by the way.

There are things we don't understand, but I don't think there are many fundamental conflict or paradox. There are many things that we have hypothesis (sometimes vague hypothesis) for it and have no idea how to test them.

$\endgroup$
  • 1
    $\begingroup$ i think question is about experiments that are contradictory, but haven't been refuted. Or contradicting hypotheses, both of which are supported by strong data and peer-reviewed publications. In terms of "fundamentalism", you are right, there is no "wave-or-particle"-type conflicts. Except on high cognitive level (see me comment to OP) $\endgroup$ – aaaaaa Apr 29 '15 at 20:29
  • $\begingroup$ I always love this cartoon since I am in mathematics/engineering $\endgroup$ – dustin Apr 29 '15 at 23:11
  • $\begingroup$ @aandrev. I agree that there might have some cool fundamental looking stuff in neuroscience. It is a field that is in between algorithmic and neuroscience. $\endgroup$ – Remi.b Apr 30 '15 at 2:49
  • $\begingroup$ @dustin Yes, I like this cartoon. I'd appreciate to add philosophers even further to the right side. However, I apologize but engineering is by definition applied knowledge. So I would place engineering at a pretty low level of purity. $\endgroup$ – Remi.b Apr 30 '15 at 2:51
  • $\begingroup$ @Remi.b engineering is just applied physics if you think about it. The cartoon is also ordered in mathematical rigor so it would probably sit between chem and physics. $\endgroup$ – dustin Apr 30 '15 at 3:15

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.