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Hi hackers,

it's obviously not a good thing to eat loads of moldy food. The mycotoxins (such as aflatoxins) seem to damage the liver.

But I can't believe our ancestors always had flawless foodstuff. Or maybe some of the stored reserves got a bit moldy. Shouldn't our body have developed machanisms against those mycotoxins? Or maybe the mold strains on paleo food do not produce such strong poisons? After all, there's no risk in drinking wine, as those yeasts do not produce any toxins.

Any ideas?

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Psst, ethanol is a toxin. – Matt May 29 2012 at 13:05
:D .. I missed the forest for the trees. But after all, I takes a much higher dose of ethanol to cause severe harm. – Thomy May 29 2012 at 17:51

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The worst mycotoxins (aflotoxins, ergot alkaloids, etc) are produced by molds that occur on stored grains and legumes. There hasn't been enough time to evolve resistance - these haven't been a substantial part of the human diet for any more than 10,000 years tops.

Added: Some more answers to your question can be found in this paper http://toxicology.usu.edu/endnote/329c6ba9a2d273760688e0d%26ie.pdf Especially check the subsection headed "There is limited protection from co-evolution".

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Great! Another point against grains and legumes. So it seems that moldy fruit should be less toxic, since humans had more time for adaption? Or is there no difference b/c yeasts have a much faster evolution? – Thomy May 29 2012 at 17:53
Not necessarily. Evolution occurs because some random mutations are net beneficial to the organism that they occur in, at least in the particular circumstances under which they occur. If that organism is able to reproduce better because of them (for instance by not having its seeds (future offspring) eaten) then that mutation is more likely to be retained. It could be case where the mutations (random) just happened to be deadlier to humans. Or (and I suspect this) there is simply more evolutionary pressure to develop toxins in seeds because they will develop into the next generation. – Karen May 29 2012 at 20:49
So seeds that aren't toxic are more likely to be consumed and their genes are removed from the gene pool. More toxic seeds are more likely to survive as the animal eating them either dies out or learns not to eat that junk. Or in the case of humans, subverts the whole situation because once population is high and dense, calories to fend off starvation are more important then caries and gut problems. And then the humans decide it so important to get the calories that they start planting the grain seeds everywhere. – Karen May 29 2012 at 20:54
Anyhow, there isn't as much evolutionary pressure on plants whose leaves are eaten (some, but not as much as with devoured seeds) or whose fruit is eaten. In fact it can be an advantage to the plant to wrap deadly seeds (apple seeds contain cyanide = don't eat too many) in a nice juicy, sweet colorful outside. That tasty fruit attracts an animal who eat it and then poop the seeds (that have evolved seed coats that resist digestion) out somewhere else, leading to the species spreading out from under the root competition of the parent plant. – Karen May 29 2012 at 21:00
But, BUT, BUT! I'm a horticulturist, NOT an evolutionary biologist, so you may want to do some exploring of this by reading experts like Dawkins - 'The Selfish Gene' etc. – Karen May 29 2012 at 21:02
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Our ancestors were probably in the habit of eating their food fresh, not storing it. Especially if they were traveling light. So I assume the food wouldn't have had a chance to get moldy. If it did, I bet they'd throw it out like we did, or eat around it.

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