How humans adapt to eating new types of foods

Most people who realize humans can adapt to digesting new types of food, think they know that there are one or two ways for humans to adapt to new food: by having new types of bacteria in our intestines and the other is to evolve news ways of digesting.

However, there are other ways, as we can sometimes pick up new DNA from other species, as well as pick up the required bacteria to properly digest the new foods.

I suppose that most people would never have consider that a virus could ever have a positive impact on our health!


Viruses and Other Gene Transfer Mechanisms
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The Transfer of DNA Across Species Boundaries
Bacteria trade genes more frantically than a pit full of traders on the floor of the Chicago Mercantile Exchange — Lynn Margulis and Dorion Sagan (3)

While recombination moves whole blocks of genetic instructions within a cell, other processes move whole blocks of genetic information from one bacterium to another bacterium of a different kind. In the analogy between genes and written text, this move is a transfer of paragraphs or pages from one library to another
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Sushi may 'transfer genes' to gut
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A traditional Japanese diet could transfer the genes of "sushi-specific" digestive enzymes into the human gut.

This is according to researchers who discovered a substance in marine bacteria that breaks seaweed down into digestible pieces.
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White Blood Cell Chases Bacteria

Here is an excellent video, and at the end it gives a chance to look at more videos that give further glimpses into what is happening at the microscopic level of life.

Complicated chemicals have been found that replicate and evolve!

The abstract Theory of Evolution simply requires a population of entities that:

1. reproduce
2. at least some new entities in some generations differ from their parent(s) in at least one characteristic that affects their ability to reproduce
3. these characteristic(s) are inherited
   

So any system that satisfies the above conditions can evolve. Note that these entities are not required to be considered alive by any definition. Which is why evolution applies from humans to algorithms used in sophisticated database software like PostgreSQL.

Obviously populations that have frequent generations and where there is a huge variation in the new entities, evolve the fastest - this has been observed, for example compare the rate of evolution of primates (such as humans) to that of bacteria.

Now evidence has been found that complicated chemicals called prions (as implicated in Mad Cow Disease) can also evolve:
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"This means that this pattern of Darwinian evolution appears to be universally active.

"In viruses, mutation is linked to changes in nucleic acid sequence that leads to resistance.

"Now, this adaptability has moved one level down- to prions and protein folding - and it's clear that you do not need nucleic acid (DNA or RNA) for the process of evolution."
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