You gotta love evolution.
Japanese people have special tools that let them
get more out of eating sushi than Americans can.
They are probably raised with these utensils from
an early age and each person wields millions of
them. By now, you've probably worked out that I'm not talking about chopsticks.
The tools in question are genes that can break
down some of the complex carbohydrate molecules
in seaweed, one of the main ingredients in sushi.
The genes are wielded by the hordes of bacteria
lurking in the guts of every Japanese person, but
not by those in American intestines. And most
amazingly of all, this genetic cutlery set is a
loan. Some gut bacteria have borrowed their
seaweed-digesting genes from other microbes
living in the coastal oceans. This is the story
of how these genes emigrated from the sea into the bowels of Japanese people.
Within each of our bowels, there are around a
hundred trillion microbes, whose cells outnumber
our own by ten to one. This 'gut microbiome' acts
like an extra organ, helping us to digest
molecules in our food that we couldn't break down
ourselves. These include the large carbohydrate
molecules found in the plants we eat. But marine
algae seaweeds contain special sulphur-rich
carbohydrates that aren't found on land. Breaking
these down is a tough challenge for our
partners-in-digestion. The genes and enzymes that
they normally use aren't up to the task.
<http://blogs.discovermagazine.com/notrocketscience/2010/04/07/gut-bacteria-in-japanese-people-borrowed-sushi-digesting-genes-from-ocean-bacteria/>Link
