Here at SciShow HQ we have a little food area for the employees – Sometimes there are donuts. Sometimes there are nuts. Sometimes dried mango. But the one thing that never sticks around and is gone as soon as we can buy it is the wonderful, beautiful, noble banana. Unfortunately for us, they may not be around forever. [Intro Music] First, the good: bananas are healthy,
packed with nutrition and energy, they fit in your hand and give nice little
cues when they’re perfectly ripe, and are easy to peel and eat; shocking statistic,
the banana is Wal-mart’s number one selling item.
Not the potato chip, not Coca-Cola, not Fifty Shades of Grey, bananas. They
appear to be so perfect for human consumption that Kirk Cameron attempted
to use them to prove the existence of God. Of course this banana was not created by
God, or really even nature. Bananas, at least the ones that you see at the store, were created by people. Don’t get me
wrong, there are wild banana plants – lots of them – they’re native to South and
Southeast Asia, and there are dozens of species and
thousands of varieties. They’re just not the ones we eat. Some
those species, as you might suspect, have seeds, ’cause that’s what fruits
are, they’re fleshy bodies containing seeds. So you might wonder, why have you never
eaten a banana seed? Well, you have… kinda. In cultivated bananas the
seeds have pretty much stopped existing. If you look closely you can see tiny black specks. Those are all that’s
left, and they’re not fertile seeds. If you
plant them, nothing grows. Today’s bananas are sterile mutants. I’m
not trying to be mean, that’s just the truth. Unless you were alive in the 1960’s (hats off to all those older SciShow viewers out there) every banana you
have ever eaten was pretty much genetically identical. This is a Cavendish, the virtually seedless
variety that we all eat today, but it wasn’t always our banana of choice. Until the
1960s, everyone was eating the same banana, it
was just a different banana – the Gros Michel, a bigger, sweeter fruit
with thicker skin. You might notice that banana flavored things don’t really
taste like bananas. Well they do – they taste like the Gros Michel. The
genetic monotony of the Gros Michel crop was its undoing. A fungicide
resistant pathogen called the Panama disease began
infecting Gros Michel crop. By the time growers understood how
vulnerable their crops were, the Gros Michel variety was all but extinct. The entire banana industry had to be
retooled for the Cavendish. Since they’re seedless, the only way to reproduce them
is to transplant part of the plant stem, and for the last 50 years we’ve been
good with the Cavendish, ’cause it’s more resistant to the Panama
disease. However somewhat terrifyingly a strain of Panama disease that affects
the Cavendish strain that we all eat has been identified. A global monoculture of genetically
identical individuals is a beautiful sight to a pathogen. The fungus only has to figure out how to
infect and destroy a single individual, and suddenly there is no diversity to
stop it, or even slow it down. That’s led to a lot
of scientists worrying about or even predicting the outright demise of the
Cavendish. This wonderful most popular of fruits might
completely cease existence. The good news is we now have a much better
understanding of genetics, epidemics, fungi, and pathology.
Scientists and growers have already taken steps to protect the Cavendish. Some growers are creating genetically
different bananas that might replace the Cavendish crop if it fails, while
scientists are attempting to genetically engineer Cavendish plants with immunity
to Panama disease. Plus we learned a lot from the Gros
Michel debacle. Infected fields are quickly being destroyed and new crops are
grown from pathogen-free lab-grown plant stock. So thanks to the people who work
tirelessly to grow and harvest bananas and bring them to us so that we can offer them inexpensively
to our employees, and thanks to the growers and scientists working
tirelessly to make sure that they don’t go the way of the Gros Michel. Thanks for watching this episode of SciShow, if
you have any questions, comments or suggestions for us, you can find us on
Facebook, Twitter or in the comments below, and if you want to
continue getting smarter this year at SciShow, you can go to YouTube.com/SciShow and subscribe. [banana eating noises] [music]