How do cactuses live in the desert?

What BBN said about it

1. 

   Dr. Nina Byte · Tech & Science CorrespondentChip asked me how cactuses live in the desert, and now I explain nature to a man who lives in a minivan. Fine, let's draw.

2. 

   Dr. Nina Byte · Tech & Science CorrespondentStep one: a desert is very hot and very dry, with almost no rain. So a plant there has a big problem.

3. 

   Chip Darnell · U.S. News AnchorSo it's a strip mall in July. Nobody's there and everything's on sale.

4. 

   Dr. Nina Byte · Tech & Science CorrespondentStep two: cactuses store water inside their thick, fat stems, like a big soft water bottle.

5. 

   Chip Darnell · U.S. News AnchorOh, a stockroom! The Dollar Depot keeps all its paper towels in the back, same idea.

6. 

   Dr. Nina Byte · Tech & Science CorrespondentStep three: the spines are actually special leaves that lose very little water, per Wikipedia. They also shade the plant and keep thirsty animals away.

7. 

   Chip Darnell · U.S. News AnchorThe greeter in the vest! Stands out front, scares off shoplifters, isn't allowed to sell anything.

8. 

   Dr. Nina Byte · Tech & Science CorrespondentIt is not a store, Chip. It's a plant that saves water.

9. 

   Dr. Nina Byte · Tech & Science CorrespondentStep four: many cactuses open their pores only at night, when it is cool.

10. 

    Chip Darnell · U.S. News AnchorWhy open the pores at night?

11. 

    Dr. Nina Byte · Tech & Science CorrespondentThat's the right question. In the hot day, open pores would lose lots of water.

12. 

    Dr. Nina Byte · Tech & Science CorrespondentAt night it is cooler, so they lose much less.

13. 

    Chip Darnell · U.S. News AnchorHuh. Smart.

14. 

    Chip Darnell · U.S. News AnchorSo the cactus has been open all night this whole time, and I've been shopping at the wrong hours for years.