Spider Balloons

(SFX: the end of Charlotte's Web: spiders leaving)

AT THE END OF CHARLOTTE'S WEB, BY EB WHITE, A PACK OF BABY
SPIDERS TRAVEL OFF INTO THE WORLD. 

Suter: "The spider Charlotte has had her kids and the kids go out to the top of a fence post
and they put a little bit of silk out of their rear end, the silk goes off still attached tot eh
spider and pulls up into the air a little bit, pretty soon, the spider lets go of the top of the
fence post and drifts off into the breeze, being pulled along by this little strand of silk.
That's called ballooning" 

ROBERT SUTER IS A BIOLOGIST AT VASSAR COLLEGE WHO'S STUDIED THIS
PHENOMENON.  IT ONLY WORKS FOR VERY SMALL SPIDERS, BUT ALMOST
ALL BABY SPIDERS MAKE USE OF THE TECHNIQUE TO SPREAD OUT INTO
NEW TERRITORY AFTER THEY'RE BORN.  IT'S A LOT LIKE
PARACHUTING--EXCEPT INSTEAD OF A CHUTE IT'S MORE LIKE DRAGGING
A ROPE.

Suter: "You could actually slow yourself down by having a long rope behind you, but it
wouldn't slow you down enough and you'd crash into the ground pretty hard."

BUT THAT'S THE ADVANTAGE OF BEING SMALL--THE SPIDER WEIGHS SO
LITTLE THAT THE AIR FRICTION FROM EVEN THE LITTLE BIT OF STRING
CAN KEEP THE SPIDER ALOFT.  SUTER PUT SOME SPIDERS INTO A WIND
TUNNEL TO EXAMINE THE FLOATING SPIDERS MORE CLOSELY. HE FOUND
THAT THE SPIDERS CONTROL THE DIRECTION IN WHICH IT MOVES.  

Suter: "If you're that small, the position of your legs and the position of your body. .
.makes a different in terms of how much wind resistance you have.  So these spiders can
do some controlling.  If they want to go up faster, they can spread their legs out, and if
they want to go up more slowly they can bunch their legs to themselves. . .  They can spin
around, they can do all kinds of things."

WHICH MEANS SPIDERS ARE DOING THINGS A LOT LIKE WHAT WE SEE
EXPERIENCED PARACHUTISTS DO.

Suter:"I don't think spiders actually do this recreationally."