most of us see gigantic insects and politely head in the other direction other more adventurous
types like behavioral neuroscientist and national geographic explorer werner bingman
are apt to crawl around the costa rica rainforest in the dark trying to catch huge whip spiders
we're looking for whip spiders tonight because they come back each night
faithfully to the same little refuge site in this large tree that you've seen a little bit of
they have a remarkable navigational ability werner is running an experiment to better
understand how these whip spiders navigate but first he needs to catch them if you don't
get it they usually disappear into the tree crevices and that animal is lost for the night
quick profits on whip spiders while there are over 150 species of whip spiders
they actually aren't spiders at all just a close relative in the same class of species arachnida
arachnids typically have eight legs however in some species like the whip spider two of the legs
have evolved to perform sensory functions these whip-like appendages called antenna form legs
are long and thin whip spiders also have pincher-like appendages which they tend to
use when scientists try to catch them they're very aggressive they can draw blood and you
gotta tough that once you have the animal you're not gonna drop it just because it's pinching it
i'm gonna take this animal right now and we're going to put this radio transmitter on
we're going to take it about 10 meters away to a place it's never been to before
and see how successful it is navigating back to the tree where we found it you could generally
see them progressively moving closer to the home tree over a series of days these temporary radio
transmitters broadcast location data and will fall off when the whip spider sheds its exoskeleton
well guys if you think there's any doubt that they don't come back with the transmitters here's a guy
that was away 10 meters away and he's pretty much at exactly the same spot that we saw it
and we captured it so i think it's important to note that not only this animal get back to
the home tree it's actually in almost the exact spot where we found it it becomes reminiscent of
the kinds of things that homing pigeons do and sea turtles do what sensory information are they using
are they smelling their way back are they seeing their way back or they're hearing their way back
so for some of the animals that we've captured we're going to cover the tips of their antenna
formed legs with nail polish the temporary nail polish blocks the sensory abilities of
the antenna form this aids in the process of elimination helping burner to gauge the extent
that whip spiders rely on their antenna form their eight eyes or something else for navigation
so do the spiders with painted nails make it home
and the question is do you get back they can't nope it implies that smell and touch information
it's crucial for these animals to figure out how they're going to get their way back home
it's really really exciting to look at how the true kind of navigational system can evolve
with a relatively simple nervous system that these guys have
do
you