That little speck at the bottom of the frame is a springtail.
It's standing on water and it's about to do something incredible. Ready?
A perfect landing after 14 backflips across a distance of at least 14 body lengths. Incredible,
right? The jumping behavior of springtails is amazing, but it's incredibly understudied and
mostly undescribed. This folder is the total amount of science done describing their jumps,
and it's pretty thin. This isn't because these animals are hard to find,
they're nearly everywhere. It's probably because of how tiny and fast they are.
Here's one from my backyard and my finger for scale. And that was a jump in real time,
it's nearly instantaneous. Going frame by frame you can actually see how impossible they are to
film with a normal camera. This frame is the only one that captured any of the jump. The only thing
you can see is this streak of motion blur that shows the path that it traveled in the 1/60th
of a second this image was being formed. In the next frame the animal is totally gone. So, pretty
much any recording that captures a springtail jump in detail is capturing something new.
Last year on this channel I published some of my initial work describing their jumps,
and off and on over the past year i've been doing more of it and filming them in new ways.
And i've got some really awesome footage to show you. So, first, let's go back to that one that was
jumping off of water. This is where I found it: in a drainage ditch, next to a highway,
near where I live. For a few weeks last spring a semi-aquatic species covered this little pond,
walking on the surface and leaping around between the water and floating plant material.
Here's what it looks like when they launch themselves off the surface.
This is the view at water level of one of them about to jump. You can see the claws at the end
of the leg sticking just below the surface. These claws are hydrophilic and actually stick to the
water giving the springtail's traction for moving around on the surface. The spring-loaded tail,
the furcula, on the other hand resists water and doesn't break the surface tension when it's flung
down. Instead it pulls the water surface down and they seem to push off the indentation they make.
Only the tips of the furcula briefly break the surface while they spring up and off the water.
In every off-water jump I captured, the springtail launches itself forward
at about a 45 degree angle while back flipping. And the backflips are astonishingly fast.
This one, when it takes off, is spinning backwards at a rate of 290 flips per second. It lands face
first, but most of its body repels water and just floats away across the water surface.
I was curious if jumps off of solid ground would look the same for this species.
So, here are the jumps of six individuals off a solid platform. Some jump forward like they
do off water, but some go backwards. Some jump sideways, while others go up and off screen,
more than 86 times their equivalent in body height before spinning back down. As far as I can tell,
this aquatic species seems a lot more coordinated and controlled when they're jumping off water.
Whether they jump off a solid ground or water, it's all powered by a spring-loaded appendage
tucked underneath their bodies called the furcula. Last year, when I filmed them,
it was mostly capturing stuff between three and five thousand frames per second. And that's fast,
but it wasn't fast enough to see exactly what the furcula was doing when it catapults them off the
ground. So, this past winter when more of the soil dwelling springtails emerged in my yard,
my goal was to film them closer and faster than I had before to try to see, as well as I could,
how their jumps are powered. So, here's some of what I got. This jump and the ones that follow
were captured by filming at 10,863 frames per second. Even at this speed there are two points
in the jump when the furcula is moving too fast to see. The first is when it's released from the body
to the ground. And this makes sense. That's the point at which the stored energy of their internal
spring system is released and they're starting their jump. The second, though, is different.
It's the point at which the tips of the furcula lose contact with the ground. The tail seems
to be in tension and, when it's released, it flings back behind the body. To see either of
these points clearer, though, I needed to film faster. This is a sequence captured at 73,510
frames per second. At that speed, the camera I was using would only record a black and white image
that's just 240 pixels high. But that's enough to see everything clearly and unobscured by motion
blur. I don't think it's hyperbole to say no one has ever seen a springtail like this before.
The slap of the furcula against the ground, how it bends at the midpoint where it splits into a fork,
and the final fast backward flick when it loses contact with the ground.
I feel like it's not exactly right to say i'm filming these animals in slow motion.
I'm not using the camera to exaggerate or prolong what they're doing. I'm just trying to see it! I'm
trying to meet these animals at the time scale at which they're behaving and that turns out to
be really really hard. But, I think it's worth it so we can see and appreciate these extraordinary
creatures for what they are. Okay, let me end this video by showing you one more sequence
and it might be the luckiest thing i've ever caught on video. This springtail is stuck on
its back and it's going to use its tail to bounce off the ground and right itself. That's not too
special of a thing and not particularly hard to capture. It spins a bunch of times, i'll speed
up the playback through this part, but amazingly it stays within the razor thin focal plane of the
camera. And, when it comes back down, this is the lucky part, the first thing to catch the ground is
the furcula. When it does, amazingly it bends to absorb the rotational energy of the springtail and
brings it to a full stop. Then, it releases the energy and throws the animal back into the air,
spinning in the opposite direction. So, this clip is a lucky accident that might be showing
us something about the furcula itself acting as a secondary spring during jumps. For now,
that's my update on the springtail research. I'm excited to work more on this project and i'm sure
this won't be the last springtail video you'll see on this channel. Thanks for watching this one!