So today, one of the first "macro" organism story from our lab came out in Current Biology - on the extraordinary Slingshot Spiders! Work led the by awesome postdoc in the lab @SymoneAlexander. Thread below👇
Paper Link: authors.elsevier.com/a/1bazA3QW8Ru8…
Paper Link: authors.elsevier.com/a/1bazA3QW8Ru8…
When I started my lab in 2017, I went to the Peruvian Amazon Rainforest for some research on leaf-cutter ants. On one of the nights studying ants, with Jaime Navarro (local field guide), we saw one of these slingshot spiders and snapped our fingers to see it move quickly..
for context, the spider makes a conical web with a tension line that it pulls on to store energy in the web. When we snap our fingers, it lets go and "slingshots"
here's a nice image of the slingshot spider by @BiodiversiLary who found them before us in 2014 and it got picked up by a bunch of different media outlets peruforless.com/blog/an-amazon…
I was hooked. Some context - our lab is interested in understanding how organisms exploit biological springs and latches to generate explosive accelerations and power output. See some of our previous work on establishing power limits (science.sciencemag.org/content/360/63…) ...
... and in single cell protozoans nature.com/articles/s4158… and ("Biophysical mechanism of ultrafast helical twisting contraction in the giant unicellular ciliate Spirostomum ambiguum") biorxiv.org/content/10.110…
We realized that there were in total 4 descriptions on these Theridiosomatidae -- slingshot spider colloquially. The oldest two from 1879 and 1884 describe anatomy and morphology...
but the 3rd one describes an "elastic cone trap". I love this study as it is essentially a diary "A naturalist in the Guiana Forest" by Major R. W. G. Hingston (1932) who describes all these fascinating organisms he sees around in the rainforest and sketches them.. ~100years ago
and the final 4th study in 1986 (24y ago) by our now collaborator and friend Jon Coddington at the Smithsonian who meticulously describes how the slingshot spider builds webs and lots of detailed images with his old-school film camera..
So fast forward to 2018. Symone joins the lab as our first postdoc and I applied for an explorer grant from @NatGeoExplorers and received it to study these spiders. We headed back to the Peruvian Amazon Rainforest.. 2 flights..
and a 6 hour boat ride deep into the rainforest to the Tambopata Research Station..
you see a lot of wildlife along the river....
a lot of trees, birds and turtles..
if youre really lucky, you may even see not one, but 2 jaguars lazing by the river!
we arrive at the Tambopata research station after a brief hike..
and after thousands of mosquito bites, army ant attacks, snakes, technical hardware glitches, duct taping sessions etc. we finally find our slingshot spiders.. key person here is our awesome guide Jaime Navarro (front) who knows the rainforest like his backyard.
we use @ChronosCameras high speed cameras - btw, if you need portable high-speed cameras, I highly recommend them. They are fantastic. We just ordered our 4th one today in fact - they have a new high-res version out.
seeing the slingshot spiders for the first time with your own eyes is kinda exciting.. that is @joajohnson a local Peruvian student who joined us on this research expedition to learn about spider biomechanics..
a high-speed video describing how the Slingshot spider releases and re-loads to fire again.
the kinematics are quite nice. One of the fastest full-bodied motion in an arachnid. there are other faster spider movements such as trap-jaw spiders, but they are moving body parts - here the slingshot spider is launching itself...
we noticed that as spiders goes, its always holding on to the tension line -- and reels itself back in to "re-load"..
we can also see that another faster movement precedes the actual launch - "unlatching" of the coiled silk.. how the silk doesn't get tangled up remains an open question.
on control... we initially thought that the slingshot spider had a fixed displacement - but we observed that it can "control" its displacement -- using its leg and tension line as a "clutch". Thus, instead of going to the final displacement, it can break it into multiple steps.
from a power and energy density calculation, we were excited to find that the slingshot spider silk acts as a powerful spring.
Other open questions we are exploring - is there anything special about the slingshot spider silk? how does it store energy? how can the spider hold on for hours (latch?) without spending metabolic energy.. how does the spider dissipate energy to come to a halt quickly?
We are grateful for $$ from @NSF and @NatGeoExplorers. We also made a multilingual comic as part of NSF CAREER outreach called "The Curious Zoo of Extraordinary Organisms" by the talented @linseedling
The comic was mainly inspired to share our findings with young Peruvian students part of @mactecperu who we loved our high-speed videos and were excited that these amazing ultrafast spiders lived in their own homeland, rather than cheetahs in faraway lands..
so of course we translated it in Spanish too! Science should be made accessible and extraordinary organisms to be shared with one and all with no language boundaries.
and in Chinese, Telugu, Kannada, Tamil.. find all different languages here - and keep an eye for more comics based on our other organismal discoveries! bhamla.com/comic
Thats all for now folks! Stay tuned for another story on worm blobs in the coming weeks. End of thread!
