Michael Bok
@mikebok.bsky.social
1.1K followers 220 following 42 posts
Biologist at Lund University, Sweden. Interested in the evolution and function of vision in invertebrates. Middling photographer.
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Reposted by Michael Bok
gkafetzis.bsky.social
..with a huge payoff, in gradual steps:
✅Choice of right depth
✅Body Posture
✅Visually - guided locomotion, eventually

7/n
Reposted by Michael Bok
Reposted by Michael Bok
neurofishh.bsky.social
Very excited about our new preprint, led by @gkafetzis.bsky.social /w @mikebok.bsky.social & @denilsson.bsky.social. We suggest that the vertebrate 'duplex' retina emerged from interconnecting two ancient median-eye microcircuits. Say goodbye to the 'simplex' retina - it probably never existed!
Reposted by Michael Bok
gkafetzis.bsky.social
Most bilaterians keep photoreceptor types separate.
But vertebrate eyes are a mash-up:

🪡Ciliary (rods & cones) and
💈Rhabdomeric (ganglion, amacrine, horizontal)
…all packed into a multilayered circuit.

2/n
Reposted by Michael Bok
gkafetzis.bsky.social
👁️The retina — strikingly conserved across vertebrates, but an oddity among bilaterians!

So how did it evolve?

With @mikebok.bsky.social, @neurofishh.bsky.social and @denilsson.bsky.social, we argue that retinal complexity may 𝑝𝑟𝑒𝑑𝑎𝑡𝑒 𝑡ℎ𝑒 𝑒𝑦𝑒 𝑖𝑡𝑠𝑒𝑙𝑓.

www.biorxiv.org/content/10.1...
1/n
a black and white dog is sitting on a couch with its tongue sticking out .
ALT: a black and white dog is sitting on a couch with its tongue sticking out .
media.tenor.com
Reposted by Michael Bok
multipleye-lab.bsky.social
Fresh(ish) from the week at BESSY II @helmholtz.de looking at the changes associated with eye loss in spiders! Not pictured: our valiant night shifters, @mikebok.bsky.social, Karla Lopez Reyes, and Constance Coubris 💪🏼🌃
Three members of the group stand on a bridge over the ring at the BESSY II synchrotron
Reposted by Michael Bok
mikebok.bsky.social
We will peer across a 500 million year chasm of convergent evolution to discover how high resolution camera eyes in cephalopods and polychetes function without the elaborate local circuitry found in the vertebrate retina.
mikebok.bsky.social
Super excited to have received a @hfspo.bsky.social grant with with @neurofishh.bsky.social for our proposal: Eyes inside out: Visual coding without a multilayered retina in squid and worms.
Reposted by Michael Bok
Reposted by Michael Bok
stevehaddock.bsky.social
A fun case of usual-unusual: Most luminescence in the sea is blue-green, but Tomopteris worms emit yellow light.

With Warren Francis, we found a species that emits blue light — unusual but usual. 🦑🧪
link.springer.com/article/10.1007/s00227-016-3028-2
doi.org/10.1002/bio.2671
Three panels: On top is a face on view of a large Tomopteris polychaete, with orange pigment spots along its long anterior antennae. Lower left shows the yellow bioluminescent emission typical of the genus Tomopteris.  Lower right shows the blue bioluminescent emission of a Tomopteris species. This color is typical for marine animals, but atypical for Tomopteris, which is the odd-species-out for luminescent emission spectra. 
Blue-emitting Tomopteris were independently discovered by our lab in the Pacific and by Anaïd Gouveneaux working in Jerôme Mallefet's lab in Belgium. 
Warren determined that the chemical which gives the yellow color seems to be aloe-emodin, but the function of using yellow light rather than blue remains unknown.  See the two manuscripts linked in the main text, and references therein, for more detailed info.
Reposted by Michael Bok
cephwarden.bsky.social
A polychaete worm with tiny googly eyes, drifting in the great blue.
Reposted by Michael Bok
matteosanton.bsky.social
First paper out on this incredible study system! We describe the remarkably different hunting displays used by the broadclub cuttlefish in the wild.

Paper: dx.doi.org/10.1002/ecy....

Stay tuned for more!!

@drmartinjhow.bsky.social @vancedberg.bsky.social @ecologyofvision.bsky.social
Reposted by Michael Bok
nerdychristie.bsky.social
Mantis shrimp can break glass with their powerful punches. Now we know why they don't break their own claws. That and more of the best in @science.org and science in this edition of #ScienceAdviser: www.science.org/content/arti... 🧪
Definitely don’t poke this mantis shrimp, lest it poke back.  Credit: Chris Spain | CC0
mikebok.bsky.social
Did you know some single-cell dinoflagellates have a lens eye? Anders Garm at the University of Copenhagen is recruiting a postdoc to help find out why. Check out the advertisement, below 🧪

candidate.hr-manager.net/ApplicationI...

photo: Franz Neidl
Reposted by Michael Bok
tessmarraiblelabs.bsky.social
An"eye-catching" talk by Mike @mikebok.bsky.social from the Lund Vision group @lundvision.bsky.social at @univie.ac.at @viennabiocenter.bsky.social today, cutting from fan worm eyes to the gollum-like eyes of alciopid worms (see the recent @currentbiology.bsky.social study: doi.org/10.1016/j.cu...)
Reposted by Michael Bok
mosquitolab.bsky.social
Two blue mosquitoes (there are more!). Left, Toxorhynchites (a worldwide genus whose larvae are predators on other aquatic insects including mosquitoes) and right, Sabethes, a South America genus where adults have large patches of scales on their legs for sexual display.
#BlueMonday
#BlueBugs
An adult blue mosquito sitting on a leaf. A blue mosquitoes sites on a white background. It has large and long patches of scales on it's rear legs.
Reposted by Michael Bok
beetzjerome.bsky.social
Just started reading this exciting book edited by @mikebok.bsky.social & Elke Buschbeck. It takes us to a fascinating world on different visual systems featuring evolutionary and behavioral aspects. A must read for everyone interested in #neuroethology & vision.

link.springer.com/book/10.1007...
Distributed Vision
This volume explores the diversity of distributed eyes in nature, comparing optics, neural processing, and behavioral control.
link.springer.com
mikebok.bsky.social
I do not find the chromatic aberration hypotheses from the lens or pupil to be particularly convincing. The chromophore swapping and tiered retina in firefly squid seems to be the best shot at color vision in cephalopods. Perhaps there are more systems like that in other species.
mikebok.bsky.social
I always liked the idea that they use chromatophore pigments as spectral filters for photoreceptors in the skin to detect environment color, but hasn't panned out. I think they are not matching color, but simply evolved chromatophores suited for their habitat and they just adjust contrast patterns.
Reposted by Michael Bok
samjakeengland.bsky.social
I'm very excited to give this talk in January! It's free to attend via zoom if you're interested! :)
britentsoc.bsky.social
Electric Ecology: How Invertebrates Capitalise on Static Electricity
Join us and Dr Sam England for our next Brad Ashby Memorial Lecture
Thursday, January 23, 2025 · 7 - 8:30pm over Zoom
Booking open now: www.eventbrite.co.uk/e/electric-e...