That's a big deal: "De novo origins of multicellularity in response to predation" by Herron et al. 2022

"We subjected outcrossed populations of the unicellular green alga Chlamydomonas reinhardtii to selection by the filter-feeding predator Paramecium tetraurelia. Two of five experimental populations evolved multicellular structures not observed in unselected control populations within ~750 asexual generations"

HT @mads100tist @mhendricks

"Structured cerebellar connectivity supports resilient pattern separation" Nguyen, Thomas et al. in @darbly's lab

Spectacular work based on connectomic reconstruction from nanometre-resolution volume electron microscopy and computational modelling that contributes novel findings in cerebellar microcircuitry:

"both the input and output layers of the circuit exhibit redundant and selective connectivity motifs, which contrast with prevailing models. Numerical simulations suggest that these redundant, non-random connectivity motifs increase the resilience to noise at a negligible cost to the overall encoding capacity. This work reveals how neuronal network structure can support a trade-off between encoding capacity and redundancy, unveiling principles of biological network architecture with implications for the design of artificial neural networks."

“Exercise increases information content and affects long-term stability of hippocampal place codes” in mice. But the implications are tantalising.

Rechavi et al. 2022

This hard finding stands out: runners showed increased neurogenesis in their hippocampus.

“To assess the levels of hippocampal neurogenesis, we injected mice with Bromodeoxyuridine (BrdU), a marker for proliferating cells. In accordance with previous results (van Praag et al., 1999b), we found a higher number of BrdU-positive cells and increased labeling density of doublecortin (DCX), a protein transiently expressed in newborn neurons, in the DG of runners (Figures 1B–1D). This increase in adult neurogenesis indicates that physical activity affected the physiology of hippocampal circuits in our experiments.”

The distribution map of the hoverfly Eristalis pertinax may be telling a story about failed clean water regulations:

“Eristalis pertinax is a European hoverfly. Like Eristalis tenax, the larva of E. pertinax is a rat-tailed maggot and lives in drainage ditches, pools around manure piles, sewage, and similar places containing water badly polluted with organic matter.”

Caveats: sampling bias, and unknown distribution prior to modern waterways pollution.

Interesting cache bug in the Mastodon app: @Gargron The left image is not the image of this screenshot’ed toot, but when clicked it opens the proper image. Closing it goes back to the wrong one. That “wrong” image is the last one I uploaded in a toot of mine, but note I did so from the website, not the app.

Neuro-evo conference at HHMI Janelia on May 15-18, 2023. Join us for the third edition!

Application deadline: Jan 27 (11:59 p.m. EST) 2023.

Apply here:

"Historically, with the study of the most convenient animal models —from the giant axon of the squid and the lobster's stomatogastric circuits to Aplysia's synapses and C. elegans' circuits — neuroscientists revealed some of the operating principles of the nervous system, which were then found to apply broadly across phyla. The third instalment of this meeting will once again bring together neuroscientists working on a broad diversity of animal models in an effort to compare circuits across phyla as a means to crack their function."

Wow, interactive 3D scans of animals and plants:

The paper: "Bio-photogrammetry: digitally archiving coloured 3D morphology data of creatures and associated challenges" by Yuichi Kano

See for example this one of an Asian Giant Hornet, Vespa mandarinia (click and drag with the mouse)

HT: Rainmaker1973

My favourite grasshopper photo moment: moulting sequence. 

An unusual observation in the wild: a pale-looking large grasshopper nymph, immobile, that started moulting with undulating, rhythmic motions. The head cuticle slowly detached as the new body propelled forward–giving it the appearance of having two heads. Half way through, a yellowjacket wasp attacked!

The wasp munched on the soft, unexpanded wings while the grasshopper helplessly continued its slow moulting procedure into its adult form. Left alive but not unscathed.

Egyptian bird grasshoper, Anacridium aegyptium, on a lemon tree in Hvar island, Croatia

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Ever looked at a grasshopper up close?

When approached, grasshoppers either jump and fly away–if I'm too fast–or remain very still, as if whispering a mantra "I am not here, you haven't seen me". Except this only works when the camouflage pattern matches their background. Not the case here!

Chorthippus apricarius

Not a wasp, but beautiful nonetheless! Memoirs of a summer by the sea.

Scarce swallowtail butterfly (Iphiclides podalirius) on a saltwater-sprinkled bush, Croatia.

On dead ants ... their mandibles and bodies can endure a lot. Here is another unidentified dead ant, mandibles clasping onto the leg of a masked bee (who knew ants and bees battle?). The dead ant served as a natural marker for this one particular bee, which I was able to recognize over the course of multiple days on the same mint flowers.

Hylaeus modestus (a masked bee) plus unknown ant, on mint flowers

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And differences in size are also the norm. Not only among ant castes of the same species, but particularly among different species! Here we see a desert ant (a relatively large ant for Europe) carrying a tiny dead one still clasping its mandibles on its antenna, marching on unfazed at full speed among the pebbles of a Croatian beach.

Cataglyphis nodus (large ant) and an unidentified tiny dead ant attached to its right antenna.

Differences between males and females are the norm among ants. This male ant is tiny at 3 millimetres long. For the longest time, I had not the foggiest idea what this was other than a wasp-like animal. Thanks to the iNaturalist community it was identified.

Male ants are a rare sight, emerging only at the right season and only for a brief period of time. It is said that most die shortly after mating.

Stigmatomma sp, possibly S. denticulatum.

Have you ever seen ants mating? 

Right on the windshield of our car, this past summer. The male is indeed tiny. Crummy photo, was as spontaneous and unplanned as it gets: at a traffic light!

Lasius sp. (likely but unconfirmed) There are more photos at the entry.

Need a good laugh? 

Do you keep hearing about machine learning taking over the world "soon anytime now"?

This entry of mine from 2009 has been labelled, presumably automatically, as "mature content". I kind of see why–not quite an adversarial attack, but yes quite the failure of excessive generalization.

It's a most innocent photograph: that of my favourite lunch, back from when I was at INI Zurich: mozzarella with cherry tomatoes, olive oil, salt, and ... bread.

For all electron microscopists out there:

"Crosshair, semi-automated targeting for electron microscopy with a motorised ultramicrotome"

Kimberly Meechan et al. 2022 @eLife from Yannick Schwab's lab at EMBL in collaboration with The Crick institute.

Presents a new method for reliably and "selectively targeting small regions of interest in a resin block by trimming with an ultramicrotome", powered by "user-friendly software to convert X-ray images of resin-embedded samples into angles and cutting depths for the ultramicrotome."

Reviewed by three outstanding electron microscopists: Christel Genaud, Song Pang, and Michaela Wilsch-Bräuninger.

Want to study bumblebees in the Arctic? The impact of global warming on pollinators? There's an open PhD position in Richard Gill's lab at in London

The PhD ad is a PDF:

"Our knowledge of how interaction networks, such as plant-pollinator relationships, are being
affected by climate change remains in its infancy. This is primarily due to us having a limited
understanding of the underlying mechanisms determining how plant and pollinator
populations respond to climatic variation."

"This project will study an Arctic plant-pollinator community located in Lapland (Sweden) by
taking advantage of a unique phenology transect spanning an elevational gradient."

Have you ever encountered a wasp about 4 to 5 cm long? At the risk of anthropomorphising, as it raises into the air, hovering near you, observing you, one feels the presence of a being so confident in its position at the top of the food chain, that it judges you, it evaluates you as a non-risk (perhaps unwisely), and, after a brief few moments, moves on with its day–to find a large spider to sting and stash away in its offspring's pantry. It's entirely harmless to us, and the adults drink nectar from flowers. It's enemies are, I'm sure, other parasitoid wasps.

Cryptocheilus annulatus is one such wasp. From Hvar island, Croatia.

Spam also coming to . Or this is someone spoofing brand accounts in their own instance, to mock them. Just read the screenshots of the toots.

Know anything about this, @freemo @trinsec ?

For neuroscientists attending : don’t miss the poster by Mitya Chklovskii’s group describing the completion status of the whole brain of the fairy wasp , of expected completion early in 2022. Find the poster tomorrow Monday morning, number 328.16 / YY35.

Mitya kindly shared the poster image publicly elsewhere.

This tiny is famous for being the size of a large paramecium (a unicellular organism) and for enucleating the vast majority of its central neurons while pupating. The adult has less that 10,000 neurons in its central brain yet it isn’t missing any organ or body part. See the paper that jumpstarted this effort:

Polilov AA. The smallest insects evolve anucleate neurons. Arthropod structure & development. 2012 Jan 1;41(1):29-34.

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