Exciting work led by Giulia Zancolli on the venomless Uloboridae spiders. They lost their venom glands and venom injecting duct, but wrap their prey in toxic digestive fluids.
The paper: https://bmcbiol.biomedcentral.com/articles/10.1186/s12915-025-02248-1
The press release (in 🇫🇷) https://www.unil.ch/news/1749727639234 #Venom #Spiders #EvoDevo #MolecularEvolution
Beyond venomous fangs: Uloboridae spiders have lost their venom but not their toxicity - BMC Biology

Background Venom, one of nature’s most potent secretions, has played a crucial role in the evolutionary success of many animal groups, including spiders. However, Uloboridae spiders appear to lack venom and capture their prey, unlike venomous spiders, by extensive silk-wrapping and regurgitation of digestive fluids onto the entire prey package. A prevailing hypothesis posits that toxins may have been reallocated from the venom to alternative secretions, like silk or digestive fluids. Yet, whether uloborids have retained venom toxins and the mechanisms underlying prey immobilisation remain unresolved. Here, we employed a multi-disciplinary approach to assess the absence of venom glands in Uloborus plumipes, toxin gene expression and toxicity of digestive proteins. Results Our findings confirm that U. plumipes lacks a venom apparatus, while neurotoxin-like transcripts were highly expressed in the digestive system. Midgut extract had comparable toxicity levels to that of the venomous Parasteatoda tepidariorum. However, no inhibitory effects on sodium nor potassium channels were observed, indicating a different toxic mechanism. Conclusions These findings support the hypothesis that Uloboridae spiders have lost their venom apparatus while retaining toxin-like genes. The potent toxicity of their digestive fluids, a trait conserved across spiders, likely compensate for the absence of venom, ensuring effective prey immobilisation and digestion.

BioMed Central
Nice highlight of our recent work on the evolution of venom production in marine predatory snails
https://www.nature.com/articles/s41559-025-02763-y
#EvoDevo #MolecularEvolution #Venom
Snail venom glands - Nature Ecology & Evolution

Nature
You can still apply: Postdoc job opportunity! We're looking for early career researcher in evolutionary genomics to study the relation between intra-specific gene expression variability, polymorphism, and macro-evolutionary rates. We have all of the data in 3 fishes and amphioxus, just waiting for your expertise and enthusiasm!
https://tinyurl.com/3aewk286
#EvoDevo #MolecularEvolution #bioinformatics #PopulationGenomics #RNAseq #PostDoc
Postdoc job opportunity! We're looking for early career researcher in evolutionary genomics to study the relation between intra-specific gene expression variability, polymorphism, and macro-evolutionary rates. We have all of the data in 3 fishes and amphioxus, just waiting for your expertise and enthusiasm!
https://tinyurl.com/3aewk286
#EvoDevo #MolecularEvolution #bioinformatics #PopulationGenomics #RNAseq #PostDoc
Nice RNAseq atlas of small but important crustacean Daphnia pulex, and study of "selection operating on genes expressed in different tissues" https://www.biorxiv.org/content/10.1101/2025.05.01.651673v1 #EvoDevo #MolecularEvolution #RNAseq #Daphnia #Crustacean
Great to see this out in society journal @molbioevol @officialSMBE!
Cone snails are venomous 🐚🍽️🐟 and have evolved from non venomous marine snails. We show how their venom gland evolved from homologous glands, and how this affected the evolution of their digestive system.
https://doi.org/10.1093/molbev/msaf095 #MolecularEvolution #EvoDevo #Venom
This is the best explanation I've ever seen for lungfish genome sizes
https://xkcd.com/3064/
#XKCD #Genomes #MolecularEvolution #lungfish
Lungfish

xkcd
Ah now for something lighter: a horseshoe crab genome, whole genome duplications, and a cartoon:
https://doi.org/10.1093/molbev/msaf021
https://tapas.io/episode/3123425
#EvoDevo #MolecularEvolution #Genomics
Like sex chromosomes and supergenes, the non-recombining region accumulates transposable elements, nonsynonymous substitutions, and gene presence/absence polymorphisms—a hallmark of recombination suppression. #MolecularEvolution
5/5
Intriguing: modeling and empirical data support that after whole genome duplication (autotetraploids) genetic variation rises, and mutation load increases because deleterious mutations are masked by additional chromosome copies
https://www.biorxiv.org/content/10.1101/2025.01.12.632621v1
#WholeGenomeDuplication #paralog #MolecularEvolution #PopulationGenetics #Arabidopsis