Hiroshi Arai

Happy New Year!! 🎉

TiG welcomes 2026 with a new issue! Topics include the ethics of de-extinction, AlphaGenome, DNA-based taxonomies, TEs in cancer, and more: shorturl.at/Zp7zw

Thanks to @haraipapilio.bsky.social for the cover image - a female butterfly that may harbor male-killing symbionts!

Insects are often coinfected with closely related bacterial endosymbionts (such as Wolbachia), which makes isolating and assembling individual genomes challenging.
This work was a collaboration with Waseda University and AIST — please also check out their system here:
unit.aist.go.jp/cbbd-oil/en/...

Single-cell genome analysis of a feminizing Wolbachia in Eurema butterflies reveals a shared origin with male-killing Wolbachia Wolbachia is a ubiquitous endosymbiont in arthropods that is maternally transmitted and affects host reproduction in various ways. Among these, skewing the host sex ratio towards females, either by ki...

Our new paper is now out in Microbial Genomics!
Available here: doi.org/10.1099/mgen...
(Microbiology Society, @microbiologysociety.org)

We established a genome of an unculturable bacterial endosymbiont (Wolbachia, wFem) that feminises Eurema butterflies using a single-cell–based technique.

📣CALL FOR APPLICATIONS!!

The next deadline for the #GodfreyHewitt mobility award is 31st January 2026. Open to ECRS in support of research trips or lab visits.

For more information, eligibility and how to apply: eseb.org/prizes-fundi...

Cr. to Shen Tian

My main PhD work @monteirolab.bsky.social is now in @natecoevo.nature.com! We found a Hox gene promoter that helps butterflies🦋adjust their wing eyespots in response to seasonal temperatures🍃🍂, shedding light on the evolutionary origin of phenotypic plasticity. 1/9 www.nature.com/articles/s41...

We created an ‘unsexy’ moth that could be the key to greener pest control Scientists have learned how to turn off moths’ sex signals – this could help farmers fight pests without pesticides.

A single “sexy” gene can help combat one of the most destructive fruit pests. By deleting the gene that lets female moths produce their mating scent, researchers created an “unsexy” moth and showed a way to turn insect attraction into a powerful pest control tool.
theconversation.com/we-created-a...

Colonization, diversification and speciation of the genus Hipparchia (Lepidoptera: Nymphalidae) in the Canary Islands Abstract. The Canary Islands harbor numerous endemic species, showcasing a wide array of colonization and diversification patterns. Butterflies belonging t

Very cool paper from @rogervilalab.bsky.social on the Canary islands Hipparchia butterflies just came out! Each island has its own species, seems like no gene flow between the islands!
academic.oup.com/isd/article/...

🚨 New pub alert! Check out our latest one that showcases how chemical and genetic innovations can recreate complex host–symbiotic interactions in the absence of the symbiont.

www.cell.com/cell-reports...

Beyond Wolbachia—Can a small molecule control insect reproduction? Kaur et al. demonstrate reduced histone acetylation as a key mechanism underpinning Wolbachia’s paternal-effect embryonic lethality trait in Drosophila melanogaster. Recapitulation of this trait by in...

#Wolbachia has puzzled scientists with its power to rewire insect reproduction. What if I tell you that we found one of the keys Wolbachia use to rewire its host AND a small molecule inhibitor uses this key to mimic what this microbe has mastered for millions of years.

www.cell.com/cell-reports...

🌍🦋 Across 6 continents, 21 sites & 15,000 paper moths, we joined a worldwide experiment led by @wlallen.bsky.social & Iliana Medina, showing how ecological context shapes the evolution of animal colouration.

Proud to be part of this global team effort: doi.org/10.1126/scie...

A white-fronted bee-eater (Merops bullockoides) decides whether to consume a warningly colored white-barred acraea butterfly (Telchinia encedon). Photo (c) Mike Rowe

📢🦋 Our paper ‘Global selection on insect antipredator coloration’ is out and featured on the cover of @science.org

We ran a huge experiment to find out how ecological context favours camouflage and warning colouration as antipredator strategies. 1/6

www.science.org/doi/10.1126/...

Ecology and evolution of virulence Silva and King discuss the concept of virulence and the ecological and evolutionary factors that shape it.

Interested in #virulence? Not sure what it is - or how to explain it? Just curious? 🧐🦠🧬🦋

@kayla-king.bsky.social and I just wrote a Primer for @currentbiology.bsky.social on the ecology and evolution of virulence!

Check it below and share :)

#MicroSky #EvoSky #pathogens

Evolutionary Diversification and Functions of the Candidate Male Killing Gene wmk Abstract. Symbiont-mediated male killing (MK) is a mechanism that selectively eliminates male offspring, often by disrupting sex-specific developmental pro

New accepted manuscript (preprint) on the evolution, phylogenetic types, expression, and fxns of a male-killing gene from a phage in a common endosymbiont of animals. Credit to many lab coauthors and led by Dr. Emilie Lefoulon. Lots of fun and insights in this one. academic.oup.com/gbe/advance-...

Striking diversity of male-killing symbionts and their mechanisms Symbiosis is a fundamental characteristic of eukaryotic biology. Arthropods, including insects, often harbor maternally inherited endosymbiotic microb…

Our new review paper with @daisukekageyama.bsky.social is out in Trends in Genetics (@cp-trendsgenetics.bsky.social)!
We summarise the current knowledge on the diversity of male-killing microbes and their mechanisms.

Available here:
🔗 www.sciencedirect.com/science/arti...

Check our latest paper in @currentbiology.bsky.social about the unique sex determination system in Nautilus ➡️ XX/XY chromosomes unlike other cephalopods (ZZ/Z0).
with @reef-combo.bsky.social and @anariesgo.bsky.social et al., and led by Hector Torrado.
Get it: authors.elsevier.com/c/1lbs~_LsQS...

I had the pleasure of presenting on MK microbes at #ESEB2025 (JMS lecture) — many thanks to everyone who attended! I also learnt a lot from inspiring studies — thanks to all the speakers. On the way, I was fortunate to come across a beautiful book: 흰 (The White Book, Han Kang)

Recent achievements:
Our review paper on the striking diversity of male-killing (MK) symbionts and mechanisms has just been accepted in Trends in Genetics! I’m grateful to the reviewers for their thoughtful and valuable suggestions, and I look forward to sharing the article once it’s published

Our New Paper is out! Great work by Mashaneh Ahrar and the team - thank you all, especially @makaefer.bsky.social and Greg Hurst (is he on Bsky???)! TBC :)

A license to kill Bacteria belonging to the Wolbachia family employ distinct genes to kill the male offspring of different insect species.

Wolbachia bacteria hijack insect reproduction by killing off males, but it turns out they don’t use the same weapon in every species. New research uncovers species-specific genes with a license to kill.

Thank you very much, Seth! (from Okinawa)

Prophage-encoded Hm-oscar gene recapitulates Wolbachia-induced male-killing in the tea tortrix moth Homona magnanima Oscar homologs play a conserved role in Wolbachia-induced male-killing in Lepidoptera but not in other insects, highlighting the evolution of diverse male-killing mechanisms induced by Wolbachia.

Our final version of eLife paper (VOR) is now out! (doi.org/10.7554/eLif...). I investigated functions of wmk and Oscar homologs in a native host (moth) with @daisukekageyama.bsky.social and others:))

Very happy to receive two great news after the long flight : current biology (doi.org/10.1016/j.cu...) and JMS prize (eseb.org/prizes-fundi...)

This year's Runner-Up for the JMS Prize is Kaleda Denton!

Her research was highly commended by the Prize Committee and you can read more about her work here:

eseb.org/prizes-fundi...

⭐2025's John Maynard Smith Prize Winner is Hiroshi Arai⭐

Hiroshi will give the JMS Prize Lecture in Barcelona this August at #ESEB2025 @eseb2025.bsky.social

Read more about his prize-winning research here: eseb.org/prizes-fundi...

Evolution of Wolbachia male-killing mechanism within a host species Male-killing bacterial symbionts, prevalent in arthropods, skew population sex ratios by selectively killing male progeny, profoundly impacting ecolog…

@haraipapilio.bsky.social paper on evolution of Wolbachia MK mechanism through prophage acquisition in molina butterflies - avoiding suppression by the host. Now out! #symbiosky www.sciencedirect.com/science/arti.... With @daisukekageyama.bsky.social @bolinabug.bsky.social and others

Evolution of Wolbachia male-killing mechanism within a host species Male-killing bacterial symbionts, prevalent in arthropods, skew population sex ratios by selectively killing male progeny, profoundly impacting ecology and evolution of their hosts. Male-killing is a ...

New preprint from @haraipapilio.bsky.social with @bolinabug.bsky.social @daisukekageyama.bsky.social and others not on bluesky #symbiosky www.biorxiv.org/content/10.1...