Théo Maire
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theomaire.bsky.social
Théo Maire
@theomaire.bsky.social
Post-doc - mosquito behavior @RadboudUMC in Nijmegen with Felix Hol. Previously IVIst with Louis Lambrechts lab @Institut Pasteur. Decoding bugs and/or debugging code.
Very grateful to have been awarded a #MSCA post-doc fellowship! With Felix Hol and Teun Bousema, we will bring BuzzWatch to the field to study mosquito behavior in malaria-endemic regions.

Starting in #RadboudUmc, our first goal is to make BuzzWatch portable enough to be transported by bicycle 🦟🚲🇳🇱.
February 11, 2025 at 6:27 PM
Thanks again to Felix Hol and @lambrechtslab.bsky.social

Also credits to Zhong Wan, Phd student with Felix Hol at RadboudUMC who carried all the experiments and analysis with Anopheles and was played a key role in developing the method, especially the Dutch version!

More news on that soon!
January 27, 2025 at 5:35 PM
🥵 This was a lot of examples, yet only scratched the surface of what BuzzWatch can teach us about mosquito behavior. Have a burning question that BuzzWatch could help answer? Start here:

theomaire.github.io/buzzwatch/

and don't hesitate to contact me or Felix!
January 27, 2025 at 5:35 PM
We tested mosquito responses to multiple daily stimulations over 9 days

Ae. aegypti showed a 2-fold higher response during the day than at night (expected from a day biting mosquito:) ), although spontaneous flight activity without host cues was nearly the same and close to zero at those times !
January 27, 2025 at 5:35 PM
The movie shows mosquitoes quickly flying to the heated bottom window and attempting to insert their proboscis, demonstrating their heat-seeking response (and that they are not that smart because a heating peltier elt. will provide a good blood-meal..)
January 27, 2025 at 5:35 PM
As a final application example, we added a simple "host-seeking" module to measure mosquito responses to short pulses of CO₂ and heat at specific times of the day.
January 27, 2025 at 5:35 PM
As environmental perturbation, we tested the impact of increasing the photoperiod from 12 to 20 hours of light per day.

Mosquitoes quickly adapted with a new complex rhythm but also showed subtle shifts over time.

This is most striking in the PCA graph, where each dot represents a single day!
January 27, 2025 at 5:35 PM
In these experiments, mosquitoes had no egg-laying site. We thus tested if egg-laying could reverse blood-feeding induced changes.

➡️ Answer: Yes, but only partially.

Overall, the effects of blood-feeding and egg-laying are small, yet consistent and measurable.
January 27, 2025 at 5:35 PM
We examined the effect of blood feeding 🩸 by monitoring mosquitoes before and after a blood meal.

➡️Following a 2-day period of full rest, we observed subtle changes in their daily rhythm.

➡️Interestingly, these changes were long-lasting and showed no sign of gradual decline.
January 27, 2025 at 5:35 PM
Fun side quest : in the global pattern method, datasets from various species can be easily compared, here we show for :

➡️Ae. aegypti (Aaa and Aaf)
➡️Ae. albopictus
➡️An. stephensi, gambiae, and coluzzi

PC1 represents day vs. night activity, while PC2 indicates total activity.
January 27, 2025 at 5:35 PM
To assess this observation, we developed 2 statistical tools

➡️A "local" tool resembling a "barcode" for easy comparison of different features (e.g. sugar feeding)

➡️A "global" tool using dimensional reduction on daily profiles

Both confirmed that "Aaa" is distinct due to increased midday activity!
January 27, 2025 at 5:35 PM
First, we used the great panel of Ae. aegypti colonies (tested 10!) from @lambrechtslab.bsky.social and found a clear pattern :

➡️the globally invasive subspecies "Aaa" is more active (fly more) during midday compared to the African "Aaf," but not during the morning or evening peaks.
January 27, 2025 at 5:35 PM
January 27, 2025 at 5:35 PM
Once all videos are analyzed, we can combine the data to perform multi-scale analysis. This includes examining flight trajectories in seconds, daily rhythms over hours, and long-term trends over days and weeks.
January 27, 2025 at 5:35 PM
We created a Python GUI app for mosquito video analysis, tracking flying and resting behaviors. By using abundant footage, we easily generate a clear background devoid of mosquitoes and utilize basic blob detection and tracking—no deep learning and manual labelling needed.
January 27, 2025 at 5:35 PM
To control the environment, you can use options like building a custom box with LED strips or placing everything inside a climatic chamber. Just unleash your inner mosquito house architect! 🦟🏠 (and use constant infrared illumination!)
January 27, 2025 at 5:35 PM
How to make it happen?

➡️Use laser cut acrylic, Raspberry Pi computer, cheap cameras, glue and white paper!

Instructions and templates are gathered here :
theomaire.github.io/buzzwatch/co...

otherwise feel free to contact me or Felix directly!
January 27, 2025 at 5:35 PM
What BuzzWatch does:

1. Automatically film mosquitoes in a transparent cage continuously, at 25 FPS, for several weeks (low resolution, about 10GB/day)

2.Analyze each 20-minute segment independently to track flying and resting mosquitoes

3.Extract flight and sugar feeding activity over weeks
January 27, 2025 at 5:35 PM