Table of Contents
Fetching ...

The Hatching-Box: A Novel System for Automated Monitoring and Quantification of Drosophila melanogaster Developmental Behavior

Julian Bigge, Maite Ogueta, Luis Garcia, Benjamin Risse

TL;DR

The paper presents the Hatching-Box, a scalable, open-source system that automates long-term monitoring of Drosophila development directly within standard rearing vials. It combines a purpose-built hardware setup with a YOLOv7-based detection pipeline and an identity-preserving tracker to quantify larvae, pupae, and adults across days, outputting trajectories in HDF5 for downstream analysis. Validation across a curated 470k-object dataset and circadian experiments reproduces known clock phenotypes and demonstrates the system’s ability to reconstruct full life-cycles and group behaviors with minimal manual intervention. The approach offers high-throughput, low-labor automated monitoring suitable for diverse developmental and circadian studies, with potential for integration into broader cultivation workflows.

Abstract

In this paper we propose the Hatching-Box, a novel imaging and analysis system to automatically monitor and quantify the developmental behavior of Drosophila in standard rearing vials and during regular rearing routines, rendering explicit experiments obsolete. This is achieved by combining custom tailored imaging hardware with dedicated detection and tracking algorithms, enabling the quantification of larvae, filled/empty pupae and flies over multiple days. Given the affordable and reproducible design of the Hatching-Box in combination with our generic client/server-based software, the system can easily be scaled to monitor an arbitrary amount of rearing vials simultaneously. We evaluated our system on a curated image dataset comprising nearly 470,000 annotated objects and performed several studies on real world experiments. We successfully reproduced results from well-established circadian experiments by comparing the eclosion periods of wild type flies to the clock mutants $\textit{per}^{short}$, $\textit{per}^{long}$ and $\textit{per}^0$ without involvement of any manual labor. Furthermore we show, that the Hatching-Box is able to extract additional information about group behavior as well as to reconstruct the whole life-cycle of the individual specimens. These results not only demonstrate the applicability of our system for long-term experiments but also indicate its benefits for automated monitoring in the general cultivation process.

The Hatching-Box: A Novel System for Automated Monitoring and Quantification of Drosophila melanogaster Developmental Behavior

TL;DR

The paper presents the Hatching-Box, a scalable, open-source system that automates long-term monitoring of Drosophila development directly within standard rearing vials. It combines a purpose-built hardware setup with a YOLOv7-based detection pipeline and an identity-preserving tracker to quantify larvae, pupae, and adults across days, outputting trajectories in HDF5 for downstream analysis. Validation across a curated 470k-object dataset and circadian experiments reproduces known clock phenotypes and demonstrates the system’s ability to reconstruct full life-cycles and group behaviors with minimal manual intervention. The approach offers high-throughput, low-labor automated monitoring suitable for diverse developmental and circadian studies, with potential for integration into broader cultivation workflows.

Abstract

In this paper we propose the Hatching-Box, a novel imaging and analysis system to automatically monitor and quantify the developmental behavior of Drosophila in standard rearing vials and during regular rearing routines, rendering explicit experiments obsolete. This is achieved by combining custom tailored imaging hardware with dedicated detection and tracking algorithms, enabling the quantification of larvae, filled/empty pupae and flies over multiple days. Given the affordable and reproducible design of the Hatching-Box in combination with our generic client/server-based software, the system can easily be scaled to monitor an arbitrary amount of rearing vials simultaneously. We evaluated our system on a curated image dataset comprising nearly 470,000 annotated objects and performed several studies on real world experiments. We successfully reproduced results from well-established circadian experiments by comparing the eclosion periods of wild type flies to the clock mutants , and without involvement of any manual labor. Furthermore we show, that the Hatching-Box is able to extract additional information about group behavior as well as to reconstruct the whole life-cycle of the individual specimens. These results not only demonstrate the applicability of our system for long-term experiments but also indicate its benefits for automated monitoring in the general cultivation process.

Paper Structure

This paper contains 26 sections, 5 equations, 9 figures.

Figures (9)

  • Figure 1: System overview showing stackable Hatching-Boxes. Standardized rearing vials used to house Drosophila can be placed in the Hatching-Box, which then automatically tracks the population's behavior and provides images and behavior analysis to a central computer.
  • Figure 2: Overview of the proposed hardware architecture. \ref{['sec:results:hardware:fig']} A single Hatching-Box consists of a RaspberryPi 4 with the HQ camera module, an LED controller device (Arduino Uno + custom shield), an Arduino Sense BLE 33 sensor board, as well as a light guide panel, outfitted with IR and white LEDs. \ref{['sec:results:hardware:picture']} Picture of a Hatching-Box with cover removed. \ref{['sec:results:hardware:imaging']} Image as taken by our Hatching-Box with different objects highlighted: third instar larva (cyan), adult fly (blue), empty pupa (red), out-of-focus (yellow) and full pupa (green).
  • Figure 3: \ref{['sec:results:software:fig:map']}, Comparison of average precision (AP), average recall (AR) and mean average precision (mAP) of the YOLOv7 models trained on our Hatching-Box dataset (out-of-focus objects excluded). \ref{['sec:results:dataset:overview']}, Overview of the class distribution of our curated dataset. \ref{['sec:results:software:fig:performance']}, Average inference and tracking time comparison in ms/frame on a CPU (AMD Ryzen 7 3700X 8-Core) and GPU (NVIDIA GeForce RTX 3060 Ti). \ref{['sec:results:software:fig:example_image']},\ref{['sec:results:software:fig:example_image_annotated']}, Crop of an image as taken with our system before and after object detection by YOLOv7. The detected objects are third instar larvae (cyan), adult flies (blue), empty pupae (red), full pupae (green) and out-of-focus (yellow). \ref{['sec:results:software:fig:confusion_matrix']}, Class confusion matrix of the used YOLOv7-tiny model. (For full comparison see Appendix \ref{['appendix:yolov7']})
  • Figure 4: \ref{['sec:results:software:tracking:fig:timemap']}, Positions of eclosion (wildtype Drosophila) over the course of our 14 days circadian experiment. \ref{['sec:results:software:tracking:fig:larvae_tracking']}, Larva locomotion (wildtype Drosophila) over 100 second captured with our system with 1 fps.
  • Figure 5: Comparison of periodicity of selected clock mutants per0, pershort, perlong and wildtype iso31 as recognized by the Hatching-Box. We used the statistical methods of the R package rhetomics. \ref{['sec:results:bio:fig:actogram']}, Double plotted actogram of eclosion events for the different genotypes. \ref{['sec:results:bio:fig:periodogram']}, Lomb-Scargle periodogram of observed mutants scargle1982studies.
  • ...and 4 more figures