The dramatic metamorphosis from larva to adult of insect orders such as Diptera cannot usually be witnessed because it occurs within an opaque structure. For the cyclorrhaphous dipterans, such as blow flies, this structure is the puparium, formed from the larval cuticle. Here, we reveal metamorphosis within the puparium of a blow fly at higher temporal resolution than previously possible with two-dimensional time-lapse videos created using the X-ray within a micro-computed tomography scanner, imaging development at 1 min and 2 min intervals. Our studies confirm that the most profound morphological changes occur during just 0.5% of the intrapuparial period (approx. equivalent to 1.25 h at 24°C) and demonstrate the significant potential of this technique to complement other methods for the study of developmental changes, such as hormone control and gene expression. We hope this will stimulate a renewed interest among students and researchers in the study of morphology and its astonishing transformation engendered by metamorphosis.
Open Science - Metamorphosis Movies S1
Time-lapse X-ray video of pupation in Calliphora vicina, beginning at 28 hours after pupariation (00:00, h:min). Images are displayed at one frame per second, each image captured at intervals of one-minute (i.e. 60 x natural speed). The pupa was imaged with the dorsal surface uppermost and its head at the top of the video. See text and Figure 1 for further explanation.
Open Science - Metamorphosis Movies S2
Time-lapse X-ray video of pupation in six specimens of Calliphora vicina, beginning at 28 hours after pupariation (00:00, h:min). Images are displayed at one frame per second, each image captured at intervals of two-minutes (i.e. 120 x natural speed). The puparia on the top row (A-C) were imaged with the dorsal surface uppermost (specimen B inclined slightly to the left) while the puparia on the bottom row (D-F) were imaged with their left side uppermost. All puparia have their head at the top of the video. See text and Figure 1 for further explanation. Note that the gas bubble in specimen D has already started to move from the pupa at the start of the video and that the process starts next in specimen E then sequentially in specimens B, C, A and finally in F.
Open Science - Metamorphosis Movies S3 - 6hAPsagittal_24fps
Stack of micro-CT based virtual sagittal sections of Calliphora vicina puparium at six hours after pupariation, scanned from left surface to right surface, dorsal surface on right-hand side of video, head at top. See text and Figure 2B for further explanation. Note the indentation in the cuticle of the puparium on the dorsal surface of the anterior end.
Open Science - Metamorphosis Movies S4 - 6hAPhorizontal_24fps
Stack of micro-CT based virtual horizontal sections of Calliphora vicina puparium at six hours after pupariation, scanned from dorsal surface to ventral surface, head at top. See text and Figure 2D for further explanation. Note the indentation in the cuticle of the puparium on the dorsal surface of the anterior end.
Open Science - Metamorphosis Movies S5 - 24hAPsagittal_24fps
Stack of micro-CT based virtual sagittal sections of Calliphora vicina puparium at 24 hours after pupariation, scanned from left surface to right surface, dorsal surface on right-hand side of video, head at top. See text and Figure 2F for further explanation.
Open Science - Metamorphosis Movies S6 - 24hAPhorizontal_24fps
Stack of micro-CT based virtual horizontal sections of Calliphora vicina puparium at 24 hours after pupariation, scanned from dorsal surface to ventral surface, head at top. See text and Figure 2H for further explanation.
Open Science - Metamorphosis Movies S7 - 30hAPsagittal_24fps
Stack of micro-CT based virtual sagittal sections of Calliphora vicina puparium at 30 hours after pupariation, scanned from left surface to right surface, dorsal surface on right-hand side of video, head at top. See text and Figure 2J for further explanation.
Open Science - Metamorphosis Movies S8 - 30hAPhorizontal_24fps
Stack of micro-CT based virtual horizontal sections of Calliphora vicina puparium at 30 hours after pupariation, scanned from dorsal surface to ventral surface, head at top. See text and Figure 2L for further explanation.