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The ‘dance’ of life: visualizing metamorphosis during pupation in the blow fly Calliphora vicina by X-ray video imaging and micro-computed tomography

Martin J. R. Hall, Thomas J. Simonsen, Daniel Martín-Vega

Published 25 January 2017.DOI: 10.1098/rsos.160699


Abstract

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.

Data accessibility

The videos reported in this paper can be accessed at the Dryad Digital Repository: http://dx.doi.org/10.5061/dryad.5p5cm [47].

Authors' contributions

M.J.R.H., T.J.S. and D.M.-V. conceived the study and all contributed to the interpretation of the analysis and to writing the manuscript. M.J.R.H. and D.M.-V. conducted the experiments which were analysed by D.M.-V. All authors gave final approval for publication.

Competing interests

The authors declare no competing interests.

Funding

D.M.-V. was supported by an EC-funded Marie Curie Intra-European Fellowship (FP7-PEOPLE-2013-IEF n: 624575) and a grant from the Mactaggart Third Fund.

Acknowledgements

We are grateful to Farah Ahmed and Dan Sykes of the micro-CT unit of the NHM's Imaging and Analysis Centre for their technical assistance and advice. We are also grateful to Paola Magni for directing us to the work of Thévenard.

Footnotes

Electronic supplementary material is available online at https://dx.doi.org/10.6084/m9.figshare.c.3659360.

Received September 13, 2016 Accepted December 8, 2016.

© 2017 The Authors.

Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original author and source are credited.

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