Search bioRxiv⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.1101/2023.03.03.531017

Ultra-fast micro-CT of an unrestrained live insect

Davranoglou, L.-R.·Mortimer, B.·Schelpuetz, C. M.·Taylor, G. K.
View original source ↗Export metadata ↓

Abstract

Micro-CT has revolutionized functional morphology by enabling volumetric reconstruction of biological specimens at micrometre scales, but its accuracy is compromised by fixation artefacts. State-of-the-art in vivo imaging avoids this, but still requires subjects to be tethered, anaesthetized, or stained. Here we use ultra-fast synchrotron-based micro-CT to produce the first 3D scan of an unrestrained living organism at micrometre resolution, demonstrating the potential of this method in physiology, behaviour, and biomechanics.

Explore related subjects

zoologyPreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Davranoglou, L.-R., Mortimer, B., Schelpuetz, C. M., Taylor, G. K.. 2023-03-06. Ultra-fast micro-CT of an unrestrained live insect. https://doi.org/10.1101/2023.03.03.531017

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

Sex-linked genomic variation reveals reproductive skew and male-biased dispersal in polygynous sea lions

Sex-biased dispersal and the resulting asymmetry in gene flow are important factors in evolution. However, their quantification in natural populations remains challenging, not least because sex-specific reproductive skew, as reflected in the mating system, further influences the relative contributions of males and females to the genetic pool of subsequent generations. Incorporating information from mitochondria (MT) and sex chromosomes (X, Y) alongside the more commonly used autosomal markers (AUT) provides a promising framework to partly disentangle confounding processes. Here, we exemplify this approach in two closely related, polygynous species with observational evidence for male-biased dispersal, the Galapagos sea lion (GSL) and the Steller sea lion (SSL). Using whole-genome resequencing data, we leveraged genetic variation among all four genomic compartments, representing genetic variation with female-only (MT), mixed (X, AUT) and male-only (Y) inheritance, to obtain information on the mating system and test for sex-specific migration across geographic and environmental boundaries. For GSL, genomic signatures were consistent with mild polygyny and a moderately elevated rate of male migration, particularly across habitat boundaries. In SSL, male reproductive skew was substantially greater, and male-biased migration was more pronounced and less habitat-dependent. Our results align with the species' life history and support a link between mating system and dispersal, but were also impacted by confounding biological processes and bioinformatic choices. This study highlights the value and challenges of population genomic approaches integrating multiple genomic compartments to infer variation in individual behaviours.

zoology↗
bioRxiv2026

Impact of iron-enriched diets on the nutritional composition and microbiome diversity of house crickets (Acheta domesticus)

Iron deficiency (ID) and iron-deficiency anaemia (IDA) pose significant global health challenges. ID and IDA are particularly widespread in Sub-Saharan Africa and South Asian countries, where reliance on plant-based foods is high. Edible insects provide an alternative nutritious food source, rich in both protein and essential minerals and trace elements. Little is known about how dietary iron manipulation affects the trace element bioaccumulation and microbiome community composition of edible insects. This study examined the impact of dietary iron supplementation on the growth, survival, nutrient profile, and microbiome of Acheta domesticus. Experimental diets were formulated using iron (II) sulphate heptahydrate, resulting in final iron concentrations ranging from 333.45 mg Fe/kg (control diet) to 6923.39 mg Fe/kg (100 mM Fe diet). Iron supplementation significantly altered the cricket trace element profile, with iron levels increasing fivefold from basal 21.38 mg/kg to 118.34 mg/kg in the highest iron treatment group. Concurrently, manganese levels showed a strong negative correlation with dietary iron, while zinc and cadmium displayed non-significant downward trends. High-iron diets statistically altered dry matter, chitin, and TBARS, whereas carbohydrates, protein, glycogen, and lipids remained stable. Amino acid profiles shifted progressively, with branched-chain, sulphur-containing, and aromatic amino acids peaking in the 25 mM Fe group. In contrast, the diversity and overall structure of the microbial community remained unaffected across all treatments. In conclusion, tailoring dietary iron can significantly boost the iron content of Acheta domesticus without compromising host survival or altering core microbial structures. To optimize insect rearing strategies aimed at alleviating human micronutrient deficiencies, a feeding dose of 10-25 mmol Fe/kg is recommended.

zoology↗
bioRxiv2026

Tardigrades survive reversible dormancy during spaceflight: In-orbit revival, post-flight recovery, and transcriptomic responses

Long-duration space missions face substantial challenges, including limited resources and prolonged exposure to microgravity and radiation. Transporting organisms in a dormant state and reviving them at their destination could help overcome some of these limitations. However, the feasibility of this strategy has not been experimentally demonstrated in multicellular animals beyond Earth. Here, we investigated this possibility using tardigrades, microscopic invertebrates capable of entering a reversible state of dormancy. We demonstrate that dormant tardigrades can withstand near-absolute-zero temperatures (~12 mK), near-vacuum conditions (10-9 mbar), high doses of ionizing radiation (3000 Gy), and complete desiccation. We transported dormant tardigrades to the International Space Station (ISS). They were revived aboard the ISS, subsequently returned to a dormant state, and successfully revived again following their return to Earth. Approximately 45% of the space-flown tardigrades survived the 64-day experimental period. This included two dormancy-revival cycles, 18 days aboard the ISS, and prolonged periods without food or water. Importantly, surviving tardigrades retained their reproductive capacity. Transcriptomic analysis of ISS-exposed tardigrades revealed upregulation of genes associated with protein folding and stress responses, accompanied by downregulation of genes involved in energy metabolism and protein synthesis, providing insights into their molecular responses to the spaceflight environment. Together, these findings demonstrate the successful revival and re-induction of dormancy in a multicellular animal beyond Earth and establish an experimental foundation for exploring dormancy-based strategies for future long-duration space missions.

zoology↗