Embryo movement is more frequent in avian brood parasites than birds with parental reproductive strategies.

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McClelland, Stephanie C  ORCID logo  https://orcid.org/0000-0002-8763-2291
Reynolds, Miranda 
Cordall, Molly 

Movement of the embryo is essential for musculoskeletal development in vertebrates, yet little is known about whether, and why, species vary. Avian brood parasites exhibit feats of strength in early life as adaptations to exploit the hosts that rear them. We hypothesized that an increase in embryonic movement could allow brood parasites to develop the required musculature for these demands. We measured embryo movement across incubation for multiple brood-parasitic and non-parasitic bird species. Using a phylogenetically controlled analysis, we found that brood parasites exhibited significantly increased muscular movement during incubation compared to non-parasites. This suggests that increased embryo movement may facilitate the development of the stronger musculoskeletal system required for the demanding tasks undertaken by young brood parasites.


Funder: National Science Foundation; Id: http://dx.doi.org/10.13039/100000001

Funder: Tanzanian Commission for Science and Technology (COSTECH)

Funder: NERC

Funder: Max-Planck-Gesellschaft; Id: http://dx.doi.org/10.13039/501100004189

Funder: Ministry of Education; Id: http://dx.doi.org/10.13039/501100002701

Funder: Tanzania Wildlife Research Institute (TAWIRI)

Funder: University of Cape Town; Id: http://dx.doi.org/10.13039/501100007112

Funder: German Academic Exchange Service (DAAD)

Evolution, Research articles, avian brood parasites, co-evolutionary arms race, embryonic development, muscle development
Journal Title
Proc Biol Sci
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The Royal Society
Biotechnology and Biological Sciences Research Council (BB/J014109/1)