January 2017 cover
This end up. Larva of the brachiopod Terebratalia transversa. Image by Jürgen Berger and Gáspár Jékely. Cover design by Allen Beattie.
Scanning electron microscopic image of the larva of the brachiopod Terebratalia transversa. Brachiopods are marine, sessile animals. The protostomic development leads to this 300-µm-long larva that is equipped with long chaetae that facilitate floating and defence. Anterior up.
From 'The developmental basis for the recurrent evolution of deuterostomy and protostomy.' Martin-Duran et al. Nature Ecology & Evolution 1; 0005 (2016)