We have a lot in common with this tadpole. Young African claw-toed frogs, Xenopus laevis, are studied all over the world because their development is similar to our own, allowing logical leaps to be made across species. Pictured from above through a microscope, this tadpole’s head (which is conveniently transparent) has been coloured artificially to highlight developing organs and tissues. Nerves, shown in blue, run from the early brain (in the centre) to the ball-like olfactory placodes of the developing nose (on the right). The tiny snowflake-shaped cells are melanocytes, destined to migrate all over the body defining skin colour. But it’s not just the tadpole’s head that's useful to us – studies of Xenopus tails, which regenerate after injury, have revealed ‘repair’ genes similar to those found inside us. With another jump between species, these tadpoles are providing vital clues about how human wounds heal.
Written by John Ankers
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.