Dr Andrew Gillis shows us an embryonic skate head and explains how the red denticles dotted all over it have very similar properties to human teeth.
Dr Gillis: This is a picture of an elephant fish embryo. The elephant fish lives in deep water off the coasts of Australia and New Zealand, but migrates annually into shallow coastal bays to lay their eggs. I study the embryonic development of elephant fish, by collecting their eggs by SCUBA diving at their egg-laying grounds. Normally, an elephant fish embryo will live in their egg and feed off of their yolk supply for 7 to 10 months before hatching out as a completely self-sufficient juvenile. However, these embryos may also be cultured outside of their egg cases, as seen here. This allows us to observe and photograph the development and growth of this unusual fish.
The diameter of the petri dish in the elephant fish picture is 10cm.
Under the Microscope is a collection of videos that show glimpses of the natural and man-made world in stunning close-up. They are released every Monday and Thursday and you can see them here: bit.ly/A6bwCE
Explore further: How to Grow a Bigger Brain
More info: pdn.cam.ac.uk/~jag93