I’m obsessed with brittle stars: fish often nip off bits of their arms but they regenerate

Prof Martin Solan in his brittle stars research laboratory at the National Oceanography Centre in Southampton. The creatures can regenerate even when they have lost all of their arms and half of the body. Photograph: Gareth Iwan Jones/The Guardian

Brittle stars have a lot of remarkable features as a species. Many of them are bioluminescent and can flash blue light; some will have patterns and do displays. These slender relatives of starfish can be very beautiful to look at and come in a range of colours – in the tropics, for example, they can be red, black or orange. And they’ve got spines all over them, so they can look quite ornate.

They can also regenerate. Fish and other creatures will often nip off bits of their arms – known as sublethal predation – so they are constantly regenerating themselves. You can even break off all their arms, and sometimes even half the disc, and the brittle star will still regenerate.