Each individual in this colony lives for about seven days and then dies by 'programmed cell death.' Here new individuals are being budded off lateral to the smaller senescent ones.
Adjacent Botryllus colonies will fuse if they share one allele of a common 'fusibility gene.' Here, lacking such an allele, the colonies recognize each other as non-self and rejection occurs in a reaction analogous to human organ rejection following transplantation. Field of view 15 mm.
This beautiful tunicate sheds its gametes to the sea, and fertilization is external. Two solitary corals, Balanophyllia elegans sit adjacent to it. Depth 14 m.
Cosmopolitan organism found worldwide. Individual zooids are hermaphroditic; they do not self fertilize. Non-feeding 'tadpole' larvae settle to found new colonies. The larvae have the characteristics of a vertebrate embryo making them relatives of ours. Field of view 15 mm.
