OH, MEDUSA: JELLYFISH. A HALF BILLION YEARS IN THE MAKING

Mesmerizing, delicate and seemingly impossible — this lovely luminescent denizen of the sea has been living in our oceans for more than half a billion years.

Jellyfish are found all over the world, from surface waters to our deepest seas — and they are old. They are some of the oldest animals in the fossil record.

Jellyfish are not fish at all. These gossamer wonders evolved millions of years before true fish.

Jellyfish and sea jellies are the informal common names given to the medusa-phase or adult phase of certain gelatinous members of the subphylum Medusozoa, a major part of the phylum Cnidaria — more closely related to anemones and corals.

The oldest conulariid scyphozoans appeared between 635 and 577 mya in the Neoproterozoic of the Lantian Formation in China. Others are found in the youngest Ediacaran rocks of the Tamengo Formation of Brazil, c. 505 mya, through to the Triassic. Cubozoans and hydrozoans appeared in the Cambrian of the Marjum Formation in Utah, USA, c. 540 mya.

I have seen all sorts of their brethren growing up on the west coast of Canada in tide pools, washed up on the beach and swam amongst thousands of Moon Jellyfish while scuba diving in the Salish Sea. Their pulsating movements are marvellous.  

In the Kwak̓wala language of the Kwakiutl or Kwakwaka'wakw, speakers of Kwak'wala, of the Pacific Northwest, jellyfish are known as ǥaǥisama.

The dreamy blue and purple ǥaǥisama you see here is but one of a large variety of colours and designs. Jellyfish come in bright yellow, orange, clear with pink spots and are often luminescent.