Cayman Sponge Belt

[ianr33]

Anybody know anything about the Sponge Belt in Cayman (Or anywhere else for that matter!) This is the zone between about 200 feet and 400 feet where there is not enough light for corals but instead large sponges predominate.

In particular I would be interested in how old these sponges are. The environmental conditions (light,temperature) must be pretty much constant and even the worst Hurricanes will not reach that deep.

My guess is that some of these sponges could be very,very,old ??

 

[ianr33]

Thought I would take the liberty of bumping my own thread as its been a while

Heading to Cayman tomorrow, doing some research came across this fascinating fact:

<<In March 2009, scientists released the results of their research on deep-sea (depths of ~300 to 3,000 m) corals throughout the world. They discovered a subdivision of Black Coral, A. Leiopathes sp. specimens, to be among the oldest continuously living organisms on the planet; around 4,265 years old. They show that the "radial growth rates are as low as 4 to 35 micrometers per year and that individual colony longevities are on the order of thousands of years". >>

Black coral - Wikipedia, the free encyclopedia

Seems possible that some Black Corals could be older than Bristlecone Pines, and thus the oldest living thing on the planet ??

 

[jva]

From the original article:

Leiopathes is the oldest skeletal-accreting marine organism known and, to the best of our knowledge, the oldest colonial organism yet found. Based on 14C, the living polyps are only a few years old, or at least their carbon is, but they have been continuously replaced for centuries to millennia while accreting their underlying proteinaceous skeleton.

Roark EB, Guilderson TP, Dunbar RB, Fallon SJ, Mucciarone DA. 2009. Extreme longevity in proteinaceous deep-sea corals. Proc Natl Acad Sci USA 106(13):5204-8. doi: 10.1073/pnas.0810875106.

If I recall correctly, the Bristlecone Pine is 'only' the oldest known living individual plant, whereas some colonial plants are estimated to be older.

Having said that, I guess the age of deep sea colonial organisms has been studied far less extensively than that of colonial plants, so may be you're right. Who knows?

I don't know much about this subject, anyway.