The Bluebottle or Portuguese Man of War is not a single animal but a colony of four kinds of highly modified individuals (zooids). The zooids are dependent on one another for survival. The float (pneumatophore) is a single individual and supports the rest of the colony. The tentacles (dactylozooids) are polyps concerned with the detection and capture of food and convey their prey to the digestive polyps (gastrozooids). Reproduction is carried out by the gonozooids, another type of polyp.
The float is a bottle or pear-shaped sac that can exceed 15 cm. It is mainly blue, though its upper margin may show delicate shades of green or pink. It is a living, muscular bag that secretes its own gas, which is similar to air. The float has aerodynamic properties and it seems likely that sailing characteristics may be modified by muscular contraction of the crest.
Know more:
http://australianmuseum.net.au/bluebottle#sthash.0q5PADZl.dpuf
Photo credit: Matty Smith
Photo via HousingCamera
http://www.housingcamera.com/blog/featured-photographers/weekly-featured-underwater-photographer-matthew-smith#.Vqm3Qbnn671
More of his work:
http://www.mattysmithphoto.com/
#biodiversity #marinecritters #bluebottle
wow, I just am beginning to understand how complicated the business of little animals making up big animals really is. We're realizing, for instance, that our own body could be described as being made up from a large ecosystem of different species of animals all working together.
ReplyDeletePhysalia Utriculus .. Marine hydrozoan of the order Siphonophora found in the Indian and Pacific oceans .. their toxic nematocysts can remain potent for weeks or months in moist conditions .. P. Utriculus is responsible for most of the reported injuries on Australian beaches .. On the east coast of Australia 10,000 to 30,000 stings from animals of the genus Physalia per year are reported ..
ReplyDeleteI've seen these guys all over the beaches of the PNW after a big storm.
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