Venus flower basket

Venus' Flower Basket
Scientific classification
Kingdom:	Animalia
Phylum:	Porifera
Class:	Hexactenellida
Family:	Euplectellidae
Genus:	Euplectella
Species:	E. aspergillum
Binomial name
Euplectella aspergillum Owen, 1841

The Venus' Flower Basket, or Euplectella aspergillum, is the only Hexactenellida in the phylum Porifera to be used in hobbyists' aquariums. This is because Hexactinellid sponges are mainly deep ocean sponges that are not suitable for domestic aquarium environments. In traditional Asian cultures, this particular sponge was given as a wedding gift because certain bioluminescent shrimp tend to form a symbiosis with them. The sponge houses two small shrimp, a male and a female, who live out their lives inside the sponge. They breed, and when their offspring are tiny, the offspring escape to find a Venus Flower Basket of their own. The shrimp inside of the basket clean it, and in return, the basket provides food for the shrimp by trapping it in its fiberglass-like strands, and then releasing it into the body of the sponge for the shrimp. It is also speculated that the light given off by the sponge may attract other small organisms which the shrimp eat.

They were also extremely popular in Victorian England, and one could easily fetch five guineas, equivalent to over £500 today.

Bio-inspiration

Optical fibers and solar cells

The glassy fibers that attach the sponge to the ocean floor, 5-20 cm long and thin as human hair, are of interest to fiber optics researchers. The sponge extracts silicic acid from seawater and converts it into silica, then forms it into an elaborate skeleton of glass fibers. Other sponges such as the orange puffball sponge can also produce glass biologically. The current manufacturing process for optical fibers requires high temperatures and produces a brittle fiber. A low-temperature process for creating and arranging such fibers, inspired by sponges, could offer more control over the optical properties of the fibers. These nano-structures are also potentially useful for the creation of more efficient, low-cost solar cells.

Material strength

These sponges skeletons have amazing geometric configurations, which have been extensively studied for their stiffness, yield strength, and minimal crack propagation. An aluminum tube (aluminum and glass have similar elastic modulus) of equal length, effective thickness, and radius, but homogeneously distributed, has 1/100^th the stiffness.

References

• [1] "Glassy sponge has better fiber optics than man-made", William McCall, AP, August 20, 2003

• [2] "Biological glass fibers: Correlation between optical and structural properties" Joanna Aizenberg et al. PNAS 2004

• [3] "Silicon and Sun," Kevin Bullis, Technology Review Nov./Dec. 2006