Among the many bizarre and little known species on the planet are many masters of engineering that create unusual materials which they use to build complex living quarters. Paper was being manufactured by paper wasps and other species long before humans discovered how to make it; another 'human invention' predated by its animal kingdom equivalent is glass.
Glass has been produced for about 400 million years by a simple subclass of the sponge phylum (hexactinellida), much more recently named the Glass Sponge. The glass sponge builds its own exquisite lattice or lace-like skeleton from a geometric network of silica spicules (needle-like fibres).
The sponges take tiny bits of silica (billionths of metres long) from their surroundings and apply a sort of cement, or 'glue', to bind the bits together. It becomes layered, much like fibreglass or plywood, which accounts for the additional durability and flexibility. The shape of the hexaradiate1 spicules (fibres) can be either 'triaxone' (the three axes intersect at right angles), triangular, or polygonal depending on the species. Most lack calcareous (spongin) components in the skeleton proper.
The silica fibres they construct underwater at low temperatures (compared to temperatures in human glass making), are in ways superior to fibre-optic cables produced topside. They have a flexibility and strength that surpasses the man-made version, and are capable of filtering nutrients from the seawater.
The basket-weave construction gives the glass sponge some advantages in the harsh, deep-sea environment (100 metres to three kilometres) and some of the species have formed symbiotic relationships with shrimp who use the sponge as their home and breeding place. The structures rival the engineering complexities of modern high-rise buildings.
Glass Sponge Species
There are about five hundred species of Glass Sponge. The species vary in shape and size, some can grow to a length of more than 30cm. The skeletal shape of the basket often has a crown of fibres at its base - that may help the sponge anchor itself. They have a rudimentary nervous system, the signals of which presumably travel through the protein at the core of each fibre. Generally the sponges add organic materials to their glass fibres for added strength and flexibility, and sodium ions for increased light transmission capabilities (something unfeasible in high-temperature, traditional, molten glass-making). The living tissue they do possess is syncytial (no cell walls) and areas of tissue can be connected by distinctively hollow cell-plugs.
On a lighter note...
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