Overview
Phylum Porifera - Sponges
Te Papa holds the largest and most comprehensive collection of sponges in New Zealand (strongly complemented by that at NIWA). The collection contains more than 2600 specimen lots, as well as more than 155 name bearing types (some merotypes), including holotypes and voucher material of species
Sponges come in a wide variety of colours and forms. Most are marine, with approximately 5000 species, however, thereare around 150 freshwater species. Habitats range from the inter-tidal to depths of 6,000 metres and they are found in polar, temperate and tropical regions.
Adult sponges attach themselves to hard substrates and are most common in rocky reef areas.
Sponges have small pores in the body walls through which water is drawn, and larger openings (usually near the top of the sponge) for exhalent currents. Cells in the sponge walls filter oxygen and food (bacteria) from the water as the water is pumped through the body. Sponges use the water current and the process of diffusion to absorb oxygen from the water and to get rid of their metabolic waste products.
Sponges can reproduce asexually by a process known as "budding", whereby an out-growth or bud develops into a new sponge. They also reproduce sexually: sponges are hermaphrodite (both male and female); they are not self-fertilizing, but a population will all release eggs and sperm on a certain night (coordinated by the full moon), and a sperm will fertilse an egg in the water, producing new sponges.