A sponge's body plan has adapted to filter small food particles from passing water, allowing them to reside in most habitats, including polar shelves and underwater caverns that often contain very few nutrients.
Like other animals, sponges were also found to grow extremely slowly in cold waters such as those in Antarctica. Age estimates based on growth rates of a glass sponge (Scolymastra joubini) in the Ross hong kong email list Sea were between 15,000 and 23,000 years, meaning the specimen appears to be the longest-lived animal on Earth so far recorded. Sponges are often studied by scientists to find clues about the earliest life forms on Earth with more than one cell.
Sponges are hermaphrodites and are capable of reproducing both sexually and asexually. Most sponges generally reproduce by sexual reproduction, where sperm cells (spermatocytes) develop from choanocytes (neck cells) and eggs develop from oocytes. When environmental conditions are favourable, spermatocytes are ejected in outflow streams and the eggs, once fertilised inside the sponge in some sponges, develop into flagellated larvae that swim like plankton until they find a suitable place to settle and develop into adults. Asexual reproduction occurs when favorable environmental conditions deteriorate and includes either regeneration (regeneration from fragments), budding (clusters of cells differentiate into small sponges which are then released externally or expelled through the central canal (oscula)), or the formation of gemmules ("survival pods" of unspecialized cells that remain dormant until conditions improve and then form entirely new sponges or recolonize the skeletons of their parents).
