sea squirts

meet your distant cousin  the see squirt. Never mind it looks like a rubbery bag with two spouts. It  belongs to the same group or phylum that you do the Chordata. Most animals is chordata  are vertebrates with backbones. Sea  squirts  however  are invertebrates like octopus or clams- no backbones!So how did they end up in chordata. The answer found in the young or larval form of the sea squirts.A sea  squid lava body contains a stiff rod called a notochord . It also has a nerve cord. These body part are like  the ones found in the bodies of vertebrate as they grow and change inside an egg like bird or inside the mother  body like a human. In  a vertebrate howerve these structures  disappear into the backbones and spinal cord. It  a sea squirt  they disappear. When  a sea squirt larva is ready to become  an adult  is body absorbs its tail notochord  and cord. This  happens very quickly in just a few hours -s even just a few minutes or seconds - depending on the  species.Most species of sea squirts attach themselves to rocks and other hard surfaces and then stay there the rest of their lives. Some  species mesh together to form colonies. A sea squirt  eats by pulling water into its baggy body through one of its tow siphons. The water flows through a basketlike  filter  sticky with mucus which traps food particles. The waste is squirted out from other siphon.Sea squirts belong to a group of animals  known as tunicates. This word refers to the tough covering or tunic on sea squirts body.  Imgine  for a dive and meeting a glowing blue -green tube longer than a pickup truck snaking through the  water! You've just encountered a pyosme a name that means fire body. A pyrosome is a colony of tunicates. It made up of hundred or thousand of tiny squitlike individual called zooids contained in a  jellylike tunic. They re all copies or cones of each other because the  whole colony starts with one zooid that reproduced itself.Each zoos takes in water  filters out food and than ejects the water into the hollow center of the tube.Their combined squirting moves the colony moves the colony through the water. a pyroxene drifts in the waters off pico island in the azores. The tow siphons of a sea squirt are easily seen on these blue squirts.