Ribbon Worms

Ribbon Worms, also known as Cerebratulus lacteus, is a phylum of invertebrate animals. This phylum is also know as Nemertea. Ribbon worms can be produced sexually or asexually and they can grow from 5 meters to 30 meters in length. Ribbon worms feed all their life and reproduce. Ribbon worms have a distinguishable proboscis that allows them to catch their prey.

Most ribbon worms are found on the seafloor while some live in different waters such as brackish water and fresh water. Ribbon worms are long, thin, unsegmented animals. They have a closed circulatory and digestive system. They have a mouth and an anus like most worms, and most ribbon worms are predatory, while some are scavengers and herbivores. They have a brain with several nerve cords, and they perform respiration by diffusion.

The earliest record of a ribbon worm was recorded in 1555 by Olaus Magnus, and he reported a long, greyish-blue marine worm which was believed to be Lineus longissimus. Also, there is a nemertean fossil called Archisymplectes. Perhaps our ribbon worms today evolved from those early nemerteans. Ribbon worms used to be called degenerate flatworms, but now they are recognized as a seperate phylum.

Tube Worms

So I was watching the discovery channel and it was a show about the deep sea. It got to a section about tube worms and it said they were one of the oldest living marine animals on earth. Tube worms can live for a period of time. Tube worms can grow up to 2.4 meters in length. It takes about 175 to 200 years for them to grow at least 2 meters. Some tube worms live for much much longer than that. Tube worm colonies can live for about 1000 years but an individual can't. Tube worms can tolerate extremely high temperatures and sulfur levels. They are found near black smokers and that is how they feed, but they have no digestive tract. Tube worms have a symbiotic relationship with bacteria that perform chemosynthesis. These bacteria live within specific organs of the tube worm and they make up a good amount of the tube worm's weight. The tube worm's red plume- organ used to exchange compounds with the environment- provides the bacteria with nutrients, and the bacteria perform chemosynthesis and allow the tube worms to feed.