What are ecdysozoa?

EcDysozoa is a suggested super group group of eight animal phyla (out of approximately 37) -Arthropoda, onychophora, Tardigrad, Kinorhyncha, Priapulid, Loricifer, Nematic and Nematicfa. It is a controversial group, but a large genetic study in nature in 2008, "wide phylogenomic sampling improves the distinction of the animal tree of life", strongly supported Ecdysoa as a natural category. The group was originally designed as a result of genetic studies using 18s ribosomal RNA genes in 1997.

The primary characteristic of ECDYZOA sharing is melting the three -layer cuticle in a process called ecdysis (where the group gets its name). Another shared feature is the absence of locomotor algae in reproductive cells - sperm is amoeboid. EcDysozoa embryo is not subject to spiral cleavage, while other protrosts of the embryo yes. EcDysozoa is all the schedules, one of the two main groups of animals, the other is deuterostomes.

EcDysozoa is proposed superPhylum in bilaterals, unlimited sub -regnum (subkingdom) in animals in general. His largest group is the arthropods, which include all insects, crustaceans and arachnids and is estimated to include a total of 5-8 million species, most of the whole animal life. EcDysozoa is the largest and most prolific organisms on the planet and their combined biomass exceeds the biomass of all seven billion people.

EcDysozoa includes what was some of the earliest forms of life to develop hard shells such as arthropod trilobites, the emergence of the beginning of the Cambrian period, 542 million years ago, and the first forms of life to embark on the ground. The earliest fossil of Land Animal, Pneumodesm Newmani, 1 cm Millipede, is a member of EcDysozoa. It is likely that nematodes that cover the ocean's abysmal plains and are the swollen multicellular forms of life on Earth were actually the first on Earth, but not fossilized well.

Ironically that the cuticle of Nematod has different chemical compositions than all other ecdysozoa, so their group membership is also the most suspicious. One microscopic member of EcDysozoa, Tardigrads, is remarkable in that he is able to withstand extreme temperatures and radiation that would kill a human hundreds of times. They are the only animal that could survive the strictness of the universe for any significant time.