Williamia radiata nutata is a subspecies of small sea snail or saltwater limpet with a lung, a marine pulmonate gastropod mollusc in the family Siphonariidae, the marine pulmonate limpets.

References

Radiata is a taxonomic rank that has been used to classify radially symmetric animals. The term Radiata has united several different groupings of animals, some of which do not form a monophyletic group under current views of animal phylogeny. Because of this and problems of homoplasy associated with using body symmetry as a phylogenetic character, the term is used mostly in a historical context.

In the early 19th century, Georges Cuvier united ctenophores and cnidarians in the Radiata.Thomas Cavalier-Smith, in 1983, redefined Radiata as a subkingdom consisting of Myxozoa, Placozoa, Cnidaria and Ctenophora.Lynn Margulis and K. V. Schwartz later redefined Radiata in their Five Kingdom classification, this time including only Cnidaria and Ctenophora.

Although radial symmetry is usually given as a defining characteristic in animals that have been classified in this group, there are clear exceptions and qualifications. Echinoderms, for example, exhibit unmistaken bilateral symmetry as larvae. Ctenophores exhibit biradial or rotational symmetry, defined by tentacular and pharyngeal axes, on which two anal canals are located in two diametrically opposed quadrants. Some species within the cnidarian class Anthozoa are bilaterally symmetric (For example, Nematostella vectensis). It has been suggested that bilateral symmetry may have evolved before the split between Cnidaria and Bilateria, and that the radially symmetrical cnidarians have secondarily evolved radial symmetry, meaning the bilaterality in cnidarian species like N. vectensis has a primary origin.

Medicago is a genus of flowering plants, commonly known as medick or burclover, in the legume family. It contains at least 87 species and is distributed mainly around the Mediterranean basin. The best-known member of the genus is alfalfa (M. sativa), an important forage crop, and the genus name is based on the Latin name for that plant, medica, from Greek: μηδική (πόα) median (grass). Most members of the genus are low, creeping herbs, resembling clover, but with burs (hence the common name). However, alfalfa grows to a height of 1 meter, and tree medick (M. arborea) is a shrub. Members of the genus are known to produce bioactive compounds such as medicarpin (a flavonoid) and medicagenic acid (a triterpenoid saponin).Chromosome numbers in Medicago range from 2n = 14 to 48.

The species Medicago truncatula is a model legume due to its relatively small stature, small genome (450–500 Mbp), short generation time (about 3 months), and ability to reproduce both by outcrossing and selfing.

Cisco Systems is an American computer networking company that made its first commercial acquisition in 1993, which was followed by a series of further acquisitions.

History

Founded in 1984, Cisco did not acquire a company during the first seven years of its existence; but, on September 24, 1993, Cisco acquired Crescendo Communications, a LAN switching company. Following the first Cisco takeover purchase, acquisitions have constituted 50 percent of the company's business activity.

The company's largest acquisition as of April 2008 is the purchase of Scientific-Atlanta—a manufacturer of cable television, telecommunications and broadband equipment—for US$6.9 billion. The purchase represented the interest that Cisco had in Internet television, as spending on switches and routers decreased, and expanded the corporation's consumer product base after its prior acquisition of Linksys Inc., a producer of wireless networking products for homes and small businesses. Cisco chief executive officer (CEO) at the time, John Chambers, described it as a "medium-sized" purchase, but the acquisition was the largest since Cisco paid US$7.29 billion for Cerent Corporation in 1999. The deal was announced in November 2005 and was finalized in early 2006.