Evolutionary history of plants seed model is shared by basically all gymnosperms (literally: "naked seeds"), most of which encase their seeds in a woody cone or fleshy aril (the yew, for example), but none of which fully enclose their seeds. The angiosperms ("vessel seeds") are the only group to fully enclose the seed, in a carpel. Fully enclosed seeds opened up a new pathway for plants to follow: that of seed dormancy. The embryo, completely isolated from the external atmosphere and hence protected from desiccation, could survive some years of drought before germinating. Gymnosperm seeds from the Late Carboniferous have been found to contain
Naked short selling a price rise. In 2008, the SEC banned what it called "abusive naked short selling" in the United States, as well as some other jurisdictions, as a method of driving down share prices. Failing to deliver shares is legal under certain circumstances, and naked short selling is not "per se" illegal. In the United States, naked short selling is covered by various SEC regulations which prohibit the practice. Critics, including Overstock.com's Patrick M. Byrne, have advocated for stricter regulations against naked short selling. In 2005, "Regulation SHO" was enacted; requiring that broker-dealers have grounds to believe that shares will be