Pollen are the tectum and the foot layer, which is just above the intine. The tectum and foot layer are separated by a region called the columella, which is composed of strengthening rods. The outer wall is constructed with a resistant biopolymer called sporopollenin. Pollen apertures are regions of the pollen wall that may involve exine thinning or a significant reduction in exine thickness. They allow shrinking and swelling of the grain caused by changes in moisture content. Elongated apertures or furrows in the pollen grain are called colpi (singular: colpus) or sulci (singular: sulcus). Apertures that are more circular are
Development of Spore survive in a strange world, with elements of "Nintendogs". The mobile phone version of "Spore", called "Spore Origins", was based on the tide pool phase, in which players try to survive as a multicellular organism, with gameplay similar to "flOw". On March 6, 2008, an iPhone version was demonstrated at Apple's iPhone SDK press event, though there was no commitment to ship such a product given at that event. The iPhone-Spore demo made use of the device's touch capabilities and 3-axis accelerometer. Electronic Arts confirmed on March 31, 2008 that "Spore" would be receiving post-release expansion packs. Only one expansion