Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Mexican Biodiversity “There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved.” Charles Darwin Home > Species > Concepts > The extended family > Plants > Ginkos and Canutillos > Ginkos Ginko (Ginkophyta) What is it? How are they? Ginkgo (Division: Ginkophyta) or Gín an is a unique tree on the planet: it has no living relatives. In China, it is known as the “silver fruit” or “white fruit”. It Also has the names; “virgin’s hair”, “tree of forty golden crowns,” and “silver apricot”. The German scientist Engelbert Kaemper (16511716) discovered it in Japan in 1691. The ginko is a tree of up to 35 meters in height, with one or several trunks and deciduous leaves. They are easily distinguished by their fan-shaped leaves of 5 to 8 cm with dichotomous venation. It is a dioecious species, i.e. there are male and female individuals. They can live for more than 2,500 years. How Many? How do they live? One single species, the Ginkgo tree (Ginkgo biloba), which is considered a living fossil as its only known relatives are from the Permian period 270 million years ago. Male individuals produce pollen in small cones, while females individuals have ovules in the leaf buds. It is native to China’s forests at altitudes of up to 1,100 m. The only wild populations are found in the broadleaf forests of Mount Xitianmu in the Tian Mu Shan Reserve in the northwest of Zhejiang Province in eastern China. In ancient times however, it had a wide distribution on the planet. The light green leaves turn yellow in autumn before falling. Where does it live? For thousands of years it has been used as an ornamental tree, and has been widely planted as an urban tree in many cities such as Amsterdam, Osaka, and Washington D.C., as it has a strong resistance to pollution and disease: several ginkgos even survived the atomic bomb of Hiroshima . However, in many places only male individuals are planted, since the female produces a very strong rancid butter-like odor. Despite undergoing nearly 200 years of cultivation in North America, it has never become naturalized. In Mexico City there are some Ginkgos in the nurseries of Parque Viveros, Coyoacan, in the Parque la Bombilla and in the Bosque de Chapultepec. In common with the cycads, ferns, mosses and algae, fertilization is carried out by mobile flagellated sperm cells. Following wind-pollination, the eggs develop into yellow-brown seeds of 1.5 to 2 cm which are dispersed by birds and mammals. How do we use them? The therapeutic properties of Ginkgo are known and used in traditional Chinese medicine. The leaves contain metabolites known as flavonoids that increase blood circulation. Recently it has been commercialized worldwide, although some of its supposed properties have been questioned. In China the seeds are eaten and are considered to have positive health properties and also to act as an aphrodisiac. However, it can also become toxic. Ginkgo is considered a threatened species by the IUCN. The preference for male trees is putting its genetic diversity at risk. URL: http://www.biodiversidad.gob.mx/v_ingles/species/gran_familia/plantas/ginkos/ginko_ingles.html Contact: [email protected] | México 2009