Relics - are organisms, preserved in the world in certain areas since ancient times, in spite of the changing conditions of existence.They are the remnants of ancestral groups, widespread in the past geological epochs.The word "relic" comes from the Latin reliquus, which means "stay."
relic plants and animals are of great scientific value.They are the carriers of information and can tell a lot about the natural environment of bygone eras.Let's get acquainted with plant organisms classified as a relic.
Geographic relic plants
to geographical relict species of plants are preserved in a particular region as a remnant of the past geological epochs in which living conditions were very different from today's.So, to the Neogene (Tertiary) relics include tree species of trees (chestnut, zelkova and others), a number of evergreen shrubs (Goryanka Colchis, boxwood, ruscus aculeatus, rhododendron ponticum, etc..) And herbaceous plants that grow in Colchis.This is a fairly heat-loving species of relict plants, so they are kept in areas with warm climates.
Examples glacial relicts are Potentilla marsh, which grows in the Caucasus, and dwarf birch, which is preserved in central Europe.
phylogenetic relicts (living fossils)
These currently existing species belong to taxa, almost completely extinct millions of years ago.Preserved they are usually due to the isolation of their range from the more progressive groups.To carry such a phylogenetic relic plants, like the ginkgo, Metasequoia, horsetail, sciadopitys, Wollemi, Liquidambar, Welwitschia.
relic Ginkgo tree is one of the oldest in the world.Studies of fossil specimens show that Ginkgo age is not less than 200 million years.They appeared at the beginning of the Late Permian, Jurassic and in the middle grows already at least 15 genera Ginkgo.
Ginkgo biloba (Ginkgo biloba) - only kind that has been preserved to this day.It is a deciduous plant belonging to gymnosperms.Its height is 40 meters.Trees are characterized by well-developed root system, resistant to adverse weather conditions, in particular to the strong winds.There are instances that reached the age of 2.5 thousand. Years.
because in addition to ginkgo gymnosperms belong to pine and spruce, previously considered our plant also belong to the pine, although it is very different from them.However, to date, there are suggestions that the ancestors are ancient Ginkgo seed ferns.
used to see these so-called living fossils could only in China and Japan.But today, the plant is cultivated in parks and botanical gardens in North America, Europe and the subtropical zone.
Metasequoia
belongs to the genus of coniferous trees cypress family.Currently, there is only a surviving relic - gliptostrobovidnaya Metasequoia (Metasequoia glyptostroboides).Widespread plants of this species were in the forests in the Northern Hemisphere.They began to die out because of climate change and competition with deciduous species.Live specimens of this tree were found in 1943.Prior to this Metasequoia found only in the form of fossils and was considered extinct.
Today the relic plants are preserved in the wild only in the provinces of Sichuan and Hubei (central China) and are included in the International Red Book, because they are on the verge of extinction.
Through visual appeal Metasequoia is grown in gardens and parks of Central Asia, Ukraine, Crimea, the Caucasus, as well as in Canada, the United States and in several European countries.
Liquidambar Liquidambar (Liquidambar) is a genus of flowering plants in the family Aptingievye, including five species.Widespread data relic plants were in the Tertiary period.The cause of their extinction in Europe was a massive ice during the Ice Age.Climate change and contributed to the extinction of species in North America and the Far East.
Today Liquidambar common in North America, Europe and Asia.
is a fairly large deciduous trees that grow up to 25-40 meters, with palmate-lobed leaves and small flowers, gathered in globular inflorescence.The fruit has a kind of woody capsule, which is located inside the set seed.
horsetail
These relics - a kind of vascular plants, preserved in large quantities and counts today about 30 species.All varieties are now growing perennial grasses.The height can grow to several meters.The largest species is the giant horsetail (Equisetum giganteum).When a trunk diameter not exceeding 0.03 m, it can reach a maximum height of 12 meters.Growing giant horsetail in Chile, Mexico, Peru and Cuba.There grows the most powerful kind - Schaffner horsetail (Equisetum schaffneri).At a height of 2 m diameter is 10 cm.
horsetail stems characterized by high stiffness, which is explained by the presence of silica.Also, plants have strongly developed rhizomes with adventitious roots at the nodes through which are very resistant to various adverse factors and can survive even wildfire.Horsetails are common on most continents, only exceptions are Australia and Antarctica.
Wollemi Pine
relict tree represented by a single species - the Wollemi noble (Wollémia nóbilis).He is one of the oldest plants.It grows even in the Jurassic period.The plant was thought to be extinct for a long time.However, in 1994, the Wollemi was discovered by a member of the National Park of Australia David Noble, in whose honor and was named views (nobilis - "noble").It was found almost entire relict grove.Age of the oldest trees found was supposedly over 1,000 years.
Wollemi is quite a tall tree.Thus, it can reach 35-40 meters.Foliage plants are completely identical leaves Agatis Jurassic, there are about 150 million years ago and is supposed fossil ancestors Wollemi from the late Jurassic period.
sciadopitys
There is only one form - sciadopitys whorled (Sciadopitys verticillata).In the past geological epochs this kind of tree was a huge spread.This is evidenced by the fact that their remains were found in the Cretaceous in Japan, Greenland, Norway, Yakutia, in the Urals.
Currently in nature sciadopitys grows only on some islands in Japan, where he remained at the height of 500-1000 m above sea level in the humid mountain forests, as well as on the slopes, in the remote gorges in the groves.
sciadopitys - evergreen tree has a pyramidal crown.Can grow to a height of 40 m. The trunk girth - 4 meters.It is characterized by very slow growth.The tree is often called "umbrella pine" because of the unique structure of the needles.Its flattened needle having an average length of 0.15 m to form a false whorls and spread apart sideways, as if in the umbrella spokes.
sciadopitys fruits are oval cones, which the ripening period is two years.
As long sciadopitys can grow in containers, it is often used in ornamental horticulture as indoor and greenhouse plants.As the park culture introduced in Europe from the 19th century.
Welwitschia Welwitschia amazing (Welwítschia mirábilis) - the only extant species.One of the three members of the former rather numerous class gnetalians that occur today.The name Welwitschia amazing received because of its unusual appearance.
plant like no grass or a bush or a tree.It is a thick trunk, 15-50 cm above the surface of the soil.The rest part of it is hidden under the ground.And thus leaves CMB reach 2 meters wide and 6 meters in length.The age of some specimens over 2000 years.
Welwitschia is the locus of the south-western part of Africa, namely rocky Namib Desert, located along the Atlantic coast.The plant is very rare to find more than 100 meters from the shore.This is because it is such a distance can overcome the fog that for Welwitschia is a source of life-giving water.
