Eesti Looduse fotovõistlus
2012/8



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   Eesti Looduse
   fotovõistlus 2012




   AIANDUS.EE

Eesti Loodus
summary EL 2012/8

The Baltic Germans were eager researchers of mammoths
Erki Tammiksaar looks back at the research history of mammoths found from the permafrost areas of the Russian Empire. European scientists became interested in mammoths and the permafrost areas of Siberia since the beginning of the 19th century. However, these early scientists did not associate permafrost and the fact why mammoth corpses had been preserved. Karl Ernst von Baer was one of the first scientists to explain permafrost. His works were carried on by Alexander Theodor von Middendorff, who tried to associate a mammoth corpse found in 1799 with the theory of Ice Age in Siberia. While the early scientists believed that mammoths had originated from southern areas, it eventually became quite clear that it was not the truth. By the end of the 19th century it was believed that mammoths were trapped in certain territories by the ice and disappeared slowly.

Estonia may have been the last refuge of the Late Ice Age mammoths of Europe
Lembi Lõugas complements the articles about mammoths with description of Estonian data. There are about 30 findings of mammoth remains, mostly grinder teeth and pieces of fangs. Unfortunately, most of these findings have disappeared, and only some descriptions have been preserved. Three findings from around the Baltic Sea, including one from Puurmani, Estonia, indicate that these belonged to the last mammoth populations of Europe, as these are the youngest recorded findings.

Nowadays mammoth finds
Erki Tammiksaar gives an overview of mammoth fang trade: the sites of Siberia are still controlled by the Russians. The indigenous people of the Russian North, the Evenks and Evens, are allowed to collect and sell the mammoth fangs, as it is almost the only income for the local people of the Yakutia. Every year, some 40–45 tons of mammoth fangs are traded, according to the official data. The best quality fangs may cost up to $ 200/kg.

Ice Age is back at Äksi
Toomas Jüriado recommends the recently opened Äksi Ice Age Center: it provides a good overview of the development of Estonian nature and settlement history after the last ice age.

Bird flight
Tuul Sepp states that despite of numerous researches the phenomenon of bird flight is still difficult to explain. The ability to fly varies a lot among bird species. The flight style depends upon the shape of wings. Long feathers, such as eagles have, are helpful in maneuvering. However, for fast flights and quick maneuvers short feathers are a better choice. Any kind of flying needs a lot of energy and therefore all flying birds have very fast metabolism. The article describes a number of interesting examples of different flying methods of different bird species, and takes a short look at development history: how dinosaurs might have evolved into birds.

Refreshment from the seeds of the cola tree
Urmas Kokassaar describes the nuts with special stimulatory effect caused by alkaloids, especially caffeines. The cola tree seeds are used in a number of nature products. The two Cola species used for chewing originate from West-Africa and were used for centuries to fend off sleepiness and feeling of hunger on long journeys. In nowadays modern world the cola seeds are mostly used in two ways: as an additive in foods and drinks, and in medicine.

Interview: The man who took bird rings named „ESTONIA MATSALU“ into use
Toomas Kukk has interviewed Taivo Kastepõld, an ornithologist and the laureate of Eerik Kumari prize.

Estonian Nature enquires
Annely Reinloo gives an overview of restoring semi-natural habitats.
Hanno Zingel looks at the perspectives brought by validating the nature conservation development plan.

The secret life of horsehair worms
Mati Martin takes a peek into the family life of harmless, but scary-looking water worms. These thin, but very long worms (reaching about 70–80 cm in Estonia) live in waterbodies and pose no harm for humans. The life cycle of horse worms is complicated and not much studied, and the different species of the family are difficult to differentiate.

Hiking trail: The military past of the Mustoja landscape protection area
Toomas Valk takes the reader to the former practice field of the horse troops in the far south-east corner of Estonia, Setomaa, where unique landscape and military heritage create good preconditions for exciting trips. The article gives an overview of the history of the area, including the possible origin of the exciting local place names. In recent years, three hiking trails have been founded in the area. The most recent one is the 43 km-long biking trail which largely runs on the former shooting grounds of Pechory. The article follows the course of the trail and is supplemented with a detailed map of the trail and several photographs of the area.

Only the strongest can survive in sand II
Siim Sepp continues introducing the sands of the world. This time, mostly different oxides are elaborated on. Oxide minerals are very wide-spread in sands, as they are resistant to chemical weathering. The best-known of such minerals are corundum, rutile, ilmenite and cassiterite. The article also looks at several silicate minerals, which are quite rare in sands, such as olivines, quartz, epidotes and pyroxenes. All the minerals have a unique shape and colour, which are well depicted in the numerous close-up photographs supplementing the article.




28/11/2012
26/11/2012
05/10/2012
09/07/2012
26/06/2012
26/06/2012
22/05/2012

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