The collembola mystery
Some people think that a sense of humour is not an obligatory feature of a good lecturer. Sometimes it is said to be unnecessary as a lecture must be serious and it goes without saying that bursts of laughter mustn’t be provoked by a teacher. But being a lecturer of the Arctic Floating University is something special because except for excellent knowledge of the subject, three more things are necessary here: first of all, it is the connection with the region (if we don’t have a chance to see, to touch or to feel the lecture subject during landings, it is treated by the consciousness as something unnecessary and forgotten); secondly, material must be delivered in portions (as a long epic story turns into something boring very quickly, at least because of the tossing, as the concentration is easily lost); and finally, it is sense of humour which is presented in the lecture not by means of single jokes, but characterizes a lecture itself (because it is hard for a person to control the situation in the Arctic, especially on board the vessel, we subconsciously feel scared, and a smile can be very useful for fighting this fear).
All expedition members knew that there was a scientist on board who had dedicated his life to the study of so-called snow flea. Soon everybody knew exactly who he was. But he is very modest and didn’t want to force his report. But today, on July 15, it finally happened due to the numerous requests of the expedition members and a direct order of the expedition head.
Anatoly Babenko, the leading research fellow of the Institute of Ecological and Evolutionary Problems named after Severtsev, Russian Academy of Sciences, Moscow started his presentation with the words: “I am a bad lecturer”. And during next 40 minutes the audience was attentively following the stories about collembola and when the report was over, the common room burst with applause. It is clear why this lecture was such a success. It is closely connected with the Arctic (Babenko collected the major part of his samples at the Novaya Zemlya and Franz Josef Land). The story itself wasn’t too epic or too complicated, though there is a lot of information on this topic. And, of course, there was humour which is already connected with the fact that the person has dedicated his whole life to the study of such small creatures.
To tell the truth, the snow flea is an everyday title, though it was mentioned even in the Aristotle time. Scientifically these creatures are called springtails, or collembola in Latin. There is a special spring on the fourth segment of their abdomen which allows a creature about 1 mm long to jump at a distance of 50 cm. It can land on any body part, so to turn around they use a special ventral tube which bleeds sticky substance (this feature gave them their Latin name because “collembola” means “bleeding glue”).
The springtails evolved from living on the surface (where they had long legs and cornicles) to living in the soil where some species lack either a spring or eyes. Earlier they were defined as a primitive insect order (they never had wings in comparison with fleas). Now they form a separate hexapod class.
Springtails like living in the Arctic. In the tropics the amount of insects is usually 30-40 times higher than the amount of springtails, but at high latitudes the numbers are almost the same because insects feel much worse in such conditions than springtails. Babenko studies the zonality of these creatures in the Arctic, and one of his tasks is to specify the fauna of Franz Josef Land. Besides, springtails were studied in Franz Josef Land only by Frederic Jackson’s expedition in the end of the XIX century and by Babenko about 30 years ago.
There are very few specialists in this sphere in the world. To tell the truth, only one – Arne Fjellberg from Norway. He is considered to be the leading collembola systematist and has been unemployed for more than 40 years. However, he travels around the world, takes part in the expeditions and scientific conferences, publishes monumental books and has a wife and two children.
— So, together since the middle of 1970s we have described about 160 new species of springtails, — says Babenko.— But I am afraid it is hard to find some more.
— Why are you so interested in Franz Josef Land?
— First of all, it is an unexplored area. Secondly, my boss studies mites, which are even more numerous in the soil than springtails. So she asked me to bring her some samples from Franz Josef Land.
There are more than 400 springtails species in the Arctic. At least 10 of them have never been found anywhere but in the Arctic. Some springtails have a well-developed breathing system, whereas others breathe through their skin. Moreover, springtails have developed unique mechanisms of cold tolerance, as hypothermia is typical for them in winters. It is very important that they manage to winter at any stage of their life cycles.
There are different cold tolerance mechanisms. Some accumulate during autumn special substances which do not let blood plasm freeze even at the temperature of – 35 degrees. Another mechanism presupposes freezing and fluctuation without tissue crystallization. It is quite widespread among insects. Both mechanisms are well-known. And during the study of springtails it was figured out that the temperature of –5-8 degrees means hypothermia for them. That is why they manage to survive during the Arctic winter. Besides, this species lives on the coast, where winters are even more severe. It turned out that after contact with ice, springtails lose almost all metabolic water, in other words, dries up. And then fills up with water again. Such mechanism is quite wide-spread among insects, including earthworms, but it was discovered in the Arctic, due to springtails!