Everyone knows the value of the annual rings of a tree. According to him, not only can determine the age of the tree, but also to reconstruct the climate of the past. How can recover paleoclimatic conditions in the areas of water basins?
On the scales of fish, often found in ancient marine and lake sediments, there are rings like tree rings. Call them sclerites. This ossified portions of scales, which are not closed or serried ridges on the outside of her bed. They appear as a result of changes in food fish.
Gap distance between sclerites depends on the environmental conditions and the genetic code that is embedded in the body. In good times, growth accelerated in the unfavorable period of sharply slowing. This forms the annual ring. In the tropics, slower growth may be due to poor nutrition during the dry season and the water level dropped. Sclerites value reflects the frequency monsoon climate. In addition, some events in the life of the fish cause the appearance of additional rings: in the second year — the juvenile, after him-spawning.
Thus, the width of the gaps mezhskleritnyh affected by ambient temperature, and their number depends on the food. And skleritogrammy so individual that they can be used to determine which body of water born fish, important information about the age of the fish populations and the ecological environment.
The scientists studied the fish scales from sediments of an ancient sea that existed in the current Crimean mountains. The age of the layers containing the object of study is defined by the residue of plants and animals. From the width of the gap between the sclerites established long-term adverse period, and by definition picture on scales — general temperature changes during the life of the fish. The obtained data are compared with reconstructed paleoclimatic conditions for flora. Coordination of the results makes it possible to speak of a new method of determining the climate of ancient times, very promising for areas where no other preserved remnants of flora and fauna.
Category: Flora and Fauna