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Dagmar I. Werner Esmeralda M. Baker Elizabeth del C. Gonzalez Ines R. Sosa 《Behavioral ecology and sociobiology》1987,21(2):83-89
Summary The research addressed two questions: (1) doIguana iguana hatchlings recognize their kin, and (2) what are the recognition mechanisms? Eggs were collected from wild and captive-raised
females and hatched in semi-natural incubators. In the first experiment we used eggs from two females. One of the clutches
was subdivided to be placed in different incubators. Immediately after emergence one of these hatchling groups was introduced
into a 10 m x 10 m enclosure. At the same time we introduced hatchlings from another female. The remaining hatchling group
was kept separate for 3 weeks and was then introduced into the same cage. Unrelated hatchlings separated from each other.
Related but separated hatchlings grouped according to introduction date. In the second experiment we maintained eight kin
groups in individual cages and two hatchlings per kin group in an additonal cage. Hatchlings from the mixed group showed no
preference for their kin before physical contact with pure kin groups had occurred. After physical contact hatchling recognized
their kin by feces smell. Body odor is likely to be also involved. 相似文献
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Soil contaminations with the explosive 2,4,6-TNT are a major problem at many sites of former ammuniton plants in Germany. But only little is known about its environmental or metabolic fate in soil or plants. A field study was conducted on a former ammunition plant in Stadtallendorf/Hessen. Three areas with different TNT concentrations were planted with 8 different crops. After harvest plants were analyzed for TNT, ADNTs and DNTs. Soil contamination decreased in the rhizosphere compared to unplanted areas and there was a transfer of TNT from soil to the plants. Accumulation in plants was dependent on soil contamination and also specific for different plant parts or plant species. The contamination spectrum of TNT and derivatives was different in soil or plant tissue, respectively. After acid hydrolysis of bean roots, 2,6-DNT and 2,4-DNT could be identified in the extract. 相似文献