Variant forms in -y for short, common adjectives ( vasty, hugy) helped poets keep step with classical feet when the grammatically empty but metrically useful -e dropped off such words in late Middle English. with other adjectives (for example crispy). Originally added to nouns in Old English it was used from 13c. Konrad Lipkowski, Institute for Ecology, Evolution and Diversity, Faculty of Biosciences, Riedberg Campus, Tel.Adjective suffix, "full of or characterized by," from Old English -ig, from Proto-Germanic *-iga- (source also of Dutch, Danish, German -ig, Gothic -egs), from PIE -(i)ko-, adjectival suffix, cognate with elements in Greek -ikos, Latin -icus (see -ic). The picture shows an amplectant pair belonging to the species Gammarus sp. Biological Journal of the Linnéan Society, Īn image may be downloaded at: Caption: The male amphipod (above) latches onto the smaller female (below) for up to several days and defends her against rivals. Population density affects male mate choosiness and morphology in the mate-guarding amphipod Gammarus roeselii (Crustacea: Amphipoda). Publication: Lipkowski K, Plath M, Klaus S, Sommer-Trembo C. “The population density has enormous influence on whether the male can afford to take a closer look at his mate," concludes Konrad Lipkowski. The amphipods, which are only millimetres-long, are therefore definitely choosy, with the degree of choosiness depending on the population density in their natural environments. “If, after separation, we returned the female the male itself had selected, the male accepted it just as quickly as the males from the other population accepted a new female." “Often, an amplectant pair didn't even come about," Carolin Sommer reports. The males from the population consisting of many individuals spent a significantly longer period searching through their small test basin for an alternative (hopefully better) female, before accepting the female selected by the researchers. As expected, they were not particularly choosy, since they seldom encountered females in their natural environment and therefore had to seize the opportunity immediately. The males from the populations with a very low density grasped the female within a short period. In the next step, the amplectant pairs were carefully separated from one another, and each male was offered another (morphologically similar) female, one they had not previously selected of their own accord. During this time, pairs formed, with the males firmly grasping the female and not letting her go before fertilization (amplectant pair). They collected test animals from two neighbouring areas and let them acclimate for a few days in large aquariums. In their study, Carolin Sommer-Trembo, Konrad Lipkowski and their two colleagues compare the behaviour of Gammarus males from two populations with very different densities. Scientists at Goethe University have now investigated under which circumstances males are prepared to revise their decision. This behaviour requires a lot of time and energy, so that the males make their choice with care. ![]() Amphipods of the species Gammarus roeselii guard their chosen mates, often carrying them with them for days and defending them against potential rivals.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |