It\u2019s mid-February, we celebrate the Valentine\u2019s Day, and in the morning you can hear the birds singing. The morning bird sounds prove that the spring is near. This is how birds mark their territories and begin to look for a partner and suitable location for building their nests.<\/p>\n
Spring doesn\u2019t always mark the beginning of the animal mating season. It is actually the other way round with aphids, which are the subject of research conducted by Prof. \u0141ukasz Depa. Females and males begin their mating rituals in the early autumn, more less at the turn of September and October. However, anyone who has dealt with aphids in their garden at least once knows that these hemiptera don\u2019t waste time in the spring or summer either. This is the period of intense asexual reproduction, without the males involved.<\/p>\n
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The world of aphids is dominated by females which breed by parthenogenesis. This means that their offsprings develop in ovaries without sperm, so with no male involved. It happens mainly in the summer, when the population of a particular species is quickly increasing. As a result, females give birth to subsequent generations of other females.<\/p>\n
Fortunately, it turns out that the male is still useful in this case (laughter<\/em>). The life cycle of aphids also includes the sexual reproduction phase. It provides these animals with genetic diversity, which, simply speaking, is the basis for survival of the species in the ever-changing environment. This increases the likelihood that certain percentage of population will survive in the most extreme environmental conditions. Therefore, aphids \u201ctake care\u201d of spreading fast in the spring and summer, whereas in the autumn, in a way, they \u201cseek for\u201d genetic diversity.<\/p>\n The life cycle of aphids is fascinating. In the winter their eggs are hidden well in the nooks of the host plant. Interestingly, only females hatch from the winter eggs. They give birth to further generations of females, some of which are winged. These insects may relocate to other green areas, where they will bear subsequent generations of both wingless and winged females in the late spring. Thanks to this, the area which they cover increases, and this process goes on throughout the summer.<\/p>\n In the autumn, females which give birth to offsprings of both genders, i.e. males and oviparous females, appear in the population. Therefore, sexual reproduction may occur at the turn of September and October. Eggs formed in this way are laid again in the nooks of the plant where they will overwinter. Thus, we go back to the beginning and the whole cycle repeats.<\/p>\n Zachowania samic i samc\u00f3w w okresie jesiennym nie zosta\u0142y do ko\u0144ca zbadane. Wiemy jednak, \u017ce nawet mszyce w tym kr\u00f3tkim czasie, gdy dochodzi do zap\u0142odnienia p\u0142ciowego, maj\u0105 swoje rytua\u0142y. Interesuj\u0105ce mo\u017ce by\u0107 na przyk\u0142ad zachowanie samc\u00f3w z gatunku Cinara cuneomaculata<\/em>, kt\u00f3re po kopulacji pozostawiaj\u0105 na grzbiecie samicy \u015blady wydzieliny. Jest to jasny sygna\u0142 dla innych samc\u00f3w: tu wszystko si\u0119 ju\u017c wydarzy\u0142o, trzeba szuka\u0107 gdzie indziej.<\/p>\n There are obviously also cases when males are fighting for a female, it\u2019s a normal phenomenon. An interesting fact is the reverse, ventro-ventral copulation, which we managed to observe in Stomaphis graffii<\/em>species. I was surprised when I saw it for the first time. What we usually observe is ventro-dorsal contact. Two different ways of copulation in hemiptera? It\u2019s unusual in the world of insects.<\/p>\n \n<\/div>\r\n <\/div>\r\n <\/div>[\/vc_column][vc_column width=”1\/3″]\r\n ![\"Grafika](\"https:\/\/us.edu.pl\/wp-content\/uploads\/image\/mszyce.png\")
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