نتایج جستجو برای: guppy
تعداد نتایج: 615 فیلتر نتایج به سال:
Cryptic species complexes are common among parasites, which tend to have large populations and are subject to rapid evolution. Such complexes may arise through host-parasite co-evolution and/or host switching. For parasites that reproduce directly on their host, there might be increased opportunities for sympatric speciation, either by exploiting different hosts or different micro-habitats with...
Males are typically the sicker sex. Data from multiple taxa indicate that they are more likely to be infected with parasites, and are less "tolerant," or less able to mitigate the fitness costs of a given infection, than females. One cost of infection for many animals is an increased probability of being captured by a predator. A clear, hitherto untested, prediction is therefore that this paras...
زنده زایی روش بسیار موفق تولید مثلی است که در طی زمان تکامل یافته و تنوع بسیاری در گروه های جانوری دارد. تخمک رسیده ماهیان استخوانی توسط یک غشای فاقد سلولی که زونا ردیاتا نامیده می شود ، احاطه می گردد. زوناردیاتا در اکثر ماهیان استخوانی زنده زا به دو بخش تقسیم می شود : زونا ردیاتای داخلی و خارجی. در پژوهش حاضر ساختار zona radiata (zr) در تخمک ماهی (poecilia reticulata) guppy درمراحل مختلف رسی...
This study aims to determine the level of addition bean sprout flour in feed as vitamin E help reproductive system rearing guppy fish (Poecilia reticulate). The design used was a Completely Randomized Design (CRD) with 4 treatments 3 replications, each treatment was: A. Without Sprout Flour 0% (SF 0%), B 2% 2.0%), C 4% 4.0%), D 6% 6,0%). this were female measuring 0,38 – 0,51 gram. Growth gonad...
Frequency-dependent predation has been proposed as a general mechanism driving the phenotypic assortment of social groups via the 'oddity effect', which occurs when the presence of odd individuals in a group allows a predator to fixate on a single prey item, increasing the predator's attack-to-kill ratio. However, the generality of the oddity effect has been debated and, previously, there has n...
BACKGROUND Evidence on the effectiveness of low-cost, sustainable, biological vector-control tools for the Aedes mosquitoes is limited. Therefore, the purpose of this trial is to estimate the impact of guppy fish (guppies), in combination with the use of the larvicide pyriproxyfen (Sumilarv® 2MR), and Communication for Behavioral Impact (COMBI) activities to reduce entomological indices in Camb...
The evolution of exaggerated sexual ornamentation is classically thought to proceed as a compromise between opposing vectors of sexual and natural selection. In colour-based ornamentation, as exhibited by guppies (Poecilia reticulata), heightened trait expression may be beneficial in promoting attractiveness, but costly in terms of predation. Opportunities to reconcile this compromise will exis...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید